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  • Organic Chemistry  (3,129)
  • Cell & Developmental Biology
  • 1965-1969  (4,048)
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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 219-221 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Diazocarbonyl Compounds, XXXI V I ). o-Quinone Diazides and o-Quinones as Dehydrobenzene InterceptorsSuitably substituted o-quinone diazides can be used to intercept arynes with simultaneous N2-elimination and formation of dibenzofuranes. o-Quinones add arynes in a Diels-Alder synthesis to form cyclic diketo compounds, which react with o-phenylenediamine to give the corresponding quinoxalines.
    Notes: Arine lassen sich mit geeignet substituierten o-Chinondiaziden unter N2-Abspaltung und Bildung von Dibenzofuranen abfangen. o-Chinone addieren nach Diels-Alder Arine zu cyclischen Diketo-Verbindungen, die mit o-Phenylendiamin zu den entsprechenden Chinoxalinen kondensieren.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 231-233 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Oxidative Degradation of 5,6-DimethylbenzimidazolePrior to carrying out tracer experiments used in the investigation of the biosynthesis of 5,6-dimethylbenzimidazole (1) methods for its degradation had to be worked out. In order to identify all C-atoms, 1 had to be degraded by two procedures: The Kuhn-Roth degradation yields acetic acid and CO2. The acetic acid undergoes Schmidt degradation thus allowing the identification of C-5, C-6, and the methyl groups of 1. - The oxidation of 1 with K2Cr2O7 yields imidazole-4,5-dicarboxylic acid (4) which after decarboxylation gives imidazole and CO2. Thus C-2, C-8, and C-9 on the one hand and C-4 and C-7 on the other hand can be identified.
    Notes: Für Tracerversuche zur Biosynthese von 5.6-Dimethyl-benzimidazol (1) wurde 1 oxydativ abgebaut. Die Identifizierung sämtlicher C-Atome gelingt nur durch Abbau nach zwei Methoden: Der Kuhn-Roth-Abbau führt zu Essigsäure und CO2. Durch anschließenden Schmidt-Abbau der Essigsäure können C-5, C-6 und die Methyl-Gruppen von 1 identifiziert werden. - Die Oxydation mit Kaliumdichromat führt zu Imidazol-dicarbonsäure-(4.5) (4), deren Decarboxylierung zu Imidazol und CO2 die Identifizierung von C-2, C-8 und C-9 bzw. C-4 und C-7 erlaubt.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 49-55 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Molecular Structure Changes in Chemical Reactions, XXI 1 ). Deamination in the Bicyclo[2.2.l]-heptane SeriesThe deamination of bornyl- and fenchylamines is studied by gas chromatography. In contrast to norbornylamines the exo and endo compounds behave differently. A Wagner-Meerwein rearrangement is the main reaction in both cases. The resulting tertiary alcohol in the fenchane series is stereochemically mixed. Ring opening is considerable with endo amines but only slight with exo amines. The results are compared with those of the solvolysis in methanol of the corresponding tosylates.
    Notes: Die Desaminierung der Bornyl- und Fenchylamine wird gaschromatographisch untersucht; die im Gegensatz zu den Norbornylaminen bestehenden Verschiedenheiten von exo- und endo- Form werden festgelegt. Die Hauptreaktion ist allerdings in beiden Fällen eine Wagner-Meerwein-Umlagerung. Der entstehende tertiäre Alkohol in der Fenchan-Reihe ist sterisch nicht einheitlich. Eine Ringspaltung tritt bei den endo-Aminen erheblich, bei den exo-Aminen minimal ein. Die Ergebnisse werden mit denen der Methanolyse der entsprechenden Tosylate verglichen.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 119-123 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Azobarbituric Acid arid Alloxan AzineAzobarbituric acid (2) is formed as a by-product of the reaction between barbituric acid and carbamoylazide (H2NCON3), the main product being 5-aminocarbonylbarbituric acid. It is easily dehydrogenated by bromine water to give alloxan azine (3) which readily undergoes disproportionation yielding 2, diazobarbituric acid (1), and alloxan (5). 2 can be prepared in good yield by coupling diazobarbituric acid with barbituric acid in alkaline medium.
    Notes: Azobarbitursäure (2) tritt als Nebenprodukt der Reaktion zwischen Barbitursäure und Carbamoylazid (H2NCON3) zu 5-Aminocarbonyl-barbitursäure auf. 2 wird durch Bromwasser zu Aloxanazin (3) oxydiert, das leicht disproportioniert, wobei 2, Diazobarbitursäure (1) und Alloxan (5) entstehen. 2 wird in guter Ausbeute durch Kupplung von Diazobarbitursäure mit Barbitursäure in alkalischem Medium dargestellt.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 139-145 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyanacetaldehyde Derivatives and Reaction ProductsThe reaction of malondialdehydedioxim (2) with aromatic diazonium salts or nitrous acid leads to derivatives 5 of cyanoacetaldehyde in a quite simple way. The hydrazones of these compounds can be converted into 1-substituted 5-aminopyrazoles 6.
    Notes: Ausgehend vom Malondialdehyddioxim (2) erschließt sich über die Umsetzung mit Aryldiazoniumsalzen oder salpetriger Säure ein einfacher Zugang zu Cyanacetaldehyd-Derivaten 5, von denen sich die Hydrazone in 1-substituierte 5-Amino-pyrazole 6 überführen lassen.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 124-138 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Triazolylbenzoic Acids and Acylaminoquinazolones from Benzoxazinones and Curbohydrazideso(4-s-Triazolyl)benzoic acids 2 can easily be prepared in good yields from so-called acylanthranils with carbohydrazides in boiling ethanol. In hot benzene, the isomeric 3-acyl-amino-4-quinazolones 1 are formed from the same components. Both reactions proceed via amidrazones 11, which are formed by the reaction of the terminal hydrazide nitrogen atom with the oxazinone nucleus at C-2. - 3,4,5-Trisubstituted s-triazoles can also be made from N-substituted imidoyl chlorides with hydrazides. - s-Triazolo[4,3-a]quinolines of the type 18c are available by intramolecular condensation of certain triazolylbenzoic acids.
    Notes: o-[s-Triazolyl-(4)]-benzoesäuren 2 können präparativ einfach aus [Acylanthranilen] und Carbonsäurehydraziden in siedendem absolutem äthanol gewonnen werden. Aus den gleichen Komponenten bilden sich in Benzol die isomeren 3-Acylamino-chinazolone-(4) 1. Beide Reaktionen verlaufen über Amidrazone 11, gebildet bei der Reaktion des endständigen Hydrazid-Stickstoffs mit dem Kohlenstoff-Atom 2 des Oxazinon-Ringes. - Eine weitere Synthese für den 3.4.5-trisubstituierten s-Triazol-Ring ist mit N-substituierten Imidchloriden 7 und Hydraziden ausführbar. Bestimmte Triazolylbenzosäuren lassen sich zu s-Triazolo[4.3-a]chinolinen vom Typ 18c kondensieren.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 198-204 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Frog Venoms.Isolation and Structure of Pumiliotoxin CPumiliotoxin C, a base of the composition C13H25N, is isolated as the crystalline hydrochloride from the skin extracts of Dendrobates pumilio, a strikingly colored Panamanian frog. Complete X-ray analysis of this new venom by the so-called symbolic addition procedure establishes the structure as 2-n-propyl-5-methyl-cis-decahydroquinoline, a type of base, though related to coniine, is here reported for the first time as a natural product. The relative configurations of the four asymmetric centers are elucidated. In addition to this venom there are the congeners pumiliotoxins A and B, as well as further homologs and analogs which have also been isolated from the related frog Dendrobates auratus, and characterized by mass spectra.
    Notes: Aus dem Hautextrakt des in Panama vorkommenden, auffallend gefärbten Froschs Dendrobates pumilio läβt sich das gut kristallisierende Hydrochlorid einer Base Pumiliotoxin C der Formel C13H25N isolieren. Durch Röntgen-Strukturanalyse dieser Base nach dem „symbolischen Additionsverfahren“ (symbolic addition procedure) läβt sich zeigen, daβ es sich um einen zum ersten Mal in der Natur beobachteten, dem Coniin weitläufig verwandten Giftstofftyp handelt, nämlich um ein 2-n-Propyl-5-methyl-cis-decahydrochinolin, dessen vier asymmetrische Zentren in ihrer relativen stereochemischen Bezeichnung aufgeklärt werden. Neben Pumiliotoxin C leiten sich auf Grund der Massenspektren die Pumiliotoxine A und B sowie noch weitere aus dem verwandten Frosch Dendrobates auratus isolierte Basen von einem ähnlichen cis-Deca- oder Octahydrochinolin-System ab.
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  • 8
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Constituents of the Horse Chestnut, VII 1). O-Isopropylidene Derivatives of Protoescigenin, Barringtogenol C,and their 21-Angelic (Tiglic) Acid and 28-Angelic (Tiglic) Acid EstersThe O-isopropylidene derivatives of protoescigenin barringtogenol C, and their 21-angelic (tiglic) acid and 28-angelic(tiglic) acid esters have been prepared by reaction with acetone/p-toluenesulfonic acid. The substances were isolated by column chromatography and their structures have been determined.
    Notes: O-Isopropyliden-Derivate von Protoäscigenin, Barringtogenol C und von deren 21- bzw. 28-Angelika(Tiglin)säureestern werden durch Umsetzung mit Aceton/p-Toluolsulfonsäure hergestellt, durch Säulenchromatographie isoliert und in ihrer Struktur bestimmt.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 729 (1969), S. 237-239 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses and Properties of Dithioamino Acid EstersFrom the previously unknown class of dithioamino acid esters three members have been synthesized: N-benzoyl dithioglycine ethyl ester, ∊-amino-dithiocaproic acid ethyl ester p-toluenesulfonate, and N-acetyl dithiophenylalanine ethyl ester. The syntheses have been carried out via the nitriles. The absorption bands of the C=S-group are at approximately 3100 Å and approximately 4500 Å (table 1). The proton magnetic resonance spectrum of the prototypic N-benzoyl dithioglycine ethyl ester (page 238) is consistent with its proposed structure.
    Notes: Aus der bisher unbekannten Gruppe der Dithioaminosäureester werden drei Vertreter dargestellt: N-Benzoyl-dithioglycinäthylester, ∊-Aminodithiocapronsäureäthylester-p-toluolsulfonat und N-Acetyl-dithiophenylalaninäthylester. Die Darstellung erfolgt über die Nitrile. Die Absorptionsbanden der C=S-Gruppe liegen bei ca. 3100 Å und ca. 4500 Å (Tab. 1). Das Protonenresonanzspektrum von N-Benzoyl-dithioglycinäthylester (S. 238) entspricht seiner Struktur.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 725 (1969), S. 238-240 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 3H-DesmethylphalloinA radioactive desmethylphalloin (2) is obtained by reduction of the CO-group of ketophalloidin (1) with 3H-containing NaBH4. It has almost the same toxicity as phalloidin (LD50=2.2 mg/kg body weight of the white mouse). As a consequence of the relatively high radioactivity (220 μCi/mg) 2 gives during storing a degradation product, which can be separated by chromatography on Sephadex G-25 or LH-20 using water as eluent, and whose UV-spectrum indicates a sulfoxide structure.
    Notes: Durch Reduktion der Ketogruppe des Ketophalloidins (1) mit 3H-haltigen NaBH4 wird ein radioaktives Desmethylphalloin (2) erhalten, das etwa dieselbe Toxizität wie Phalloidin besitzt. Infolge der hohen spezif. Aktivität (220 μCi/mg) entsteht beim Lagern aus 2 ein chromatographisch an Sephadex G-25 oder LH-20 in Wasser abtrennbares Zersetzungsprodukt, dessen UV-Absorptionskurve auf das Vorliegen einer Sulfoxid-Struktur hindeutet.
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  • 11
    Electronic Resource
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 726 (1969), S. 13-18 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phosphorus Pentafluoride and Boron Trifluoride in Liquid TrifluoromethanePhosphorus pentafluoride and boron trifluoride form conducting solutions in liquid trifluoromethane. The adducts (CH3)3N·PF5 and (CH3)3N·BF3 and also the salts [(CH3)3NH] [PF6] and [(CH3)3NH][BF4], respectively, may be obtained from these solutions by addition of trimethylamine. Complex anions containing trifluoromethyl ligands are not formed.
    Notes: Phosphor(V)-fluorid bzw. Bor(III)-fluorid zeigen in flüssigem Trifluormethan elektrisches Leitvermögen. Aus den Lösungen lassen sich mit Trimethylamin die Addukte (CH3)3N· PF5 bzw. (CH3)3N·BF3 und die Salze [(CH3)3NH][PF6] bzw. [(CH3)3NH][BF4] gewinnen. Trifluormethylhaltige Komplex-Anionen werden nicht gebildet.
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  • 12
    Electronic Resource
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 726 (1969), S. 36-41 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Carbenes Derived from Bicyclo[3.3.0]octaneBicyclo[3.3.o]octane derivatives with divalent carbon in position 2 show little tendency to undergo intramolecular insertion with formation of tricyclo[3.2.1.02,8]octane derivatives. The tosylhydrazone of 2-bicyclo[3.3.0]octanone (1) yields predominantly 2-bicyclo[3.3.0]octene (2). the tosylhydrazone 7 of 10 bicyclo[3.3.0]octene-4-one prefer intermolecular reactions 9formation of ether) and affords less than 10% fo 4-tricyclo[3.2.1.02,8] octene (8).
