ALBERT

Notes: Zur quantitativen Beschreibung des Alkylierungsvermögens kernsubstituierter O,O-Dimethyl-O-phenyl-phosphate und -thiophosphate werden die Reaktionsgeschwindigkeiten ihrer Umsetzungen mit Trimethylamin und 4-(4-Nitrobenzyl)-pyridin (NBP) ermittelt und in Beziehung zu den Hammettschen Substituentenkonstanten σ, IR- und NMR-Daten sowie zu pKa-Werten gesetzt.Gute Korrelationen ergeben sich sowohl mit den Substituentenkonstanten σ insbesondere den σ°-Konstanten, als auch mit den chemischen Verschiebungen δCH3O der Estergruppierung. Die ermittelten Reaktionskonstanten ϱ bzw. ϱ° zeigen die Erhöhung des Alkylierungspotentials durch elektronenziehende Substituenten.Eine für praktische Belange brauchbare Abschätzung des Alkylierungsvermögens gelingt mittels δOH, vOH oder der pKa-Werte der phenolischen Esterkomponente als Korrelierungsparameter, während sich hierzu die Valenzschwingungen vP—O—Caryl nur bedingt und die 31P-Verschie-bungen nicht eignen.

Notes: An den symmetrischen und antisymmetrischen SO2-Valenzschwingungen von einigen höheren n-Butyl- und Phenylsulfonen wird Fermiresonanz als Ursache der Bandenaufspaltung nachgewiesen. Zum Nachweis dient die Methode der Lösungsmittelvariation.

Notes: Phosphonsäuremonoalkylester bzw. Phosphonsäuren reagieren mit Epoxiden zu Phosphonsäure-alkyl-β-hydroxyalkyl- 5 bzw. -bis-β-hydroxyalkylestern 9 oder zu höhermolekularen Polyglykolestern. Durch intramolekulare Umesterung entstehen aus 5 bzw. 9 beim Destillieren unter Abspaltung von Alkohol bzw. Glykol cyclische Phosphonsäureester 6 bzw. 11.

Notes: Die Mischassoziationskonstanten von α,β-ungesättigten Estern mit Aromaten werden unter Annahme einer Dimerisierung der Estermoleküle und eines 1:1 Mischassoziats berechnet. Die Reihenfolge der erhaltenen Konstanten kann durch den I- und M-Effekt der elektronegativen Substituenten am Aromaten erklärt werden. Die Mischassoziation beruht auf einer Wechsel-wirkung zwischen dem positivierten β-Kohlenstoffatom der Ester und dem π-Elektronensystem des Aromaten.

Notes: 2-Aminothiophen-3-carbonsäureester 1 reagieren mit Natriumalkoholat unter Ringöffnung und Recyclisierung zu 2-Hydroxy-3-cyan-thiophenen 2, von denen einige in Substanz als tautomere Δ3-Thiolenone-(2) vorliegen. Besitzen diese eine freie 5-Position, so kondensieren sie mit Aldehyden zu den 5-Arylidenthiolenonen-(2) 3, kuppeln mit Diazoniumsalzen sowie oxydativ nach HÜNIG und lassen sich zum Aufbau von Oxonolen 5 heranziehen sowie unter Dehydrodimerisierung zu 5,5′-Bi-Δ3-thiolenon-(2)-ylidenen 6 oxydieren. Verbindung 2c ist O-alkylier- und -acylierbar.

Notes: Es werden die NIR-Spektren von 58 gesättigten und aromatischen Kohlenwasserstoffen (KW) im Bereich der 2. Oberschwingung von 8000 bis 9000 cm-1 interpretiert. Daraus wird eine Strukturgruppen-Analysenmethode für gesättigte und aromatenhaltige KW-Gemische abgeleitet.Die mittleren Abweichungen der Strukturgruppengehalte betragen bei CH3-Gruppen ±0,27, CH2-Gruppen ±0,48, CH-Gruppen in gesättigten Strukturen ±0,38 und aromatischen CH-Gruppen ±0,19.Das ursprünglich für unverdünnte, flüssige Proben entwickelte Verfahren kann durch Aufnahme der Spektren bei Temperaturen über dem Schmelzpunkt der Probe auch zur Analyse fester KW-Gemische eingesetzt werden.Die Methode wird bezüglich ihres Informationsgehaltes mit anderen Strukturgruppen-Analysenmethoden verglichen, und Anwendungsbeispiele werden diskutiert.

Notes: Die Geschwindigkeit der C—N-Spaltung bei N-Methyl- und N-äthylformanilid in wäßriger Schwefelsäure sinkt stark mit der zunehmenden Acidität des Mediums, was für das Vorherrschen der Hydrolyse im Verhältnis zur Decarbonylierung spricht. Die geringen CO-Mengen sind der Decarbonylierung der gebildeten Ameisensäure zuzuschreiben. Das Formanilid mit einem freien Wasserstoff am Stickstoffatom reagiert viel schneller auf beiden Wegen.

Notes: Die aus verschiedene Edelmetallen und Trägerkohlen unterschiedlicher Textur hergestellten Katalysatoren weisen eine unterschiedliche Hydrieraktivität gegenüber Nitrogruppen auf. Von den eingesetzten Katalysatoren besitzt der Pt/Rh-Norit SX-Kohle-Katalysator die größte Aktivität. Dabei besteht eine Relation zur Größe der zugänglichen inneren Oberfläche der Kohle für organische Moleküle (Methylenblau-Methode). Von den untersuchten Kohlen stellt die Norit SX-Kohle den besten Träger sowohl für Palladium als auch für Platin und Platin/Rhodium dar. Die Norit SX-Kohle besitzt das kleinste Schüttgewicht, das größte Adsorptionsvermögen für Methylenblau, eine hohe Benetzungswärme in Benzol und den geringsten spezifischen Widerstand.Die Hydriergeschwindigkeit der Natriumsalze der m-Nitrobenzolsulfonsäure und der 4,4′-Dinitrostilben-2,2′-disulfonsäure ist in wäßriger Lösung abhängig von der Katalysatormenge, der Konzentration der Nitroverbindungen und vom pH-Wert. Die Reduktion verläft bei beiden Substraten in konzentrierterer Lösung nach einer Reaktion nullter Ordnung in bezug auf die Nitroverbindungen. Sie nähert sich mit steigender Verdünnung einer Reaktion erster Ordnung bezüglich der Nitroverbindungen. Die größten Reaktionsgeschwindigkeiten werden bei pH-Werten zwischen 3 und 5 erzielt. Der stufenlose Verlauf der Reduktion wird ebenfalls durch den Verlauf des Katalysatorpotentials während der Hydrierung bestätigt. An vergifteten Katalysatoren stellt sich das reversible Katalysatorpotential nicht ein.Die Platin/Rhodium-Kohle-Träger-Katalysatoren haben größere spezifische Widerstände als die entsprechenden Trägerkohlen. Durch elektronenmikroskopische Untersuchungen an 5% Edelmetall-Kohle-Katalysatoren, die durch Reduktion von Edelmetallsalzen mit Formaldehyd in alkalischer Lösung in Gegenwart der Träger hergestellt wurden, können auf dem Kohleträger keine Edelmetallkristallite nachgewiesen werden.

Notes: Rac. α-(Alkyl-, Aralkyl- und Arylacylamino)-propiophenone 1 werden von verschiedenen Kryptobasen stets zu entsprechenden (+) 2-Amino-1-phenylpropanolen-(1) 2 mit threo-Konfiguration reduziert. Die Reduktionsmittel Aluminiumisopropylat, auch im Gemisch mit Chloralu-minium-diisopropylat, oder Natriumborhydrid bewirken keinen Unterschied im sterischen Resultat.