    Notes: Carbene der Bicyclo[33.30]octan-Reihe mit zweibindigem Kohlenstoff in 2-Stellung zeigen geringe Neigung zu intramolekularer Einschiebung unter Bildung von Tricyclo[3.2.1.02.8]-octan-Derivaten. Aus Bicyclo[3.3.0]octanon-(2)-tosylhydrazon (1) entsteht bei alkalisch thermischer Spaltung vorwiegend Bicyclo[3.3.0]octen-(2) (2). Bicyclo[3.3.0]octen-(1)-on(4) tosylhydrazon (7) weicht auf intermolekulare Reaktionen (äther-Bildung) aus und liefert maximal 10% Tricyclo[3.2.1.02.8]octen-(4) (8).
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  • 13
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 726 (1969), S. 77-80 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Preparation of AziridinesAddition of chlorine and acetonitrile to olefins yields dichloroimines 1. By methanolysis of 1, followed by acid hydrolysis, we obtained via the iminoesters 4 the β-chloroamines 5, which are easily converted into aziridines 3. It is not necessary to isolate the intermediate products.
    Notes: Eie Addition von Chlor und Acetonitril an Olefine ergibt Dichlorimine 1. Durch Methanolyse von 1 und anschließende saure Hydrolyse erhielten wir über die Iminoester 4 die β-Chloramine 5, die sich leicht in Aziridine 3 überführen lassen. Die Isolierung der Zwischenprodukte ist nicht erforderlich.
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  • 14
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 106-109 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with Quinones in situ, VII 1). Preparation of 7-Dimethylamino-2-hydroxyphenothiazin-3-one7-Dimethylamino-2-hydroxyphenothiazin-3-one (4) is obtained for the first time by using 2-amino-5-dimethylanilin-thiosulfuric acid (1) as starting material. There are two different procedures, the second procedure allows the isolation of the intermediate indophenol.
    Notes: 7-Dimethylamino-2-hydroxy-phenothiazinon-(3) (4) wird auf zwei Wegen aus 2-Amino-5-dimethyl-anilin-thioschwefelsäure (1) erstmalig dargestellt. Bei dem zweiten Reaktionsweg läßt sich die Indophenol-Zwischenstufe isolieren.
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  • 15
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 125-129 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A Novel Synthesis of AntamanidBy cyclization of the linear decapeptide phenylalanyl-phenylalanyl-prolyl -prolyl-phenyl-alanyl-phenylalanyl-valyl-prolyl-prolyl-alanine (position 5 → 4 in formula 1,) with the help of dicyclohexylcarbodiimide/N-hydroxy-succinimide (DCC/HOSu) antamanid (1,) is obtained in a 36.5% yield.
    Notes: Durch Ringschluß des linearen Decapeptids Phe-Phe-Pro-Pro-Phe-Phe-Val-Pro-Pro-Ala (Stellung 5 → 4 in Formel 1) mittels Dicyclohexylcarbodiimid/N-Hydroxy-succinimid wird das cyclische Decapeptid Antamanid in 36.5 proz. Ausbeute erhalten.
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  • 16
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Catalytic Conversion of Olefins, I If'). Synthesis of cis,trans-l.5-Cyclodecadiene and I,trans-4.9-Decatriene. Co-oligomerization of Butadiene with EthyleneButadiene and ethylene can react together in the presence of “naked nickel” or nickel ligand catalytic systems to give cis,trans-1,5-cyclodecadiene (4; in yields of up to 80%). The intermediate 1 rearranges thermally to cis-1,2-divinylcyclohexane (6). 1, trans-4.9-Decatriene (5) is formed preferentially from butadiene and ethylene at 100°. Other unsaturated systems may also be included in the co-oligomerization reaction.
    Notes: Mit Hilfe von “nacktem Nickel” bzw. von Ligand/Ni-Katalysatoren können Butadien und äthylen zum cis.trans-Cyclodecadien-(1.5) (4) zusammengelagert werden (Ausbeute bis zu 80%). 4 lagert sich thermisch in cis-1.2-Divinyl-cyclohexan (6) um. Bei 100° entsteht aus Butadien und äthylen bevorzugt Decatrien-(1.trans-4.9) (5). In die Mischoligomerisation können auch andere ungesättigte Systeme einbezogen werden.
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  • 17
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Diazocarbonyl Compounds, XXXIII1). Reaction of o-Quinone Diazides with Ethyl p-Nitrophenylacetate and p-Nitrobenzylcyanideo-Quinone diazides react with p-NO2-C6H4-Ch2-CO2C2H5 and p-NO2-C6H4-CH2-CN to 2-hydroxyphenylhydrazones of the related keto compounds (table 1). The substances 1-9 are indicators. The cyano compound 8 shows solvatochromy reaching over the whole visible spectrum. The colour of the solution is related to the ability of the solvent to solvatise protons.
    Notes: o-Chinondiazide reagieren mit p-Nitrophenyl-essigsäureäthylester sowie mit p-Nitrobenzylcyanid zu 2-Hydroxy-arylhydrazonen der entsprechenden Keto-Verbindungen (Tab. 1). Die Substanzen 1-9 sind Indikatoren. Die Cyan-Verbindung 8 zeigt eine über das ganze sichtbare Spektrum gehende Solvatochromie, wobei ein Zusammenhang zwischen der Lösungsfarbe und der Fähigkeit des Lösungsmittels, Protonen zu solvatisieren, besteht.
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  • 18
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 727 (1969), S. 228-230 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Mesomeric Kations, I. Synthesis of S-Aryl-thiuronium SaltsS-Aryl-tetramethyl-thiuronium perchlorates (3) are synthesized by reaction of tetramethylthiourea with activated aromatic halogen compounds (2) or with substituted diazonium salts. The reaction of tetramethylchloroformamidinium chloride (4) with thiophenols also gives the compounds 3 in high yields.
    Notes: Zur Synthese von S-Aryl-tetramethylthiuroniumperchloraten (3) läßt sich Tetramethylthioharnstoff mit aktivierten Halogenbenzolen (2) oder mit Diazoniumsalzen arylieren. Außerdem führt die Umsetzung von Tetramethyl-chlorformamidiniumchlorid (4) mit Thiophenolen ebenfalls glatt zu den Verbindungen 3.
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  • 19
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 728 (1969), S. 12-16 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Iodosobenzene dichloride with Symmetrical EthersIodosobenzene dichloride (1) reacts with symmetrical ethers 2 under exposure to light, yielding monochloroethers 3. The formation of 1,2-dichloroethers 9, which are formed by interaction of chlorine with ethers 2, is not observed. The reaction of 1 with 2 can be explained by means of a chain reaction of C6H5-I -Cl radicals.
    Notes: Phenyljodidchlorid (1) reagiert mit symmetrischen äthern 2 bei Lichteinwirkung zu Monochloräthern 3. Das Auftreten von 1.2-Dichloräthern 9, die bei der Einwirkung von Chlor auf äther 2 entstehen, wird nicht beobachtet. Mit einer Kettenreaktion über C6H5-J.-Cl-Radikale läßt sich die Umsetzung von 1 mit 2 zu Monochloräthern 3 erklären.
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  • 20
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    Liebigs Annalen 728 (1969), S. 36-43 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: I,2-Dithia-cyclopentenes, X V1). 3-Halogeno-I,2-dithiolium-compounds and Compounds with Positive Halogen3, 5, 9, 10 have been prepared from 3-halogeno-1,2-dithiolium-compounds and compounds with positive halogen. The 3-halogeno-5-amino-1,2-dithiolium-compound 13 does not react; that is interpreted by resonance structures of 13.
    Notes: 3-Halogen-1.2-dithiolium-Verbindungen mit Chlor oder dem Phenyl-Rest in 5-Stellung reagieren mit Substanzen, die „positives Halogen“ enthalten, unter Eliminierung von elementarem Halogen zu Verbindungen vom Typ 3, 5, 9, 10. Die 3-Halogen-5-amino-1.2-dithiolium-Verbindung 13 reagiert nicht; Mesomeriebetrachtungen erklären den Befund.
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  • 21
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    Liebigs Annalen 728 (1969), S. 64-87 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on Cyclohexenes, I. Synthesis and Reactions of 3-Amino-4-phenyl-cyclohexenes-(l), a Novel Class of AnalgesicsEthyl atropate (1a) and related alkenes (1b-e) undergo diene-(1.4)-cycloaddition reactions with the electron-rich 1-amino-butadienes-(1,3) 2a-e to give the stable, stereoisomeric 3-amino-4-phenyl-cyclohexenes-(1) 3a-i and 4a-i. The ratio of the isomers does not depend on the dielectric constant of the solvent used in case of 3r-dimethylamino-4c-ethoxycarbonyl-4t-phenyl-cyclohexene-(1) (3a) and 3r-dimethylamino-4t-ethoxycarbonyl-4c-phenyl-cyclohexene-(1) (4a). It however depends on the spatial requirements of the substituents of the alkene and diene (table 1). Structure of 3a and 4a have been established by NMR, mass and infrared spectra analysis and by degradation. - Assigned conformational preferences to 3a-i and 4a-i are confirmed by the hydrogenation rate of the cyclohexene double bond, by supra-annular effects and by the basicity constants of the hydrogenated and nonhydrogenated compounds. - All cyclohexenes 3a-i and 4a, e, g, i are active analgesics. The cyclohexanes 7-10, 17, and 22-25 have no or only weak analgesic properties.
    Notes: Atropasäureäthylester (1a) und verwandte Alkene (1b-e) gehen mit den Elektronen-reichen 1-Amino-butadienen-(1.3) 2a-e Dien-(1.4)-Cycloadditionen ein, die zu stabilen, stereoisomeren 4-Phenyl-3-amino-cyclohexenen-(1) 3a-i und 4a-i führen. Das Verhältnis der Isomeren ist beim 3r-Dimethylamino-4t(bzw. 4c)-phenyl-4c(bzw. 4t)-äthoxycarbonyl-cyclohexen-(1) (3a bzw. 4a) unabhängig von der Dielektrizitätskonstanten des bei der Addition verwendeten Lösungsmittels, jedoch abhängig von der Raumerfüllung der Liganden am En und Dien (Tab. 1). Die Struktur von 3a und 4a wird durch Massen-, NMR und IR-spetroskopische Untersuchungen sowie durch Abbau bewiesen. Mittels Konformationsbetrachtungen gewonnene Aussagen über den räumlichen Bau von 3a-i und 4a-i werden bestätigt vom Geschwindigkeitsverlauf der Hydrierung der Ring-Doppelbindung, von supra-annularen Effekten und den Basizitätskonstanten der hydrierten bzw. nicht-hydrierten Verbindungen. - Alle Cyclohexene 3a-i und 4a,e,g,i besitzen analgetische Aktivität; die Cyclohexane 7-10, 17 und 22-25 besitzen keine oder nur schwache analgetische Eigenschaften.
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  • 22
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    Liebigs Annalen 728 (1969), S. 115-143 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metal Complexes of PorphyrinsThe preparation of a series of porphyrin metal complexes is described, and the widely varying spectra of porphyrin complexes are interpreted in terms of known and newly discovered facts. The salts of ms-tetrasubstituted porphins have recently been recognized as derivatives of alloporphins (6); similarly, the porphyrins of the hemin and chlorophyll series form olivegreen or brown allo-complexes. The constitution 8 hitherto assigned to all porphin complexes actually only applies to the red-normal complexes including oxyhemoglobin. Valence-tautomeric chromophores such as 11, 15, and others are to be considered for allo-complexes including hemin.
    Notes: Die Darstellung einer Reihe von Porphyrin-Metall-Komplexen wird beschrieben. Unter Berücksichtigung von bekanntem und neuem Tatsachenmaterial wird eine Deutung der unterschiedlichen Elektronenspektren der Porphyrinkomplexe gegeben. Ausgehend von Salzen ms-tetrasubstituierter Porphine, die als Alloporphin-Derivate (6) erkannt wurden, werden olivgrüne bis braune Metallchelate von Porphyrinen der Hämin- und Chlorophyll-Reihe als Allokomplexe aufgefaßt. Die bisher den Porphyrin-Komplexen allgemein zuerteilte Konstitution 8 gilt nur für die roten Normalkomplexe, denen auch Oxyhämoglobin zuzurechnen ist. Für die Allokomplexe, zu denen Hämin gehört, werden Valenz-tautomere Chromophore wie 11, 15 und andere angenommen.
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  • 23
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    Liebigs Annalen 728 (1969), S. 184-192 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: N-Substituted Derivatives of Dehydroubietylamine and DehydroabietylguanidineThe following derivatives of dehydroabietylamine have been synthesized in order to investigate their antimicrobial activity: N-monoalkyl- and N.N-dialkyl-dehydroabietylamines; dehydroabietylguanidines, which are substituted at the N- or N′-atom by an alkyl-, substituted alkyl-, acyl-, amino- or nitro-group; dehydroabietylurea, -thiourea, salts of dehydroabietylisourea and -isothiourea, quaternary dehydroabietylammonium salts and 2-dehydroabietylamino-pyrimidine.
    Notes: Zur Untersuchung ihrer antimikrobiellen Wirkung werden aus Dehydroabietylamin dargestellt: N-Monoalkyl- und N.N-Dialkyl-dehydroabietylamine, am N- oder N'-Atom durch eine Alkyl-, substit. Alkyl-, Acyl-, Amino- oder Nitro-Gruppe substituierte Dehydroabietylguanidine, Dehydroabietylharnstoff, -thioharnstoff, Salze des Dehydroabietylisoharnstoffs und -isothioharnstoffs, quaternäre Dehydroabietylammoniumsalze und 2-Dehydroabietyl-amino-pyrimidin.