Notes: Die Lösungsmittelabhängigkeit der Addition von Phenolen und N-Methylanilinen an Arylcyanate wurde kinetisch untersucht. Aus dem Vergleich der Geschwindigkeitskonstanten geht hervor, daß steigende Lösungsmittelpolarität die Reaktionsgeschwindigkeit sowohl für die Amin- als auch die Phenol-Addition herabsetzt (lgk = a - b · ET). Die Lösungsmittelaktivitätskoeffizienten weisen aus, daß der reaktionsverlangsamende Effekt durch eine bevorzugte Solvatation der Ausgangszustände hervorgerufen wird. Die Übergangszustände sind nur gering und in den untersuchten Lösungsmitteln annähernd gleich solvatisiert. Aus einem Vergleich der HAMMETT-Beziehungen lassen sich ϱ-Werte für die unterschiedliche Lösungsmittelbeeinflussung des elektronischen Substituenteneffekts auf Arylcyanate, Phenole und Arylamine ableiten.

Notes: Bei der katalytischen Reduktion von chlorsubstituierten aromatischen Nitroverbindungen wird die hydrogenolytische Abspaltung des Chlors sowohl durch die Edelmetall-Komponente, als auch durch die Textur des Kohle-Trägers eines Edelmetall-Träger-Katalysators beeinflußt. Durch die gleichzeitige Verfolgung des zeitlichen Verlaufs der Hydriergeschwindigkeit und der Katalysatorbezugsspannung läßt sich ein Katalysator auf seine Brauchbarkeit für die katalytische Reduktion von halogensubstituierten aromatischen Nitroverbindungen zu den entsprechenden halogensubstituierten Aminoverbindungen prüfen. Die Palladium-Kohle-Trägerkatalysatoren spalten das Chlor in jedem Falle vollständig ab.

Notes: Von den geprüften Katalysatoren besitzt der Pt/Rh-Norit SX-Katalysator für die Reduktion von aromatischen Nitroverbindungen zu den entsprechenden Aminoverbindungen auch in methanolischer Lösung die größte Aktivität. Die Hydrierung erfolgt dabei stufenlos. Eine Ausnahme bilden jedoch die Nitrobenzoesäuren und deren Derivate. Sie werden stufenweise hydriert. Die Änderung der Hydriergeschwindigkeit tritt nach Aufnahme von zwei Molen Wasserstoff je Mol Substrat auf; dies entspricht einer Reduktion bis zur Phenylhydroxylaminstufe, die nachgewiesen werden konnte. Beide Reaktionsstufen unterscheiden sich auch durch ein unterschiedliches Katalysatorpotential.Im Gegensatz dazu werden die Nitrobenzoesäuren über Raney-Nickel sowie die Natriumsalze der Nitrobenzoesäuren in wäßriger Lösung auch in Gegenwart von Edelmetall-Kohle-Trägerkatalysatoren stufenlos hydriert. Die Hydriergeschwindigkeit unterschiedlich substituierter aromatischer Nitroverbindungen hängt von Art und Stellung der Substituenten ab. Als Lösungsmittel eignet sich für die Hydrierung von Nitroverbindungen besonders Methanol. Die Hydriergeschwindigkeit ist bei gleichen Substraten in Methanol annähernd um den Faktor 2, 7 größer als in Wasser.

Notes: Butanolide 1a - d mit kurz- und langkettigen Alkylgruppen in γ-Stellung und Diäthylaluminiumchlorid reagieren vorwiegend zu isomeren ungesättigten Säuren 3 - 5. Durch Ozonolyse wird die Lage der Doppelbindung bestimmt. Der Mechanismus dieser Reaktion wird auf Grund von bisher bekannten Ergebnissen, durch Umsetzung eines deuterierten Butanolids und durch kinetische Messungen aufgeklärt. Dimethyl-aluminiumchlorid reagiert unter diesen Bedingungen gleichartig.Umsetzungen aromatisch substituierter Butanolide 1e-g mit Diäthyl-aluminiumchlorid führen dagegen zu zwei gesättigten Säuren 8, und 9; Dimethyl-aluminiumchlorid ergibt nur eine alkylierte Säure 10.Die Butenolide 2a, b erweisen sich als äußerst stabil und ergeben sowohl mit Diäthyl-aluminiumchlorid als auch mit Dimethyl-aluminiumchlorid in niedrigen Ausbeuten nur ungesättigte Säuren 11a, b.In Gemischen reagieren Äthyl-aluminiumdichlorid und Diäthyl-aluminiumchlorid mit Butanoliden 1 wie selbständige Verbindungen.