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  • 24
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    Liebigs Annalen 729 (1969), S. 1-7 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organometallic Compounds of the Groups IVa and Va, I. Alkoxytriphenylursine- and Alkoxytriphenylantimony HalidesThe reactions of tert.-butylhypohalities (2a and b) with triphenylarsine (1c) and triphenyl-antimony (1a) have been investigated an dht eproperties of the triphenyl-tert.-butoxyarsine-and - antimony halides (3a-d) formed have been examined.
    Notes: Die Umsetzung von tert.-Butylhypohalogeniten (2a und b) mit Triphenylarsin (1c) un d-stibin (1a) und die Eigenschaften der dabei entstehenden Triphenyl-tert.-butyloxy-arsen - und -antimonhalogenide (3a-d) werden untersucht.
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  • 25
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    Liebigs Annalen 729 (1969), S. 8-20 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Wagner- Meerwein Rearrangements in the Bicyclo[3.2.2rsqb;nonane Series I )Deamination of the epimeric 6-aminobicyclo[3.2.2]non-8-enes (6 and 7) and 6-aminobicyclo-[3.2.2]nonanes (8, X = NH2 and 9) mainly proceeds via a stereospecific rearrangement to yield exo-alcohols of hte bicyclo[3.3.1]nonane or bicyclo[4.2.1]nonane series with high stereospecifity. In addition, tricyclo[4.2.1.02.8]nonan-7-ol (10) was produced from the endo-amin 7. - In the presence of silver bromide 2-bromobicyclo[3.2.2]nonane (8, X = Br) rearranges to 2-bromobicyclo[3.3.1]nonane (2, Y = Br). - Both the dehydration of bicyclo[3.2.2]nonan-6-ol (1, X = OH) with phosphoric acid and the acid-catalyzed rearrangement of bicyclo-[3.2.2]non-6-ene (12) give rise to bicyclo[3.3.1]non-2-2ne (11, X = H). The reaction of 12 with an excess of monoperphthalic acid yields syn- and anti-bicyclo[3.3.1.13.9]decane (17). -The deamination of 2e-aminomethylbicyclo[3.2.1]octane (18 gives a mixture of alcohols consisting of bicyclo-[4.2.,1]nonan-3-ol (36), bicyclo[4.2.1]nonan-2-ol (3, Y = OH), bicyclo[3.3.1]nonan-2-ol (2, Y = OH), and 2a-and 2e-methylbicyclo[3.2.1]octan-2e- and 2a-ols (20 and 19).
    Notes: Die Desaminierungen der epimeren 6-Amino-bicyclo[3.2.2]nonene-(8) (6 und 7) und 6-Aminobicyclo[3.2.2]nonane (8, X = NH2, und 9) führen stereospezifisch zu exo-Alkoholen der Bicyclo[3.3.1]nonan- oder Bicyclo[4.2.1]nonan-Reihe. Das endo-Amin 7 liefert daneben Tricyclo[4.2.1.02.8]nonanol-(7) (10). - 6-Brom-bicyclo[3.2.2]nonan (8, X = Br) lagert sich in Gegenwart von AgBr in 2-Brom-bicyclo[3.3.1]nonan (2, Y = Br) um. -Die Dehydratisierung von Bicyclo[3.2.2]nonanol-(6) (1, X = OH) mit Phosphorsäure und die säurekatalysierte Umlagerung von Bicyclo[3.2.2]nonanol-(6) (1, X = OH) mit Phosphorsäure und die säurekatalysierte Umlagerung von Bicyclo[3.2.2]nonen-(6) (12) führen zu Bicyclo[3.3.1]nonen-(2) (11, X = H). - Aus 12 bilden sich mit überschüss. Monoperphthalsäure syn- und anti- Bicyclo[3.3.1]nonen-(2)-ol-(9) (14 und 15) sowie vermutlich 10-Oxatricyclo[3.3.1.13.9]decan (17). - Bei der Desaminierung des 2e-Aminomethyl-bicyclo[3.2.1]octans (18) entstehen Bicyclo[4.2.1]nonanol-(3) (36), Bicyclo[4.2.1]nonanol-(2) (3), Y = OH), Bicyclo[3.3.1]nonanol-(2) (2, Y = OH) sowie 2a und 2e-Methyl-bicycol[3.2.1]octanol-2c und 2a) (20 und 19).
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  • 26
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    Liebigs Annalen 729 (1969), S. 52-63 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of Ally1 Alcohols with Active Methine and Methylene Compoundsγ.δ-Unsaturated ketones 4 are intermediates in several syntheses of natural products. They may be obtained from allyl alcohols and β-keto esters. Novel synthetic approaches to γ.δ-unsaturated ketones 4 and the related compounds 12, 14, 16, and 18 are described (tables 7-10). The investigations lead to a new synthetic route for the preparation of the juvenile hormone (10).
    Notes: γ.δ-Ungesättigte Ketone 4, herstellbar aus Allylalkoholen und β-Ketoestern, sind Zwischenprodukte verschiedener Naturstoff-Synthesen. Es werden neue Synthesemöglichkeiten von 4 und den damit verwandten Verbindungen 12, 14, 16 und 18 (Tabb. 7 - 10) beschrieben. Die Arbeiten führen zu einem Herstellungsverfahren des Juvenilhormons (10).
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  • 27
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    Liebigs Annalen 729 (1969), S. 69-72 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Cyclopentadienones, XVII).1,4-Cycloaddition of Dibenzoyldiimide to CyclopentadienonesThe cyclopentadienones 2-7 and dibenzoyldiimide (1) give the corresponding 1,4-compounds 8-12. By heating in xylene the product 8 rearranges to the lactone 13. Reaction mechanisms are discussed.
    Notes: Die Cyclopentadienone 2-7 werden mit Dibenzoyldiimid (1) zu den entsprechenden 1.4-Addukten 8-12 umgesetzt. Erhitzen von 8 in Xylol liefert das Lacton 13. Die Reaktionsmechanismen werden diskutiert.
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  • 28
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    Liebigs Annalen 729 (1969), S. 106-118 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese of Phosphinimine CompoundsA number of new phosphinimine compounds of s-triazines is obtained by the reaction of triamino-s-triazine (9) with triphenylphosphine and halogenes (table 1) or of trichloromelamine (17, table 2) or hexachloromelamine (26, table 3) with tertiary phosphines. The components react in the absence of dehydrohalogenating compounds. Only one reaction step is necessary for the formation of the products. All these methods give pure products in good yields.
    Notes: Eine Reihe neuer Phosphinimin-Derivate von s-Triazinen (Tab. 1) wird in einer Stufe mit groβer Reinheit und hohen Ausbeuten aus Triamino-s-triazinen (9), Triphenylphosphin und Halogenen in Abwesenheit von Halogenwasserstoff bindenden Verbindungen sowie aus Trichlormelamin (17, Tab. 2) oder Hexachlormelamin (26, Tab. 3) und tertiären Phosphinen erhalten.
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  • 29
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    Liebigs Annalen 729 (1969), S. 146-151 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Synthesis of 1,2-BenzisothiazolesA new method has been found for the preparation of 1,2-benzisothiazoles (1). The compounds are formed by reaction of dihalomethyl-2,6-dihalobenzenes with elementary sulfur and ammonia in a solvent.
    Notes: Es wurde eine neue Herstellungsweise für 1.2-Benzisothiazole (1) gefunden. Die Verbindungen entstehen durch Umsetzen von 2.6-Dihalogen-benzylidenhalogeniden mit elementarem Schwefel und Ammoniak in einem Lösungsmittel.
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  • 30
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    Liebigs Annalen 729 (1969), S. 184-192 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ubiquinones and Related Compounds, XV. Photochemical Reaction of Ubiquinone-7trans-Ubiquinone-7 (1) is converted to several compounds by irradiation of its ethanolic solution with sunlight. One of them, 2a, had been reported previously by us to be an isomer in which the β,γ-double bond of 1 has migrated to the α,β-position. 2a is reinvestigated and its correct structure found to be trans-γ-ethoxy-isoubiquinone-7 (chart 1). In methanol 1 gives the γ-methoxy compund 2b in the same manner. The configurations of α,β-double bond in isoubiquinone groups, 2a, 2b, 2c, and 8 were deduced from the n.m.r. spectra of the corresponding hydroquinone diacetates 3a, 3b, 3c, 9 (figure 1). The mechanism of the photochemical reaction is discussed (chart 2).
    Notes: trans-Ubichinon-7 (1) geht in äthanol durch Sonnenbestrahlung in mehrere Substanzen über. Eine davon, 2a, wurde früher von uns als Isomeres von 1 angesehen, in welchem die β-γ-Doppelbindung in die α.β-Position verschoben ist. Die Struktur von 2a lieβ sich jetzt als trans-γ-äthoxy-isoubichinon-7 richtigstellen (Schema 1). 1 ergibt in Methanol analog das Methoxy-Derivat 2b. Die Konfiguration der α.β-Doppelbindung in der Isoubichinon-Gruppe 2a-c und 8 kann durch die NMR-Spektren ihrer Diacetylhydrochinone 3a-c und 9 festgestellt werden (Abb. 1). Der Mechanismus dieser Photoreaktion wird diskutiert (Schema 2).
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    Liebigs Annalen 729 (1969), S. 249-250 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Natural Tannins, XLIII). (-)-Chebulic Acid from AlgarobillaChebulic acid (1, R = H) is prepared by acid hydrolysis of Algarobilla extracts. It has been shown to be the optical antipode of the acid obtained from Myrobalanes.
    Notes: Aus Algarobilla-Extrakten wird durch Hydrolyse Chebulsäure (1, R = H) abgespalten, die sich als das Spiegelbild der aus Myrobalanen erhaltenen Säure erweist.
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    Liebigs Annalen 729 (1969), S. 246-248 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Enol Ethers, VIII. Reactions of Aldehydes with Electron-rich Alkenes1-Dimethylamino-1-ethoxyethylene (1) and 1,1-dipiperidinoethylene (2) react with aromatic aldehydes 3 to give cinnamamides. Coumarines are obtained on reaction with salicylic aldehydes.
    Notes: 1-Dimethylamino-1-äthoxy-äthylen (1) und 1.1-Dipiperidino-äthylen (2) reagieren mit aromatischen Aldehyden 3 zu Zimtsäureamiden. Mit Salicylaldehyden erhält man in glatter Reaktion Cumarine.
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    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions of CH-Active Compounds with Azides, XXVII ). Syntheses of a-Diazo-imines und Isomeric 1,2,3-Triazoles and Their Conversion into a-Diazo-immonium Salts1-Anilino-3-oxo-indenes 6a-f are converted into 1-oxo-3-arylimino-2-diazo-indanes 8a-c or 1-oxo-3-aryl-3H,8H-indeno [1,2-d]triazoles 9d-f by diazo group transfer with p-toluenesulfonyl azide in ethanol/potassium ethoxide. Both classes of substances add mineral acids to form 1-oxo-3-arylimmonium-2-diazo-indane-salts 10a-f. Treatment of the immonium salts with potassium hydroxide yields the α-diazo-imines 8a, b, e and f. 8c hydrolyses to give 1,3-dioxo-2-diazo-indane; 8d, which changes largely to 9d by cyclisation, is accessible by thermal ringopening of the latter. 1-Anilino-3-oxo-cyclohexenes-(1) 12a-f are transformed into 4-oxo-1-aryl-4,5,6,7-tetrahydro-benzotriazoles (14a-f) by diazo group transfer with high yields.
    Notes: 1-Anilino-3-oxo-indene 6a-f liefern bei der Diazogruppen-übertragung mit p-Toluolsulfonsäure-azid in äthanol/Kaliumäthylat 1-Oxo-3-arylimino-2-diazo-indane 8a-c bzw. 1-Oxo-3-aryl-3H.8H-indeno[1.2-d]triazole 9d-f. 8 und 9 addieren Mineralsäuren - 9 unter Ringöffnung - zu 1-Oxo-3-arylimmonium-2-diazo-indan-Salzen 10a-f. Mit Kaliumhydroxid erhält man daraus die α-Diazo-imine 8a, b, e und f. 8c hydrolysiert weiter zu 1.3-Dioxo-2-diazo-indan; 8d cyclisiert größtenteils zum Triazol 9d, ist aber durch dessen direkte thermische Isomerisierung zugänglich. 1-Anilino-3-oxo-cyclohexene-(1) 12a-f werden durch Diazogruppen-übertragung mit hohen Ausbeuten in 4-Oxo-1-aryl-4.5.6.7-tetrahydrobenzotriazole 14a-f umgewandelt.
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Absolute Configuration of Optically Active, Naturally Occurring Dihydroisocoumarins, IIIs2).Determination of the Absolute Configuration of Agrimonolide and MelleineBy degradation with ozone and performic acid (S)-3-hydroxy-adipic acid is obtained from both agrimonolide (1) and (-)-β-tetralol (4), which is characterized as di-hydrazide 3. Therefore 1 and 4 have S-configuration at position 3 and 2 respectively. The positive CD at 260 mμ of 1 and phyllodulcine (7) is a proof of configurative identity. In contrast, melleine (8) shows at 257 mμ negative CD and therefore has R-configuration.