Notes: Es wird die Darstellung von 10β-heterosubstituierten Testosteron-Analogen 6 aus entsprechend substituierten Östran-3β,5α, 17β-triolen 1 und 3,3-Äthylendioxy-östran-5α,17β-diolen 2 beschrieben.Die Überführung der Triole 1 in die Testosteron-Analogen 6 erfolgt durch selektive Oppenauer-Oxydation in 3-Stellung und anschließende Dehydratisierung oder durch Jones-Oxydation zu den 3,17-Dionen 3, anschließende Dehydratisierung und Reduktion der Ketogruppe am C-17. Ausgehend von den Ketalen 2 werden die Testosteron-Analogen 6 durch Ketalspaltung und anschließende Dehydratisierung erhalten.

Notes: Bei der Verdrängung von Isobuten aus Triisobutylaluminium durch Styrol ist im Gegensatz zu den bisher bekannten Verfahren ein vollständiger Umsatz zu Tri-(phenyläthyl)-aluminium auch ohne Katalysator zu erzielen, wenn die Polymerisation des Styrols durch Lichtausschluß verhindert wird. Im Reaktionsprodukt beträgt das Isomerenverhältnis von 1- zu 2-Phenyläthylgruppen nach gaschromatographischer Untersuchung der hydrolysierten Oxydationsprodukte im Mittel 35:65. Partielle Oxydationen weisen auf die bevorzugte Reaktion der 1-Phenyläthylgruppen des Tri-(phenyläthyl)-aluminiums hin. Zahlreiche Nebenprodukte (Diphenylbutane und -butene, Diphenylbutanole sowie 1,3-Diphenylbutanon-1) wurden mit Hilfe von Gaschromatographie, IR-NMR- und Massenspektren identifiziert. Deuterolyse des Tri-(phenyläthyl)-aluminiums führt zum Gemisch zweier unterschiedlich deuterierter Isomerer des Äthylbenzols; aus den NMR-Spektren ergibt sich eine durchschnittliche Isomerenverteilung von 37:63 für 1-zu 2-Phenyläthylaluminium. Tri-(phenyläthyl)-aluminium und Aluminiumtrichlorid reagieren in entsprechenden Molverhältnissen zu Di-(phenyläthyl)-aluminiumchlorid bzw. Phenyläthyl-aluminiumdichlorid, die im Hochvakuum destillierbar sind.

Notes: Die Retentionsindices von 4-Alkylthiacyclohexenen-(3) 4a-d und von 4-Alkylidenthiacyclohexanen 3a-d wurden auf Trennflüssigkeiten verschiedener Polarität (Squalan, Carbowax, Polyester, Phenylsilikonöl und Nitrilsilikonöl) im Temperaturbereich von 110° bis 130°C gemessen. An Hand der daraus erhaltenen Homomorphiefaktoren und der ΔI-Werte werden Zusammenhänge zwischen Molekülstruktur und Retentionsverhalten diskutiert. Eine gaschromatographische Zuordnung der exo/endo-Isomeren ist auf Grund der höheren Retentionsindices und ΔI-Werte der endo-Isomeren möglich.

Notes: Nach dem Prinzip der KRÖHNKEschen Aldehydsynthese werden p-Dimethylaminophenyl-nitrone N-substituierter Glyoxylanilide 7a-f dargestellt, die in verdünnten Mineralsäuren zu N-substituierten Isatinen 11a-f umgewandelt werden. N-substituierte Anilinothiocarbonylmethylpyridiniumsalze 6a-e werden entweder aus α-Chlorthioacetaniliden 5 oder durch Umsetzung N-substituierter Anilinocarbonylmethylpyridiniumchloride 2 mit P2S5 gewonnen und bilden über entsprechende Phenylnitrone 8a-c bisher nicht zugängliche N-substituierte 2-Thioisatine 12a-c. Als Zwischenprodukte der Reaktion treten N-substituierte Glyoxylanilide auf. Semicarbazone, Thiosemicarbazone und Isothiosemicarbazone von N-substituierten Isatinen, 2-Thioisatinen und Glyoxylaniliden werden beschrieben.

Notes: Allylvinyläther 1, Acrylsäureallylester 2, Heptadiensäuremethylester 3, Acrylsäure-N-allylamide 4, Diallylalkylamine 5 und Triallylamin 6 werden auf ihre Fähigkeit hin untersucht, in Gegenwart von Basen zu isomerisieren.Während die Verbindungen 1, 3 und 5 sich mit Basen isomerisieren lassen, beobachtet man bei der Behandlung von 2 und 4 mit NaOCH3 in Benzol bzw. Dimethylformamid Additionsreaktionen. Eine intramolekulare C—C-Verknüpfung konnte nicht festgestellt werden.Triallylamin 6 läßt sich mit K/Al2O3 bzw. Na/Al2O3 isomerisieren und zu einem Δ2-Tetrahydropyridin cyclisieren.

Notes: Die Thiophosphorsäureamide Et2NP(S)(NH2)2 1 und (Me2N)2P(S)NH2 3 reagieren mit Phosgen in benzolischer Lösung quantitativ zu kristallinen, außerordentlich feuchtigkeitsempfindlichen Phosphoniumverbindungen [Et2NP(NH2)2Cl]Cl 2 bzw. [(Me2N)2P(NH2)Cl]Cl 4. Das chemische Verhalten der Äthylverbindung wird näher untersucht.

Notes: Substituierte 1,2-Diamino-6-methylmercaptopyridiniumsalze 2 reagieren mit methylenaktiven Nitrilen zu substituierten 2,7-Diaminopyrazolo[2,3-a]pyridinen 3, die auch aus substituierten 2-Amino-5-cyanmethylenthiopyranen 5 und Hydrazin erhältlich sind. Die Umsetzung von 2 mit Cyanamid führt analog zu 2,7-Diamino-s-triazolo[2,3-a]pyridinen 8. In Gegenwart von sek. Aminen kondensiert 2 zu Diaminodipyrido[2,1-a;2,1-d]tetrazinen 9.

Notes: Die Möglichkeiten zur Aktivierung von Kohlenmonoxid in quadratisch-planaren Rhodium- und Iridiumkomplexen des Typs MXCOL2 werden mit Hilfe eines iterativen erweiterten HÜCKEL-Verfahrens untersucht. Je nach der Elektronenstruktur der Liganden X und L wird das komplex-gebundene Kohlenmonoxid unterschiedlich stark negativiert und polarisiert, während dem zentralen Metallatom eine Transmitterrolle zufällt.Liganden mit starken π-Akzeptoreigenschaften erhöhen die elektrophile Reaktivität des Liganden CO gegenüber dem freien Molekül, binden den Liganden aber gleichzeitig fester an das Metall. Donorsubstituenten verstärken die reduktive Kraft der Komplexe, verschlechtern jedoch die lokale elektrophile Reaktivität des Carbonylkohlenstoffs, so daß in beiden Fällen fördernde und hemmende Reaktionseinflüsse nebeneinander stehen. Die erhaltene Elektronenverteilung spiegelt bekannte experimentelle Eigenschaften der Komplexe befriedigend wider.

Notes: Es wird die Synthese von N-Sulfinyl-4-aminobenzophenon 1 beschrieben. 1 wird durch Kondensation mit Kalium-tert.-butylat in N,N′-Bis(4-benzoylphenyl)-schwefeldiimid 2 und unter Katalyse von Bortrifluorid-Ätherat in Poly-α-(p-phenylen)-benzylidenamin 3 übergeführt.