    Notes: Durch Abbau mit Ozon und Perameisensäure wird aus Agrimonolid (1) und (-)-β-Tetralol (4) die gleiche (S)-3-Hydroxy-adipinsäure erhalten und als Dihydrazid 3 charakterisiert. Damit geht für 1 und 4 die S-Konfiguration and C-3 bzw. C-2 hervor. Der positive CD von 1 und Phyllodulcin (7) bei 260 mμ beweist deren konfigurative übereinstimmung. Da der CD des Melleins (8) - wie 7 ein Salicylsäure-Derivat - bei 257 mü negativ ist, muß hier auf R-Konfiguration am C-3 geschlossen werden.
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    Liebigs Annalen 729 (1969) 
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    Keywords: Chemistry ; Organic Chemistry
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    Topics: Chemistry and Pharmacology
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  • 36
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    Liebigs Annalen 729 (1969), S. 21-26 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Protonated Methylbenzene Tetrachloroaluminate ComplexesWell defined complexes from methyl substituted benzenes and aligated by proton magnetic resonance (figure 1, table 1). A few of these compounds can be characterized as σ-complexes. Under the conditions used σ-protonation requires a benzene ring with at least three methyl substituents and a 1,3,5-type of substitution. In all other cases complexes are formed, in which π-bonding is likely.
    Notes: Definierte Komplexe aus Methyl-substituierten Benzolen und Aluminiumchlorid/Chlorwasserstoff wurden erhalten und auf ihre NMR-Signale untersucht (Abb. 1, Tab. 1) Nur ein Teil dieser Verbindungen kann als σ-Komplex charakterisiert werden. Unter den angewandten Bedingungen ist für die σ-Protonierung Substitution mit wenigstens drei Methyl-Gruppen in 1.3.5-Stellung erforderlich. In allen anderen Fällen ist π-Komplex-Bildung wahrscheinlich.
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    Liebigs Annalen 729 (1969), S. 40-51 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Production and Reactions of N- MonoalkylamidosulfonylchloridesN-Monosubstituted amidosulfonylchlorides (1) may optimally be obtained by reaction between N-monosubstituted ammonium chlorides and sulfuryl chloride in acetonitrile. N-Monosubstituted amidosulfonylchlorides are very active intermediates, which react especially with reactive H containing compounds to give the free acids 2 (R = H), the esters or thioester 2,5, and 6, and the amides 7 and 8. The hydrogen of the amino group can also be substituted. In this way new compounds are accessible and other already known compounds can be produced more easily.
    Notes: Unter den Methoden zur Herstellung N-monosubstituierter Amidosulfonylchloride (1) erweist sich die Umsetzung von N-monosubstituierten Ammoniumchloriden mit Sulfurylchlorid in Acetonitril als am besten geeignet. N-Monosubstituierte Amidosulfonylchloride sind sehr reaktive Zwischenprodukte, die mit reaktionsfähigen, H-enthaltenden Verbindungen zu den freien Säuren 2 (R = H), den Estern bzw. Thioestern 2, 5 und 6 sowie den Amiden 7 und 8 reagieren können; außerdem besitzen sie einen leicht substituierbaren Wasserstoff an der Amino-Gruppe. Mit ihnen sind Verbindungen präparative leicht zugänglich, die bisher nicht oder nur umständlich gewonnen werden konnten.
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  • 38
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    Liebigs Annalen 729 (1969), S. 73-82 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Catalytic Hydrogenation of PurinesHydrogenation of purines over platinum or palladium occurs initially, if at all, in the 1,6 positions (e. g. 1 → 4). The 1,6-dihydropurines, which can still be acetylated in the 7 or 9 position, can be hydrogenated further to hexahydro- and perhydropurines (20 and 13, respectively).
    Notes: Purine werden an Platin oder Palladium, wenn überhaupt, zuerst in 1.6-Stellung hydriert (z. B. 1 → 4); die 1.6-Dihydro-purine, die noch in 7- bzw. 9-Stellung acetylierbar sind, können dann weiter zu Hexahydro- bzw. Perhydro-purinen (20 bzw. 13) hydriert werden.
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  • 39
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 722 (1969) 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 40
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    Weinheim : Wiley-Blackwell
    Liebigs Annalen 722 (1969), S. 29-37 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: a-Hydrazonocarboxylic Acid Azides, I. Aliphatic α-Hydrazonocarboxylic Acid AzidesThe title compounds 2, 5a-c, 6a-e are prepared by reaction of the analogous α-hydrazonocarboxylic acid hydrazides (1, 7a-c, 8a-e) with nitrous acid. Both classes form Z- and E-isomers. The α-hydrazonocarboxylic acid hydrazides (1, 8e), that are unsubstituted in the hydrazono group, prefer the Z-form, whereas those (7a-c, 8a- d), that are substituted in the hydrazono group, prefer the E-form. The Z-azides, prepared from the Z-hydrazides, are unstable and lose hydrazoic acid. The E-azides, prepared from the E-hydrazides, are stable, but change into the unstable Z-isomers on standing at room temperature when exposed to light. On boiling in toluene the E-isomers lose nitrogen to form substituted 1,2,4-triazol-5-ones (15a-c, 16a-d).
    Notes: Die Titelverbindungen 2, 5a-c, 6a-e entstehen aus den entsprechenden α-Hydrazonocarbonsäurehydraziden (1, 7a-c, 8a-e) durch Reaktion mit salpetriger Säure. Beide Substanzklassen treten in Z- und E-Form auf. Die in der Hydrazono-Gruppe unsubstituierten α-Hydrazonocarbonsäurehydrazide (1, 8e) liegen bevorzugt in der Z-Form, die entsprechend substituierten Hydrazide (7a-c, 8a-d) überwiegend in der E-Form vor. Die aus den Z-Hydraziden entstehenden Z-Azide sind instabil und spalten Stickstoffwasserstoffsäure ab. Die aus den E-Hydraziden entstehenden E-Azide sind stabil, wandeln sich jedoch bei längerem Stehenlassen und gleichzeitiger Lichteinwirkung in die instabilen Z-Azide um. Beim Kochen der E-Azide in Toluol wird Stickstoff abgespalten und es bilden sich substituierte 1.2.4-Triazolone-(5) (15a-c, 16a- d).
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  • 41
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Intramolecular Rearrangements of Bicyclo[2,2, heptanes, XI1). Rearrangement of 1- Methyl-7,2-norbornanecarbolactone in Sulfuric AcidIn the presence of concentrated sulfuric acid 1-methyl-7,2-norbornanecarbolactone (1) rearranges to 3exo-methyl- and 1-methyl-2,6-norbornanecarbolactones (2 and 5). The structure of the hitherto unknown lactone 5 is established.
    Notes: 1-Methyl-norbornan-carbolacton-(7.2) (1) lagert sich unter dem Einfluß konzentrierter Schwefelsäure in 3 exo-Methyl- und 1-Methyl-norbornan-carbolacton-(2.6) (2 und 5) um. Die Struktur des bislang unbekannten Lactons 5 wird bewiesen.
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  • 42
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    Liebigs Annalen 722 (1969), S. 232-233 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition of Dichloroketene to 2-ButyneDichloroketene generated in situ, gives with 2-butyne the 1,2-cycloaddition product 2,3-dimethyl-4,4-dichlorocyclo-2-buten-1-on (1).
    Notes: In situ erzeugtes Dichlorketen addiert sich an Butin-(2) zum 2.3-Dimethyl-4.4-dichlor-cyclobuten-(2)-on-(1) (1).
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  • 43
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Studies on the Occurence of Hydrogen Transfer, 191). Specific Reductive Cleavage of Some Acyl Groups from Nitrogen at the Mercury CathodeElectron donators in the aromatic acyl group and in the amine component shift the reduction potentials of sulfonamides and of carbonamides to more negative values, and hinder the cathodic cleavage. Electron acceptors have the opposite effect. Aromatic ligands on the nitrogen atom change the reduction potentials to more positive values. The influence of the substituents on the reduction potentials follows the Hammett relationship. - If a potential difference of at least 0.2 V exists between acyl groups (which may be in the same molecule, or in different molecules), then selective cleavage of the acyl group having the more positive potentials is possible.
    Notes: In Sulfon und Carbonamiden mit aromatischem Acyl-Rest werden die Reduktionspotentiale durch Elektronen-Donatoren im Acyl-Rest und in der Amin-Komponente zu negativeren Werten verschoben; dabei wird die kathodische Spaltung erschwert. Elektronen-Acceptoren wirken umgekehrt. Aromatische Liganden am Stickstoff verlagern das Reduktionspotential zu positiveren Werten. Die Abhängigkeit der Reduktionspotentiale vom Substituenten gehorcht der Hammett-Beziehung. - Besteht zwischen den Acylamino-Gruppen, die im gleichen Molekül oder auch in verschiedenen Molekülen gebunden sein können, ein Potentialunterschied von wenigstens 0.2 V, so ist eine selektive Abspaltung der Acyl-Gruppe mit dem positiveren Potential möglich.
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  • 44
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    Liebigs Annalen 723 (1969), S. 41-46 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tertiary and Quaternary Salts of Hexahydro-pyrimidinesThe mono- and bis-tertiary salts 7, 11, 12 may be obtained by reaction of 1.3-dialkylhexahydro-pyrimidines and hydrogen chloride in suitable solvents. - The mono-quaternary salts 8-10 are formed from 1.3-dialkyl-hexahydro-pyrimidines and alkyl halides in ether. The bis-quaternary salts 5, 6 and 13-17 result by alkylation of 1.3-dialkyl-hexahydro-pyrimidines with methyl bromide, methyl iodide or trialkyloxonium fluoroborates in polar aprotic solvents or by reaction of α-halogen amines with γ-chloropropyl amines.
    Notes: Aus 1.3-Dialkyl-hexahydro-pyrimidinen und Chlorwasserstoff sind in geeigneten Lösungsmitteln die mono-sowie bis-tertiären Salze 7, 11, 12 zu gewinnen. - Die monoquartären Salze 8-10 entstehen aus 1.3-Dialkyl-hexahydro-pyrimidinen und Alkylhalogeniden in Äther. Die bis-quartären Salze 5, 6 und 13-17 sind durch Alkylierung von 1.3-Dialkyl-hexahydropyrimidinen mit Methylbromid oder -jodid sowie Trialkyl-oxoniumfluoroboraten in polaren, aprotischen Lösungsmitteln oder durch Umsetzung α-halogenierter Amine mit γ-Chlorpropylaminen zugänglich.
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  • 45
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    Liebigs Annalen 723 (1969), S. 201-204 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Concerning the Mechanism of Catalytic Proton-Transfer by Diazomethane, IIMethyl 3-hydroxy-2-naphthoate (8) gives with 1 mole phenyl isocyanate in the presence of 1 mole deuterodiazomethane (1.6 g-atom D/mole) an adduct 9-d0 free from deuterium; the same reaction carried out with deuterated 8 and non-deuterated diazomethane gives 9-d1. These results are in accordance with a proton-transfer by proton-bridge complexes, whereas they exclude the proton-transfer by methyldiazonium cations.
    Notes: 3-Hydroxy-naphthoesäure-(2)-methylester (8) bildet mit 1 Mol. Phenylisocyanat in Gegenwart von 1 Mol. Deuterodiazomethan (1.6 g-Atom D/Mol) das D-freie Addukt 9-d0; bei der Reaktion mit deuteriertem 8 und undeuteriertem Diazomethan entsteht dagegen 9-d1. Die Befunde lassen sich durch Protonen-Übertragung über Protonbrückenkomplexe erklären und schließen die Protonen-Übertragung durch Methyldiazonium-Kationen aus.
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  • 46
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    Liebigs Annalen 724 (1969), S. 24-29 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Conjugation in Macrocyclic Bond Systems, XIII1). Further Compounds of the Hexa-m-phenylene TypeThe preparation of the sterically overcrowded hexamethyl hexa-m-phenylene 2 is reported. Spectroscopic properties (u. v., 1H-n.m.r.) and mass spectra of 2 are discussed with regard to the strong deviation from coplanarity present in this system. Synthesis and properties of 8,2′;8′,2″;8″,2-tris(dibenzothiophenylene) (10), a coplanar a coplanar derivative of 1, are reported.
    Notes: Das sterisch stark behinderte Hexamethyl-hexa-m-phenylen 2 wird hergestellt. Die spektroskopischen Eigenschaften (UV, 1H-NMR) und das Massenspektrum von 2 werden unter dem Gesichtspunkt der hier vorliegenden starken Abweichung von der Komplanarität diskutiert. Über Synthese und Eigenschaften des 8.2′;8′.2″;8″.2-Tris-dibenzothiophenylens (10), eines ebenen Derivats von 1, wird berichtet.
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  • 47
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    Liebigs Annalen 724 (1969), S. 66-70 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photochemical and Thermal 1,4-Cycloaddition of Enamides to 1,2- Dicarbonyl CompoundsThe enamides 2 and 6 can be added to benzil and o-chinones photochemically and thermally to give the 1,4-dioxen derivatives 3 and 7. The thermal addition follows a two-step mechanism, as is shown by the formation of the same 1,4-dioxen compound 7b from the addition of cis- and trans-enamide to 5.
    Notes: Die Enamide 2 und 6 addieren sich photochemisch wie thermisch an Benzil und o-Chinone zu den 1.4-Dioxen-Derivaten 3 und 7. Der Verlauf der thermischen Addition ist zweistufig, wie bei der Reaktion von cis- und trans-Enamid (6b bzw. 2b) mit 5 gezeigt wird, die zu demselben 1.4-Dioxen-Derivat 7b führt.