Notes: Peptide mit N-terminalem Norarginin (γ-Guanido-α-aminobuttersäure) lassen sich nach den üblichen Methoden der Peptidsynthese nicht darstellen. Die Alkalilabilität des NG-Nitronorarginins verhindert die α-Acylierung und führt ebenso wie die für die Peptidsynthese notwendige Aktivierung der Carboxylgruppe wegen der ausgeprägten Tendenz zu intramolekularen Ringschlüssen vorzugsweise zu cyclischen Produkten. Die Synthese von Norarginylpeptiden gelingt dagegen glatt, indem zunächst die entsprechenden Peptide der α,γ-Diaminobuttersäure mit selektiv abspaltbaren Schutzgruppen dargestellt und in diese nach Abspaltung der γ-Schutzgruppe die Nitroguanidogruppe eingeführt wird. Auf diese Weise wurde Nα-Z- bzw. Nα-Boc-NG-Nitronorarginyl-prolin synthetisiert und aus diesem das Nα-Z-NG-Nitro-norarginyl-prolyl-prolyl-glycinhydrazid gewonnen. Es stellt die durch Norarginin modifizierte N-terminale Peptidsequenz des Bradykinins dar.

Notes: Der massenspektroskopische Abbau der 1-Aryl-3-[3-methyl-benzthiazolinyliden-(2)]-triazene 1, die in zwei isomeren Formen existieren, wird untersucht. Die Isomerenpaare unterscheiden sich z. T. signifikant in der Intensität, mit der die Primärfragmentierungen ablaufen. Die Unterschiede werden im Hinblick auf eine mögliche cis-trans-Isomerie diskutiert.

Notes: Es wird die Synthese von 9 neuen photochromen Verbindungen beschrieben, die sich von 2-(2′,4′-Dinitrobenzyl)-pyridin 1 durch Einführen von weiteren Substituenten in die Methylengruppe, in 5′-Position des Phenylringes und in Position 4 des Pyridinringes ableiten.Die Synthese der α-Substitutionsprodukte erfolgt durch NBS-Bromierung und Mannich-Reaktion von 1 und durch Folgereaktionen der α-Bromverbindung und der Mannich-Base. In 5′- und 4-Position substituierte Dinitrobenzylpyridine werden durch Nitrierung der entsprechenden substituierten Benzylpyridine erhalten. 2-(2′,′ 4-Dinitro-5′ -natriumsulfonatobenzyl)-pyridin 9f ist wasserlöslich, thermisch stabiler als 1, und die blaue Farbform besitzt eine größere Lebensdauer als die von 1.

Notes: Diketone reagieren mit Palladium (II)-Verbindungen in einer stöchiometrischen Reaktion unter Dehydrierung zu α,β-ungesättigten Diketonen. Aus Cyclohexandionen entstehen die entsprechenden Dihydroxybenzole.

Notes: Ein einfacher Zusammenhang zwischen 13C-NMR-chemischer Verschiebung δ und π-Elektronendichte q wird auch bei heterocyclischen und verzweigten organischen π-Elektronensystemen gefunden, wenn der Einfluß der dem betrachteten Kohlenstoffatom benachbarten Atome auf die σ-Elektronenverteilung berücksichtigt wird.