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  • 48
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Nitromethane Condensation with Dialdehydes, XVI1) S-Benzyl Substituted Nitrodithiols by cyclizing Bismercaptoalkylation of Nitromethane2-Nitrocyclohexanedithiols with trans-, chiro-, and cis-configuration (5-7) are formed by nitromethane-cyclization of glutaraldehyde in the presence of α-toluenethiol or by reaction of 2-nitrocyclohexane-1,3-diol (11) with α-toluenethiol, the product distribution being dependent on the reaction conditions. - Analogously, a 1,4-dinitrocyclohexanetetrathiol (15) is formed from 1,4-dinitro-1,4-dideoxy-neo-inositol (13), whereas its tetraacetate 16 gives 2-nitro-5-benzylmercaptophenol (17), as a result of aromatization followed by nucleophilic displacement of one nitro group by a mercapto moiety. - Configuration and conformation of the nitro dithiols and of the sulfones 8-10 obtained on oxidation are deduced from n.m.r. spectra.
    Notes: Nitromethan-Cyclisierung von Glutardialdehyd in Gegenwart von Benzylmercaptan oder Umsetzung von 2-Nitro-cyclohexandiol-(1.3) (11) mit Benzylmercaptan führt zu 2-Nitro-cyclohexan-dithiolen mit trans-, chiro- und cis-Konfiguration (5-7), deren Mengenverhältnis von den Reaktionsbedingungen abhängt. - Aus 1.4-Dinitro-1.4-Dinitro-1.4-didesoxy-neo-inosit (13) erhält man analog ein 1.4-Dinitro-cyclohexantetrathiol (15), aus dem Dinitrotetraacetat 16 dagegen, infolge Aromatisierung und nucleophiler Verdrängung einer Nitro- durch eine Mercapto-Gruppe, 2-Nitro-5-benzylmercapto-phenol (17). - Konfiguration und Konformation der Nitrodithiole sowie der durch Oxydation erhaltenen Sulfone 8-10 ergeben sich aus den NMR-Spektren.
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  • 49
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    Liebigs Annalen 724 (1969), S. 128-136 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation und Hydrolysis of 4- Halogenomethylen-1.3-dioxolanes4-Halogenomethylen-1,3-dioxolanes (4a-o) are obtained by base-catalyzed addition of formaldehyde to 1-halogen-1-propyn-3-ols (3). Acid hydrolysis of the dioxolane derivatives 4 yields 1-halopropan-3-ol-2-ones (5a-f, i-o), which split off hydrogen halide to give 2,3-diketones 6 and 7a-c, if the hydroxyl group is attached to a primary or secondary carbon atom.
    Notes: Durch basenkatalysierte Addition von Formaldehyd an 1-Halogen-propin-(1)-ole-(3) (3) werden 4-Halogenmethylen-1.3-dioxolane (4a-o) erhalten. Die saure Hydrolyse von 4 führt zu 1-Halogen-propanol-(3)-onen-(2) (5a-f, i-o). Soweit diese eine primäre oder sekundäre Hydroxy-Gruppe enthalten (5a-f), werden sie beim Erwärmen in die 2.3-Diketone 6 bzw. 7a-c und Halogenwasserstoff gespalten.
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  • 50
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    Liebigs Annalen 724 (1969), S. 155-158 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1-(2- Hydroxyphenyl)-3,5-diphenyl-Δ2-pyrazolines2-Hydroxyphenylhydrazine hydrochlorides 1a-g and chalcone form 1-(2-hydroxyphenyl)-3,5-diphenyl-Δ2-pyrazolines (2a-g). The isolation of chalcone 2-hydroxyphenylhydrazones 3a and 3b depends on the substituents of the compounds 1a-g. - 1,3,5-Triphenyl-Δ2-pyrazolines show fluorescence, 1-(2-hydroxyphenyl)-3,5-diphenyl-Δ2-pyrazolines do not. Acetylation of the phenyl group leads to fluorescent compounds 4a-e.
    Notes: Aus den 2-Hydroxy-phenylhydrazin-hydrochloriden 1a-g, und Benzylidenacetophenon werden 1-[2-Hydroxy-phenyl]-3.5-diphenyl-Δ2-pyrazoline (2a-g) hergestellt. In Abhängigkeit von der Substitution der Verbindungen 1a-g, können bei gleichen Reaktionsbedingungen die Benzylidenacetophenon-2-hydroxy-phenylhydrazone 3a und 3b als Zwischenstufen isoliert werden. - Im Gegensatz zu 1.3.5-Triphenyl-Δ2-pyrazolinen fluoreszieren 1-[2-Hydroxyphenyl]-3.5-diphenyl-Δ2-pyrazoline nicht. Acetylierung der Hydroxyl-Gruppe führt zu fluoreszierenden Verbindungen 4a-e.
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  • 51
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    Liebigs Annalen 724 (1969), S. 183-193 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Triterpenes, XXVII1). The Structure of Musennin and DeglucomusenninThe bark of the roots of Albizzia anthelmintica (Brongn.) contains a mixture of saponins, the main components of which, musennin and deglucomusennin, have now been isolated. The sugar chains are attached to the 3-hydroxy group of the aglycon echinocystic acid. Deglucomusennin contains three molecules of l-arabino-pyranose in an unbranched chain. They are connected in α-1,2-position. Musennin has an additional molecule of D-glucose, in β-1,3-linkage to the last molecule of l-arabinose of the chain.
    Notes: Als Hauptkomponenten des Saponingemisches der Wurzelrinde von Albizzia anthelmintica (Brongn.) werden Musennin und Desglucomusennin erkannt, in denen jeweils eine Zuckerkette an die 3-Hydroxyl-Gruppe des Aglykons Echinocystsäure gebunden ist. Desglucomusennin enthält 3 Moll. l-Arabinose in Pyranoseform, die in unverzweigter α-1.2-Verknüpfung vorliegen. Musennin besitzt zusätzlich 1 Mol. D-Glucose, die in β-1.3-Form mit der endständigen Arabinose verbunden ist.
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  • 52
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    Liebigs Annalen 725 (1969), S. 196-202 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: NMR-Spectroscopic Studies of Acyl GlycosesA NMR spectroscopical study of the p-cumaroyl-D-glucoses (1a-e), p-hydroxybenzoyl-D-glucose (2a-e), as well as of the p-cumaroyl-L-rhamnoses (3 and 4) and 5-p-cumaroyl-D-xylofuranose (5) was carried out (table 1). The configuration and conformation, and in the case of the 1-, 2-and 6-acyl-glucoses as well as of 4-p-cumaroyl-α-methyl-L-rhamnopyranoside (4) also the position of the acyl group, have been established. With the aid of synthetic sugar esters the structure of neobignonoside, neopetunoside, and negretein could be determined.
    Notes: Aus den NMR-Spektren von p-Cumaroyl- (1a-e), p-Hydroxy-benzoyl-D-glucosen (2a-e) sowie p-Cumaroyl-L-rhamnosen (3 und 4) und 5-p-Cumaroyl-D-xylofuranose (5) (Tab. 1) werden die Konformation, Konfiguration und im Falle der 1-, 2- und 6-Acylglucosen- sowie des 4-p-Cumaroyl-α-methyl-L-rhamnopyranosids (4) die Stellung des jeweiligen Acyl-Restes ermittelt. Mit Hilfe der synthetischen Zuckerester konnte die Struktur von Neobignonosid, Neopetunosid und Negretein geklärt werden.
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  • 53
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    Liebigs Annalen 722 (1969), S. 80-97 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Oxidation Products of Thioamides, XX1). Thiourea S-dioxidesThe thiourea S-dioxides 8, 15, and 16 are prepared by oxidation of N-mono- and N.N′-disubstituted thioureas with hydrogen peroxide. Treatment of N.N′-disubstituted thiourea S-dioxides with acids affords formamidines. When N.N′-dineopentylthiourea is oxidized only N.N′-dineopentylformamidine (19) can be isolated. The properties and reactions of the thiourea S-dioxides are compared with those of pyridinesulfinic acids.
    Notes: Bei der Oxydation N-mono- und N.N′-disubstituierter Thioharnstoffe mit H2O2 lassen sich die Thioharnstoff-S-dioxide 8, 15 und 16 isolieren. Durch Behandlung mit Säuren entstehen aus N.N′-disubstituierten Thioharnstoff-S-dioxiden Amidine; bei der Oxydation des N.N′-Di-neopentyl-thioharnstoffs wird einzig N.N′-Di-neopentyl-formamidin (19) erhalten. Eigenschaften und Reaktionen der Thioharnstoff-S-dioxide werden mit denen der Pyridinsulfinsäuren verglichen.
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  • 54
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    Liebigs Annalen 722 (1969), S. 132-141 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cycloaddition Reactions with α,β-Diheterosubstituted Olefins, I. Reactions with Sulfonyl IsocyanatesThe reaction of sulfonyl isocyanates with α,β-dialkoxy substituted olefins yields N-sulfonyl-3,4-dialkoxy-2-azetidinon compounds 3 as main products and N-sulfonylcarboxylamide compounds 4. Kinetic studies on the formation of β-lactams 3 are reported and the reactions of these compounds with methanol are described. The formation of β-lactams from α,β-sulfur and nitrogen substituted olefins can be detected by i.r.spectroscopy.
    Notes: Sulfonylisocyanate reagieren mit α.β-disauerstoffsubstituierten Olefinen unter 1.2-Addition zu 1-Sulfonyl-3.4-dialkoxy-azetidinon-(2)-Verbindungen 3. Daneben bilden sich durch Substitution α.β-ungesättigte N-Sulfonyl-carbonsäureamid-Verbindungen 4. Mit Schwefel-und Stickstoff-substituierten Olefinen wird eine Azetidinon-Bildung IR-spektroskopisch nachgewiesen. Reaktionsweisen sowie kinetische Untersuchungen zur Bildung der β-Lactam-Derivate 3 werden beschrieben.
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  • 55
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    Keywords: Chemistry ; Organic Chemistry
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    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Organophosphorus Compounds, XXIII1). A New Synthesis of Tetrazoles and Iminonitriles from N- Substituted IminophosphoranesA generally applicable synthesis of 1-R1-5-R2-substituted tetrazoles by reaction of the corresponding triphenyliminophosphoranes (C6H5)P=NR1 with acid chlorides R2COCl and NaN3 is reported. The same phosphoranes react with acyl cyanides R2COCN to form the iminonitriles R2C(CN)=NR1.
    Notes: Es wird über eine allgemein anwendbare Synthese von 1-R1-5-R2-substituierten Tetrazolen durch Umsetzung von Triphenyliminophosphoranen (C6H5)3P=NR1 (R1=Alkyl, Aryl) mit Säurechloriden R2COCl (R2=Alkyl, Alkenyl) und NaN3 berichtet. Triphenyliminophosphorane lassen sich mit Säurecyaniden R2COCN zu Iminonitrilen R2C(CN)=NR1 umsetzen.
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  • 56
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    Liebigs Annalen 725 (1969), S. 73-86 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ketene Derivatives, XVI1). Electrophilic Substitution of Simple Ketene S,N-AcetalsSimple ketene S,N-acetals [R-CH=C(SCH3)NR′ 2; R=Horalkyl] react with electrophiles such as acid chlorides, activated vinyl chlorides, ketene mercaptals, ethoxymethylene sulfonic acid amides, dinitrofluorobenzene, trichloro-s-triazine and o-nitrobenzenesulfenyl chloride to give β-substituted ketene S,N-acetals. In some cases products of secondary reactions are isolated; acid chlorides, for instance, sometimes give substituted β-acyloxyacrylic acid thioamides.
    Notes: Einfache Keten-S.N-acetale [R-CH=C(SCH3)NR′2; R=H oder Alkyl] reagieren mit Elektrophilen - z. B. mit Säurechloriden (zu 4), aktivierten Vinylchloriden (zu 12), Ketenmercaptalen (zu 14), Äthoxymethylensulfonamiden (zu 22, 23), Dinitrofluorbenzol (zu 19), Cyanurchlorid (zu 18) und o-Nitro-benzolsulfensäurechlorid (zu 20, 21) - zu β-substituierten Keten-S.N-acetalen. In einigen Fällen isoliert man Produkte von Folgereaktionen; mit Säurechloriden erhält man z. T. substituierte β-Acyloxy-acrylsäurethioamide (z. B. 8).
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  • 57
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Fragmentation Reactions of Carbonyl Compounds with Electronegative β-Substituents, XV1). On the Reaction of Electronegatively β-Substituted Pivalic Acid EstersReaction of triiodo- (2) and tritosyloxy pivalic acid ester 3a, with sodium ethanolate affords 3-ethoxy-2-ethoxymethyl-1-propene (5) and diethyl carbonate (6) by a fragmentation reaction; on the other hand yields the tribromo pivalic acid ester 1b by neopentyl substitution 7a and b. Substitution of the monosubstituted pivalic acid esters 4a-d leads to the formation of 9, by products being formed at the same time. - Reaction of ethyl tosyloxypivalate (4b) with lithium organic compounds gives tetrasubstituted oxetanes 14.
    Notes: Trijod- (2) und Tritosyloxy-pivalinsäureester 3a liefern mit Na-äthylat 3-Äthoxy-2-äthoxymethyl-propen-(1) (5) und Kohlensäurediäthylester (6). Der Tribrom-pivalinsäureester 1b ergibt durch Neopentyl-Substitution 7a und b. Die monosubstituierten Pivalinsäureester 4a-d werden zu Methoxy-pivalinsäure-methylester (9) substituiert, wobei Nebenprodukte entstehen. - Umsetzung von Tosyloxy-privalinsäure-äthylester (4b) mit Lithiumorganylen ergibt die tetrasubstituierten Oxetane 14.
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  • 58
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    Liebigs Annalen 725 (1969), S. 154-166 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of Analogs of Dehydroabietylamine and Dehydroabietylguanidine by Total SynthesisAnalogs of racemic dehydroabietylamine and homodehydroabietylamine have been synthesized. The isopropyl group is replaced by hydrogen, or by a methyl or methoxy group. The guanidinium salts are prepared from the corresponding amines. Further variations include the additional introduction of a hydroxy group and substitution of the amino or guanidinium group by a quaternary ammonium or isothiouronium group.
    Notes: Es werden Analoge 2 des racemischen Dehydroabietylamins und Homodehydroabietylamins dargestellt. Dabei wird die Isopropyl-Gruppe durch Wasserstoff, eine Methyl- oder eine Methoxy-Gruppe ersetzt. Aus den Aminen werden die entsprechenden Guanidinium-Salze dargestellt. Weitere Variationen erstrecken sich auf die zusätzliche Einführung einer Hydroxy-Gruppe und Ersatz der Amino- bzw. Guanidinium-Gruppe durch eine quartäre Ammonium-oder Isothiuronium-Gruppe.
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  • 59
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Diazocarbonyl Compounds, XXXII1). Synthesis of 2-Carboxy-5-hydroxytryptamine and Pyridazine Derivatives. Japp-Klingemann-Synthesis with p-Hydroxy-phenyl-diazonium Salts or p-Chinon-diazides, respectivelyp-Hydroxybenzenediazoniumchloride (1) and 2,6-dichloro-1,4-benzoquinone-4-diazide (2) react with 3-ethoxycarbonyl-2-piperidone (3) and with ethyl 2-acetyl-4-cyanobutyrate (10) (Japp-Klingemann synthesis) to give 4-hydroxyphenylhydrazones 6, 7 nad 11, 12 respectively. The hydrazones 6 and 7 are converted into the 5-hydroxyindole dervatives 8 and 9 (E. Fischer indole synthesis), while the hydrazone 12 is cyclized to the tetrahydropyridazine derivatives 13 and 14.
    Notes: p-Hydroxy-benzoldiaziniumchlorid (1) und 2.6-Dichlor-benzochinon-(1.4)-diazid-(4) (2) werden mit 3-Äthoxycarbonyl-piperidon-(2) (3) und mit 2-Acetyl-4-cyan-buttersäureäthylester (10) nach Japp und Klingemann zu den 4-Hydroxy-phenylhydrazonen 6 und 7 bzw. 11 und 12 umgesetzt. Die Hydrazone 6 und 7 lassen sich nach E. Fischer in die 5-Hydroxy-indol-Derivate 8 und 9 überführen, während das Hydrazon 12 zu den Tetrahydropyridazin Derivaten 13 und 14 cyclisiert.
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  • 60
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    Liebigs Annalen 726 (1969), S. 125-135 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Triterpenes XXVIII1). The Saponins of Spinach (Spinacia oleracea L.)Two saponins, spinasaponin A and B, have been isolated from the roots of spinach. The structures are elucidated by acid and enzymatic hydrolysis and by methylation, fission of the resulting methyl derivatives, and identification of the methyl sugars. Accordingly, spinasaponin A is 3O-[β-D-Glucopyranosyl(1 → 3)-β-D-glucuronopyranosyl]-3β-hydroxy-Δ12-oleanen-28-acid (1a), whereas B is the corresponding derivative 2a of hederagenin.
    Notes: Aus den Wurzeln des Spinats werden zwei Saponine, Spinasaponin A und B, isoliert, deren Struktur durch saure und enzymatische Hydrolyse sowie durch Methylierung, Spaltung der Methyl-Derivate und Identifizierung der methylierten Zucker ermittelt wird. Spinasaponin A ist demnach eine 3O-[β-D-Glucopyranosyl(1 → 3)-β-D-glucuronopyranosyl-(1)]-3β-hydroxy-Δ12-oleanen-28-säure (1a), während B das entsprechende Hederagenin-Derivat 2a ist.
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  • 61
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of 6α-Fluoro-11β, 21 -dihydroxy-l6α-methyl-l,4-pregnadiene-3,20-dione (Fluocortolone) via Substrate-Structure- Directed Specific 11β- Hydroxylation by Curvularia lunataThe formation of the by-products 14 and 13, with 9α- and 14α-hydroxy groups, in the 11β-hydroxylation of 6α-fluoro-21-hydroxy-16α-methyl-4-pregnene-3,20-dione (9b) with Curvularia lunata is inhibited by using a similar substrate with 5α-bromo-substituent by sterical shielding of the α-side. A subsequent route for the synthesis of 6α-fluoro-11β,21-dihydroxy-16α-methyl-1,4-pregnadiene-3,20-dione (15) is described.
    Notes: Die bei der 11β-Hydroxylierung von 6α-Fluor-21-hydroxy-16α-methyl-4-pregnen-3.20-dion (9b) mit Curvularia lunata entstehenden Nebenprodukte 14 und 13 mit 9α- und 14α-Hydroxy-Funktion treten bei Einsatz der 5α-Brom-substituierten Vorstufe 5 durch sterische Abschirmung der α-Seite nicht auf. Der weitere Synthesegang zu 6α-Fluor-11β.21-dihydroxy-16α-methyl-1.4-pregnadien-3.20-dion (15, Fluocortolon) wird beschrieben.
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  • 62
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    Liebigs Annalen 726 (1969), S. 216-218 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses and Properties of the Nine Isomeric Tolyl ToluatesThe title compounds 5-7 (a-c) are prepared and analyzed for their chemical and spectroscopical properties.
    Notes: Die Titelverbindungen 5-7 (a-c) werden hergestellt und ihre chemischen und spektroskopischen Eigenschaften untersucht.
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    Liebigs Annalen 727 (1969), S. 22-34 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Thioamides with Sulfenyl ChloridesSulfenyl chlorides react with secondary thioamides to give iminomethyl disulfides 2. The sulfur atom is attacked by the sulfenyl chloride, even when the thioamide system is substituted by electron-withdrawing groups. Asymmetric iminomethyl disulfides obtained from the reaction of primary thioamides and sulfenyl chlorides decompose very easily, and in general they have been isolated as salts. In only one case has a neutral iminomethyl disulfide (23) been isolated. Thiobenzamide condenses with chlorocarbonyl sulfur chloride (21) to give 5-phenyl-1,2,4-dithiazol-3-one (28), whereas condensation with phenylimino-chloromethane sulfenyl chloride (20) leads to the corresponding dithiazole derivative 25, but only in small amounts.
    Notes: Durch Umsetzung von sekundären Thioamiden mit Sulfenylchloriden entstehen Iminomethyldisulfide 2. Der elektrophile Angriff des Sulfenylchlorids erfolgt auch dann am Thion-Schwefel, wenn das Thioamid-System elektronenziehende Substituenten trägt. Asymmetrische Iminomethyldisulfide aus primären Thioamiden und Sulfenylchloriden sind besonders leicht zersetzlich und nur als Salze isoliert worden. Nur in einem speziellen Fall wird ein neutrales Iminomethyldisulfid (23) aus einem primären Thioamid erhalten. Thiobenzamid reagiert mit Chlorcabonylschwefelchlorid (21) unter Ringschluß zu 5-Phenyl-1.2.4-dithiazolon-(3) (28). Bei Umsetzung mit Phenylimino-chlormethansulfenylchlorid (20) weicht die Reaktion aus, und das entsprechende Dithiazol-Derivat 25 wird nur in geringem Maße gebildet.
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    Liebigs Annalen 727 (1969), S. 61-70 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Structure of Thioamides and their Derivatives, Vl 1). Magnetic Anisotropy of the Thio-amide GroupModels of the magnetic anisotropy of the thioformamide and the thioacetamide system are developed with the aid of sterically fixed 1-thioacyl piperidines. In this way the different assignment of the signals of the cis- and trans-N-methyl groups in dimethylthioacetamide and dimethylthioformamide (2a) can be explained. The steric effects of the acid residue on the shielding conditions are discussed on the basis of the n.m.r. spectra of 1-thioisobutyryl- and 1-thiopivalyl-4-methylpiperidine (1c and d). In 1d and in N.N-dimethylthiopivalinamide (2d) rotation around the C-N bond is fast at room temperature. The 2-methyl group in 1-thioacetyl-2-methylpiperidine (1f) is axial.
    Notes: Mit Hilfe von sterisch fixierten 1-Thioacyl-piperidinen werden Modelle für die magnetische Anisotropie-Wirkung des Thioformamid- und Thioacetamid-Systems entwickelt, die die unterschiedliche Zuordnung der Signale der cis- und trans-N-Methyl-Gruppe beim Dimethylthioacetamid und Dimethylthioformamid (2a) erklären. Anhand der NMR-Spektren von 1-Thioisobutyryl- und 1-Thiopivalyl-4-methyl-piperidin (1c und d) wird der sterische Einfluß des Säurerestes auf die Abschirmverhältnisse diskutiert. 1d sowie das N.N-Dimethyl-thiopivalinsäureamid (2d) zeigen bei Raumtemperatur schnelle Rotation um die C-N-Bindung. - Die 2-Methyl-Gruppe des 1-Thioacetyl-2-methyl-piperidins (1f) ist axial angeordnet.
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Cytodifferentiation during spermiogenesis in Hydra littoralis was studied at the fine structural level. Concentration of nuclear material as well as specific orientation of granular and filamentous nuclear elements are apparent in two regions of the early spermatid: where the nuclear envelope is in contact with mitochondrial membranes at one pole of the cell and at an opposite region where the nucleus is closely apposed to the plasma membrane. Ultimately the mass of condensed nuclear material becomes concentrated at the mitochondrial pole of the cell. Additional electron-dense material is extruded from the nucleus into a large vacuole which is in continuity with the nuclear membrane as well as associated with Golgi lamellae and vesicles. Eventually all residual cytoplasm is sloughed, leaving the nucleus, mitochondria, and flagellum. These observations are suggestive of nucleocytoplasmic interactions during development, especially influences of mitochondria and plasma membranes on chromatin condensation.
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  • 66
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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    Topics: Biology , Medicine
    Notes: Structural and functional changes have been correlated during metamorphic degeneration of a single muscle fiber, the plantar retractor of G. mellonella, its axon, and their junctions to determine which features persist as long as muscle contractility. Changes commence simultaneously in muscle and nerve near cuticular attachments, and spread towards the center. Alterations associated with the muscle, including appearance of collapsed tracheoles and mitochondria with dense bodies, begin late in the last larval instar. Within 12 hours after pupal ecdysis some tracheolar withdrawal occurs, sarcoplasmic reticulum becomes reduced, and many mitochondria have dense bodies, dense membranes, or are enlarged. By 17-19 hours primary myofilaments and striations begin to disappear, microtubules and autophagic vacuole-like bodies appear, and phagocytes invade the muscle. It remains partially contractile upon electrically stimulating its nerve, the ventral nerve, until these changes spread throughout the fiber.Neuromuscular junction changes, including appearance of dense mitochondria and isolation bodies, begin late in the last larval instar. Junctions become fewer, and none remain in those muscle areas where tracheoles, sarcoplasmic reticulum, and primary myofilaments have disappeared.Preliminary studies on nerve discharge activity to the muscle suggest that nerve silence occurs at approximately the time when the muscle loses all contractility. In some axons isolation bodies appear and neurotubules are lost, other axons remain unchanged, and new ones develop later in the pupal state. Phagocytes invade the neural lamella and it disappears in the late pupa, but it reappears in the adult.The adult ventral nerve has over three times more axons and a thinner layer of glial cells than the larval nerve.
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    Journal of Morphology 127 (1969), S. 163-175 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A fine structural study of the ventricular muscle of Venus mercenaria has revealed that it is an invertebrate smooth muscle. In the relaxed state induced by acetylcholine, both thick (350 Å) and thin (80 Å) myofilaments are observed. These are loosely distributed in bundles in the periphery of the mononucleated myocytes. The central core of the cell contains an ovoid nucleus, α-glycogen rosettes, round mitochondria and numerous smooth surfaced vesicles of the endoplasmic reticulum. After exposure to serotonin, all myofilaments are compacted in the peripheral cytoplasm and become oriented parallel to the longitudinal cellular axis. This produces contraction bands visible in phase contrast microscopy. Because these myofilaments attach to the cell membrane at sites of attachment plaques, contraction of the cell results in the serial evagination or blebbing of the cell surface. The above features are clearly demonstrable in this invertebrate smooth muscle and strongly suggest a sliding filament model as the contractile mechanism in this tissue. Moreover, the cell surface is thought to play an active and major role in that process.
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    Journal of Morphology 127 (1969), S. 233-257 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: There are eight retinula cells in the ommatidium of the compound eye of the toadbug (Gelastocoris oculatus), two of which are central in position. Along the axial sides of the six peripheral retinula cells expand six cytoplasmic processes from the apical crystalline cone cells. These processes, which contain longitudinally-oriented microtubules, are associated with all eight retinula cells by means of desmosomal junctions. In addition to providing structural support, the possibility is set forth that the interconnecting cone processes might also serve to functionally integrate the retinula cells of an ommatidium. The eight retinula cells possess microvillus surfaces, which are especially prominent in the six peripheral cells, where they extend into the lumen of the ommatidium. There is evidence of pinocytotic activity at the bases of microvilli. Multivesicular bodies are present in the cytoplasm of retinula cells, and the means by which these bodies might be elaborated are discussed.
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    Journal of Morphology 128 (1969), S. 369-385 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The fine structure of the thyroid of the newt, Notophthalmus viridescens, was studied with the electron microscope. Specimens were injected I.P. with 30 μc of I131 and sample thryoids were examined at 12 hour intervals thereafter. The ultrastructure of the normal thyroid gland is described, and compared with that of the irradiated glands. The first visible ultrastructural change observed after injection of the radioiodin was a striking alteration of nuclear morphology. This effect was followed by an increase in the frequency of whorled lamellar structures, a decrease in the number of microvilli, and degeneration of the Golgi apparatus and endoplasmic reticulum. Further effects observed included an increase in the number of large cytoplasmic granules and a decrease in the number of smaller ones, the presence of autophagic vacuoles, and finally, an increase in the number of degenerated mitochondria.
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    Journal of Morphology 128 (1969), S. 309-363 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The hands of the Hominoidea evidence four adaptive modes which distinguish the lesse apes (Hylobatidae), the orangutan (Pongo), the African apes (Pan), and man (Homo) from one another. The hands of the apes consist of compromises between manipulatory and locomotor functions because selection has operated for precision of grip as well as for special locomotor mechanisms. The human hand is almost totally devoted to manipulation. The hands of gibbons, orangutans and the African apes differ in many features that may be correlated with locomotion. The gibbons and siamang are specially adapted for ricochetal arm-swinging. The great apes possess morphological adaptations for arboreal foraging and climbing distinct from those of the hylobatids. In addition, the African apes have become secondarily adapted for terrestrial quadrupedal locomotion. Many features that distinguish the hands of chimpanzees and gorillas may be associated with the development of efficient knuckele-walking propulsive and support mechanisms.
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    Journal of Morphology 128 (1969), S. 465-501 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The mechanisms of development of posterior levels of neural tubes of chick embryos were analyzed by study of serial cross-sections of a continuous series of normal embryos between 40 to 72 hours of incubation. Two extirpation experiments were performed in ovo on other embryos of the same stages. Descriptive studies revealed the presence of an overlap zone in which two types of neural tube formation occurred. Open neural tube formation (by fusion of neural folds) occurred dorsally in this region; closed neural tube formation (by canalization of solid medullary cord tissue) occurred ventrally. Extirpation of the posterior end of the neural plate produced defects within the lumbosacral region, indicating that the posterior neural plate participates in the formation of the lumbosacrum, and that the overlap zone is therefore in the lumbosacral region. Extirpation of the prospective neural tissue in the anterior end of the tail bud indicated that only the most posterior levels of the neural tube originate exclusively by cavitation of the tail bud. In both extirpation experiments a neural tube formed independently within the tail bud tissue, indicating that formation of the neural tube in this region is not dependent upon direct continuity with neural tissue anteriorly.
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    Journal of Morphology 128 (1969), S. 443-463 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The campaniform sensilla on halteres of Drosophila were studied by electron microscopy in order to establish the relationships of functional elements in the sensory system. The surface of the sensillum consists of an oval cuticular cap membrane which may contain resilin, the rubberlike protein. A border of denser cuticle rings the cap membrane, and extending down around the neural process is a third type of cuticle filled with a fourth light fibrous type. The four cuticular components form a system for displacement of the neural process. The neural process is differentiated into a terminal fan-shaped structure projecting from a bulbous dilatation which tapers to a neck region ending proximally with two basal bodies. The neural process is packed with microtubules. Surrounding the dendrite is an inner enveloping cell, attached to the basal body region by septate desmosomes and by desmosomes to which microtubules of the enveloping cell are applied. An outer enveloping cell surrounds the inner one. The tip of the neural process is covered with a dense secretion which is tightly bound to the cap membrane. The dense secretion is surrounded by an extracellular fluid which might be compressed hydraulically by the cuticular system. The stimulus of cuticular distortion could thus be transmitted to the neural process which may be displaced between its fixed ends.
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  • 73
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: In order to obtain more direct evidence for the occurrence of myoblast fusion in the developing amphibian embryo, the following transplantations were performed in vitro. The nuclei of early embryos. Ambystoma tigrinum and A. maculatum, were labeled with tritiated thymidine. Portions of prospective somite areas from these labeled donors were grafted homoplastically and orthotopically into unlabeled hosts of the same, or nearly the same, stage. The stages employed were: neurula, early tail bud, and late tail bud. Hosts were raised until they had developed into more advanced larval forms, fixed, sectioned, and prepared for radioautographic processing according to the customary procedures.The histological preparations contained varying numbers of multinucleate myotubes of a “composite” nature: that is, individual myotubes contained labeled nuclei of the donor, side by side with unlabeled nuclei of the host. There was no doubt that the mononucleate myoblasts of the grafts had fused with those of the host species to form the mutlinucleate composite myotubes.In addition to the above determinations, the method of thymidine labeling has proven to be a satisfactory method of tracing, in the context of the intact organism, somitic cell derivatives up to the feeding larval stage. Mesenchymal cells from the grafted labeled somitic tissues were consequently found in: dermatomic, sclerotomic and intermyotomic locations; the matrix of the dorsal fin; the limb bud; the abdominal muscles.
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    Journal of Morphology 129 (1969) 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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    Journal of Morphology 129 (1969) 
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    Notes: Each muscle of the third metasomal segment of the male of Nomia melanderi Ckll. is described in detail. The points of attachment of each muscle are compared with their homologs in other pregenital segments and with their homologs in the female. The function desgnated for each muscle describes its action alone or in conjunction with other muscle(s). New names are given to genital muscles by referring in the name to their points of attachment. Each intratergal muscle has homologous points of attachment in the pregenital segments of both sexes. The median tergo-dorsoplical muscle of the seventh segment and the oblique tergo-dorsoplical muscle of the eighth segment have changed their points of attachment. The intrasternal muscles are modified to suit the needs of courtship and mating, thus they are different from their homologs in the female. The spiracular muscles are well developed in all segments except the eighth, where the sterno-spiracular muscle is absent. The extrinsic genital muscles are derived from the intrasternal muscles of the eighth and ninth segments. The parameral and volsellar muscles are reduced in number. The aedeagal muscles, except the aedeago-phallic, have retained similar points of attachment to those found in primitive Hymenoptera. The topography of the metasomal nervous system is reported in detail by following each nerve and nervule to its termination. The study shows that (at least in Nomia) the criterion of nerve-concentration should not be used alone to indicate evolutionary levels. To accommodate the morphological changes in the terminal segments the Anterior and Posterior Lateral Nerves have migrated to new locations. The pattern of nerve topography (even at the nervule level) is homologous both in the different pregenital segments and between the sexes. The fact that homology does not exist between the external genitalia of the male and the modified ovipositor of the female supports the thesis that the male genital capsule is of phallic rather than prephallic origin. A pair of intersegmental membrane glands located between the seventh and eighth sterna is described. These glands may be the source of a pheromon responsible for gregariousness among “sleeping” males.
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  • 77
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Differentiating oocytes and associated follicle cells of two species of amphineurans (Mollusca) Mopalia muscosa and Chaetopleura apiculata have been studied by techniques of light and electron microscopy. In addition to the regularly occurring organelles, the ooplasm of young oocytes contains large, randomly situated, basophilic regions. These regions are not demonstrable in mature eggs.As oocytes differentiate, lipid, pigment and protein-carbohydrate yolk bodies accumulate within the ooplasm. Concomitant with the appearance of pigment and the protein carbohydrate containing yolk bodies, the saccules of the Golgi complex become filled with a dense material. Associated with the Golgi complex are cisternae of the rough endoplasmic reticulum which are filled with an electron opaque substance which is thought to be composed of protein synthesized by this organelle. That portion of the cisternae of the endoplasmic reticulum facing the Golgi complex shows evaginations. These evaginations are thought to finalize into protein containing vesicles that subsequently fuse with the Golgi complex. Thus, the Golgi complex in these oocytes might serve as a center for packaging and concentrating the protein used in the construction of the protein containing pigment or protein-carbohydrate yolk bodies. The suggestion is made that the Golgi complex may also synthesize the carbohydrate portion of the formentioned yolk bodies.In an adnuclear position in young oocytes are some acid mucopolysaccharide containing vacuolar bodies. In mature eggs, these structures are found within the peripheral ooplasm and we have referred to them as cortical granules. There is no alteration of these cortical granules during sperm activation.
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  • 78
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    Journal of Morphology 127 (1969) 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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  • 79
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    Journal of Morphology 127 (1969), S. 7-39 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A structure for a generalized insect epidermal cell during the formation of the epicuticle is proposed, based on studies of several different epidermal cell types. The protein epicuticle is defined as the dense homogeneous layer below the cuticulin. The formation of the protein epicuticle involves secretory vesicles arising in Golgi complexes, and marks an interlude in the involvement in cuticle formation of plasma membrane plaques. The plaques are concerned in cuticulin formation before and in fibrous cuticle formation after the deposition of the protein epicuticle.The epidermis is characterized by the possession of a cytoskeleton of microtubules and a matrix of microfibers. In the elongated cells forming bristles and spines, the microfibers are often oriented in bundles with an axial banding which repeats every 120 Å. The microtubules are also arranged in columns with a trigonal packing and center to center spacing of about 800 Å. These cytoskeletal structures separate the other organelles into channels which may restrict the pathways open for the movement of secretory and pinocytotic vesicles. The protein epicuticle arises from the secretory vesicles which discharge at the apical surface. The contents disperse and reaggregate below the cuticulin. The Golgi complexes in the basal and central regions have many secretory vesicles and a small saccular component, differing from those nearer the apex which are smaller and have fenestrated saccules. The small coated vesicles (800 Å in diameter) associated with both sorts of complex, probably move to the apical and basal faces of the cell where they may give rise to the large coated vesicles (2000 Å in diameter) inserted in the plasma membrane. Pinocytosis occurs from both apical and basal faces but most lytic activity is in the apical region. Plant peroxidase injected into the haemocoel is taken up basally and transported to the apical MVBs. The large coated vesicles on the apical face may be concerned in the control of the extracellular subcuticular environment. They appear to fill up and detach, fusing to become the apical MVBs.
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  • 80
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Histochemical procedures for acid phosphatase in normal and lens-regenerating eyes of the urodele Diemictylus viridescens demonstrate activity in a variety of structures. In the normal urodele eye, acid phosphatase is present in conjunctival and corneal epithelial cells and associated glands, in blood vessel endothelium and posterior epithelial cells of the iris, in the anterior lens epithelium, and in the cytoplasm of the optic nerve. Acid phosphatase in the lens-regenerating eye is localized in the same structures as in the normal eye as well as in increased amounts in the corneal epithelial cells and stromal macrophages at the lentectomy wound site and in the posterior portion of the developing lens during completion of differentiation of primary into mature lens fibers characterized by loss of many intracellular organelles. On the basis of these histochemical findings, it is proposed that hydrolytic lysosomal enzymes play an important role in the processes of cellular and intracellular destruction and synthesis which occur during Wolffian lens regeneration in the urodele.
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  • 81
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    Journal of Morphology 129 (1969) 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
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  • 82
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The development of the eye in embryos of Rana pipiens raised at two different temperatures was studied in detail from Shumway stage 16 through Shumway stage 25. One clutch of eggs from each of ten different female frogs was divided into two groups, one of which was raised at a temperature of 14°C and the other at 19°C. The 14° to 19° difference falls in the middle of the temperature range for normal development of Rana pipiens as established by Atlas ('35), Moore ('39), and Ryan ('41). Two hundred embryos, one embryo from each of the ten clutches, raised to each of ten stages at 14° or at 19°, were sectioned for microscopic study of the eye region. Descriptions of the morphology and histology of the developing eye are illustrated by photographs and provide a reference to which development of experimental embryos may be compared. A synoptic checklist is provided which specifies the changes occurring at each stage studied.
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  • 83
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    Journal of Morphology 127 (1969), S. 105-112 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A detailed description of the innervation of the individual muscles of the antenna of the centipede Scolopendra morsitans is given. There are six nerves supplying the antennal muscles of each side. The nerve N I consists of 26 bundles of which two are motor, 12 sensory and 12 are mixed. It innervates the intrinsic muscles of the antenna and the antennal sense organs. The nerves N II, N III and N IV innervate the dorsal extrinsic muscles and the nerve N V and N VI the ventral extrinsic muscles.
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  • 84
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    Journal of Morphology 127 (1969) 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 85
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Each statocyst in Apylsia californica contains 13 neurons. The statocyst nerve, which connects each statocyst to the cerebral ganglion, contains only the 13 axons of the statocyst neurons. The size of the statocyst, the number of neurons in the statocyst, and the average axonal diameter does not change even though the statocyst nerve lengthens greatly as the animal enlarges. A description of the statoconia and the supporting cells in this organ has been given. This prepazation may be useful for microelectrode studies designed to test whether the gap and cytoplasmic specializations that are used to identify active synapses, are necessary for all types of chemical synaptic transmission.
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  • 86
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    Journal of Morphology 127 (1969), S. 151-161 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Dense bodies in the heart muscle of Venus mercenaria exist in two forms, free and attached. Free dense bodies morphologically consist of fascicles of thin filaments in parallel array and bound together by a dense, amorphous proteinaceous material. The binding of dense bodies to the cell membrane is effected via connecting filaments of the amorphous material of the dense body which join a condensation of morphologically similar material attached to the inner osmiophilic layer of the unit membrane. This composite of dense body, connecting filaments, membrane condensation and unit cell membrane has been termed collectively the attachment plaque. The attachment plaque is part of an extensive network on the cell surface which obligates that surface to a role in the contractile process. Moreover, this set of attachment plaques imposes an organization and an orientation to most thin filaments of the cell and preserves the contractile axis of the cell.
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  • 87
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Oogenesis and embryonic development in the marine sponge, Haliclona ecbasis, were studied using standard histological procedures.When the oocytes reach a diameter of about 30 μ, nurse cells begin to aggregate around them. Then when the oocytes are about 36 μ in diameter, they begin to engulf the associated nurse cells. Whole nurse cells are engulfed; and although the nucleus of the nurse cells disappears either as or soon after the cells are engulfed, the cytoplasm remains essentially unchanged. The accumulation of these cells within the oocytes most of the cytoplasm is nurse cell cytoplasm.During cleavage of the egg, the engulfed nurse cells are gradually fragmented, but otherwise appear unchanged. At the same time the cytoplasm of the nurse cells is progressively incorporated into that of the blastomeres by what appears to be fusion process. When the latter process is complete, the embryo develops into a typical parenchymula larva.
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  • 88
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    Journal of Morphology 128 (1969) 
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
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  • 89
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: A detailed topography of adrenergic innervation in invertebrates (lobster), low vertebrates (fish, amphibians, reptiles, birds), and nine species of mammals is presented. Flack and Hillarp's specific fluorescent histochemical method using freeze-dried material was used. Phylogenetically, adrenergic innervation appeared earlier under the ciliary epithelium and in the muscle than surrounding the vessels, and in all species many fibers were without any connection to the vessel walls. Adrenergic innervation was very rich in the dilator muscle extending toward the epithelium of the posterior chamber; a surprisingly rich network was found in the sphincter muscle and also in ciliary spaces of some species. Numerous fluorescent mast cells were visualized in the pecten of the bird eye and in the ciliary tissue of the sheep and cow.
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  • 90
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    Journal of Morphology 128 (1969), S. 427-441 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The cytology of the vitellogenic stages in the development of the oocyte of Drosophila melanogaster has been studied using whole mounts and sections of plastic-embedded ovaries and single egg chambers for light microscopy and cytochemistry. The migrations, changes in morphology, and synthetic products of the follicle cells are described as a function of developmental stage. The follicle cells synthesize the egg coverings, the vitelline and chorionic membranes, and elaborate the micropyle and dorsal chorionic appendages. The changing structure of the nurse cell nucleus and changes in organelle composition of its cytoplasm are described. The nurse cells synthesize ribosomes, lipid droplets, and mitochondria. These components pass through the ring canal system into the oocyte, which increases in volume some 200,000 times during its 78 hours of development.
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  • 91
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    Journal of Morphology 129 (1969), S. 17-30 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The heteropteran cibarium forms a sucking pump which conveys fluid foods into the pharynx. The food pumps of Hydrocorisae have the additional function of grinding or filtering particulate matter; they contain ridges, hairs, and sclerotized processes which have probably evolved at least twice among the hydrocorisine families. Aphelocheirus, like the Naucoridae, possesses a modified anteclypeus and a tripartite type of food pump. The main sucking action occurs in the pump's anterior and posterior regions, while the middle region is specialized for grinding and filtering. The anteclypeus has broadened and fused with other parts of the cranium, and is thus braced against the pull of the powerful cibarial dilator muscles. In the Naucoridae the three regions of the pump have the same functions as those of Aphelocheirus. The pumps of the five naucorid genera here studied are structurally very similar to each other but differ considerably from that of Aphelocheirus. Cibarial morphology, as well as respiratory differences, thus supports the contention that Aphelocheirus is not a member of the Naucoridae but should be placed in a separate family.
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  • 92
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    Journal of Morphology 129 (1969), S. 81-87 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The interstitial cells of Pennaria tiarella differentiate exclusively from the central endoderm of the planula. Shortly after their appearance, most of the interstitial cells become cnidoblasts. Subsequently, as the larva transforms into a polyp, both cnidoblasts and interstitial cells migrate from the endoderm, through endoblast and mesoglea, into the ectoderm. It is suggested that some interstitial cells remain in the endoderm and differentiate into the gland and mucous cells of the polyp gastroderm.
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  • 93
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The structure of the “Corneagen,” i.e., the epidermis lying beneath the cornea-lens of the lateral eyes of the adult intermolt Limulus polyphemus was studied with light and electron microscopy.This layer is composed of heavily columnar cells containing a striking number of cytoplasmic microtubules. Many of the microtubules are grouped into compact bundles or fascicles, generally each cell having at least one microtubule bundle. The cornealens end of each cell has numerous microvilli, each with a core of delicate filaments. The crypts between microvilli end in extracellular expansions and plaques of electron dense amorphous material are associated with these terminal expansions. Cytoplasmic microtubules appear to insert into these dense areas.The basal ends of the cells are thrown into many pseudopodial processes which extend into the surrounding extracellular space. The cytoplasm of the pseudopodia is composed largely of microtubules and their associated low density halos.Junctional complexes consisting of zonulae adhaerens and septate desmosomes are present between adjacent cells. Mitochondria, ER, cytoplasmic vesicles, Golgi stacks and other ultrastructural details of the epidermal cells are described. The ultrastructure of a column of pigment free processes lying between the apex of the lens cone and the underlying photoreceptive portion of the ommatidium is also described. Ducts or vessels of uncertain origin are present in the inter-ommatidial spaces.Possible roles played by the microtubules, the significance of their disposition and of their association with the dense subsurface plaques are discussed in terms of intracellular support, epidermis-lens attachment and extracellular pattern determination. In addition, the likelihood of the dense plaques being the site of microtubule assembly is considered.
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  • 94
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    Journal of Morphology 128 (1969), S. 67-93 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The endoskeletal structure supporting the gill-books of Limulus polyphemus has been investigated by means of light and electron microscopy, chemical analysis and x-ray diffraction. This tissue is a cartilage which has significant correspondences with both vertebrate cartilage and plant tissues. Morphologically, the Limulus cartilage resembles certain cellular vertebrate cartilages with relatively scant matrix, and also certain plant parenchyme, collenchyme and sclerenchyme tissues. Of particular interest, was the observation that during cytoplasmic division, a phragmasome-like structure appears between the daughter cells of the dividing gill cartilage cells. This phragmasome-like structure appears to be a precursor of new matrix (cell-wall) formation between the young chondrocytes, in much the same fashion as its counterpart in plant tissues. Perichondrial cells and underlying chondrocytes contain lipid droplets, abundant glycogen and ribosomes, as do corresponding vertebrate cartilage cells. In some of the Limulus cells, glycogen and ribosomes appear to be admixed with lipid, forming aggregates in which all three materials are in intimate intraparticulate relationship. During molting, the number of ribosomes seen in chondrocytes increases. The tissue contains both hydroxyproline and hydroxylysine, and gives a weak x-ray diffraction pattern.
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  • 95
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    Journal of Morphology 127 (1969), S. 475-509 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The rectum of Periplaneta americana L. is lined with cuticle and has six radially arranged cushion-shaped thickenings, the rectal pads, composed of columnar cells. Narrow strips of simple rectal cells lie between the pads. Tall junctional cells form a thin but continuous collar around the pads where they join the rectal cells. The epithelium is surrounded by a layer composed of circular and longitudinal muscles and connective tissue. This layer of muscle and connective tissue is innervated and tracheated, and is separated from the pad surface by a subepithelial sinus. Fluid flowing through the sinus enters the haemolymph through openings in the muscle layer whre large tracheae penetrate. These openings can be sealed by muscle contractions that appress the muscle around the openings against the pad surface. The tracheae pass on into the pads, following basement membrne-lined indentations of the pad surface. Within the pad tracheolar cells send fine branches between the cells. Near the apical and basal surfaces the lateral membranes of pad cells are bridged by septate desmosomes that form a continuous band around the cells. Between apical and basal septate desmosomes is an interconnected labyrinthine system of intercellular spaces. There are three kinds of space, dilations and apical sinuses, both of variable size, and narrow communicating channels about 200 Å wide. The membranes of the latter have mitochondria closely associated with them. Continuity between the system of spaces and the subepithelial sinus is established by the basement membrane-lined invaginations of the basal surface where tracheae penetrate between pad cells. Apical surfaces of the pad cells are highly infolded and are also associated with mitochondria. However, unlike the lateral membranes facing the narrow channels, the apical membranes have a cytoplasmic coating of particles. Both associations of mitochondria with membranes constitute discrete structural entities that are found in many transporting epithelia, and we have termed them “plasmalemma-mitochondrial complexes.” As the rectal pads are organized into systems of spaces that ultimately open in the direction of fluid movement, existing models of solute-coupled water transport can be applied. However, the rectal pads are structurally more complex than fluid-transporting tissues of vertebrates. This complexity may be related to the ability of the rectum to withdraw water from ion-free solutions in the lumen. We present a structural model involving solute recycling to explain the physiological characteristics of rectal reabsorption.
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  • 96
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    Journal of Morphology 127 (1969), S. 1-5 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Tooth attachment in the majority of the bony fish is by ankylosis or fibrous membrane. However, in one group of the osteichthys, the trigger-fish or balistids, tooth attachment is by means of a periodontium composed of a shallow alveolar socket, a periodontal ligament and acellular cementum.Histologically, the balistid periodontal ligament is composed of a dense fibro-cellular connective tissue possessing an abundance of typical fibrocytes, collagen fiber bundles, and oxytalan fibers. The collagen fiber bundles which resemble the principal fiber bundles of the mammalian periodontal ligament are inserted into the bone of the shallow alveolar sockets and are anchored to the teeth by means of a layer of amorphous acellular cementum that covers the radicular dentin. No cementoblasts were found in functional teeth, and epithelial rests are lacking. The mid-central zone of the balistid periodontal ligament is occupied by small blood vessels.
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  • 97
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    Journal of Morphology 129 (1969), S. 307-315 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The hatching threads of praying mantis embryos are silk-like in appearance, but cellular in origin. Their development can be divided into four phases. In phase 1 each embryonic cercus produces a hollow column of cells which is pushed out dorso-laterally, on either side of the embryo, between the epidermis and the chorion. In phase 2 each column becomes transformed into an unbroken helical cellular filament. The terminal five or six cells at the distal end of each filament become permanently attached to the inner surface of the chorion. The cellular arrangement of the filament is superseded by an apparent syncytial condition. In phase 3 the extensive proximal parts of the two filaments become folded into a compact space, flanked by the cerci and styli, at the tip of the abdomen. Throughout phase 4 the filaments remain in two tightly coiled groups, connected to the chorionic attachments by loosely coiled distal regions. Progressive secretion of chitin by, and around, each filament forms a sheath, 1-2 μ thick, which provides the tensile component of the hatching threads. During emergence these threads become unravelled to form a double thread which allows the insect to hang from the ootheca and complete its first ecdysis.
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  • 98
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Biochemical assay of acid phosphatase in normal and lens-regenerating eyes of the urodele Diemictylus viridescens, using p-nitrophenyl phosphate as substrate, demonstrates both soluble and lysosomal fractions of the enzyme. While the specific activity of the soluble fraction remains unchanged during lens regeneration, the lysosomal fraction shows four distinct rises in specific activity during the thirty-day regeneration period studied. These peak activities on the second, eighth, fifteenth, and twenty-second days post-lentectomy apparently correspond to lysosomal activity in the processes of wound healing, iris depigmentation, and lens differentiation which occur during urodele lens regeneration. On the basis of biochemical and histochemical studies as well as observations of morphological changes in the urodele eye as lens regeneration proceeds, it is postulated that there is a significant correlation between these morphological changes and the level and localization of the lysosomal acid hydrolases in the tissues in which the changes occur.
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  • 99
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Median cord development is uniform in six families of Hemiptera and five non-hemipterans. The median cord arises independently from the lateral cords and is histologically distinguishable from the latter throughout development. Intrasegmentally, median cord nuclei possess prominent nucleoli and many small chromatin granules surrounded by clear nuclear sap. This region forms what appear to be glial elements at the midline of the neuropile. Intersegmentally, a spherical clump of eight to twelve large nuclei develops surrounded by dark-staining granular cytoplasm. Each intersegmental clump migrates anteriorly into the preceding ganglionic region but degenerates soon after katatrepsis.
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  • 100
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The present investigation was undertaken in an attempt to determine the role played by the nerve in the regeneration of the lower jaw of the adult newt, Triturus viridescens. The results indicated that the number of nerve fibers normally available at the amputation surface was very low compared with that of the newt forelimb. Furthermore, denervation of the lower jaw reduced the number of nerve fibers available to an extremely low level and maintained the number at a low level for up to four weeks without intervening redenervations. The regenerative events in the denervated and amputated lower jaws were indistinguishable histologically from those in amputated jaws having normal innervation. This presented an apparent exception to the general rule that regeneration of external body parts is dependent on the nerve. Several possible explanations are proposed by which this apparent exception might be explained. The process following amputation might be an exaggerated form of wound healing and tissue regeneration which can occur in the absence of nerves. The tissues of the lower jaw might be more sensitive to the influence of those nerve fibers present. The nerve fibers themselves might be qualitatively different and thus exert a greater influence on the tissues.
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