Notes: Es wird über Darstellung und Eigenschaften chelatbildender Blaugrünkuppler berichtet, die sich vom 5-[1-Hydroxy-naphthoyl-(2)-amino]-2-methyl-imidazo[4,5-h]-chinolin 1 ableiten. Das Farbkupplungsverhalten dieser Verbindungen und vor allem ihre Chelatbildungstendenz wird mit denen von 1-[1-Hydroxy-naphthoyl-(2)-amino]-naphthalin 2a, verglichen, um einen geeigneten Indikator für potentielle MeOn-Koordination anstelle der hier erwünschten MeNn-Koordination zu haben. Auf diesem Wege gelang es nachzuweisen, daß Verbindung 1 vorwiegend MeNn-Koordination betätigt, was auch durch die erfolgreiche Farbkupplung der Metallchelate dieses Liganden mit p-Phenylendiaminderivaten in Gegenwart eines Oxydationsmittels bzw. mit p-Nitrosodimethylanilin bewiesen werden konnte. Über Absorptionsverhalten und einige Farbstoffeigenschaften der Metallchelatfarbstoffe im Vergleich zu den metallfreien Verbindungen wird berichtet.

Notes: Für die Reaktion von Nitrosomethan mit Kohlenmonoxid und Komplexen des Typs MXCOL2 als Katalysatoren wird im ersten Schritt eine Addition der Nitrosoverbindung an den Metallkomplex angenommen. Wir berechneten einen relevanten Ausschnitt der Potentialfläche des Adduktes unter Variation der Liganden X und L für RhXCOL2-Komplexe im EHT-Formalismus. Im Addukt kommt es durch einen Ladungstransfer vom Komplex auf die Nitrosoverbindung zu einer Destabilisierung der N = O-Doppelbindung. Gleichzeitig wird eine positive Überlappungspopulation zwischen dem Sauerstoffatom der Nitrosogruppe und dem Kohlenstoffatom der Carbonylgruppe berechnet. Das gefundene Reaktionsprofil zeigt weiterhin, daß σ- und π-Akzeptorliganden L die Desoxygenierung der Nitrosoverbindung begünstigen. Auf Grund der erhaltenen Ergebnisse wird ein Mechanismus für die Carbonylierung von Nitrosoverbindungen diskutiert.

Notes: Die Reaktionsgeschwindigkeitskonstanten dritter Ordnung der Reaktion von Bromcyan mit substituierten Anilinen unter dem katalytischen Einfluß von Wasser wurden in wäßrigem Aceton bestimmt. Die langsamste Stufe der Reaktion ist der nucleophile Angriff des Anilins an ein Assoziat aus Bromcyan und Wasser. Die Reaktion verläuft wahrscheinlich über einen Sechszentren-Übergangszustand, wie aus dem Studium der elektronischen und sterischen Effekte und dem fehlenden Einfluß der Lösungsmittelpolarität sowie den scheinbaren Aktivierungsparametern hervorgeht. Die in diesem Prozeß gebildeten Arylcyanamide tautomerisieren zu Arylcarbodiimiden, welche ein weiteres Molekül Anilin in katalytischer Gegenwart von Wasser addieren und Diarylguanidine ergeben. Für diese zweite Stufe wurde ebenfalls ein Sechszentren-Übergangszustand anhand der elektronischen, sterischen und Lösungsmitteleffekte sowie der scheinbaren Aktivierungsparameter wahrscheinlich gemacht.

Notes: Für die Synthese von 4-Hydroxy-3, 5-di-tert.-butyl-phenylmethan-phosphonsäuredialkylestern 2 werden zwei einfache Verfahren beschrieben. 4-Hydroxy-3, 5-ditert.-butylbenzaldehyd gibt mit Phosphorigsäurediestern und primären Aminen wie erwartet α-aminosubstituierte 4-Hydroxy-3, 5-di-tert.-butyl-phenyl-methanphosphonsäureester 5, während mit sekundären Aminen überraschenderweise in einem Reaktionsschritt hydroxy-arylsubstituierte Methan-bis-phosphonsäureester vom Typ 6 entstehen.

Notes: p-Methyl-, p-methoxy-, and p-chlorobenzophenone condense with dimethyl homophthalate in the presence of sodium hydride to give the expected stereoisomeric half-esters 1 and 2. The (z)-configuration 2 was favoured in the two former ketones, whereas the (E)-configuration 1 prevailed in the latter. Configuration was determined by cyclisation of the derived dibasic acids 3 and 4 to the oxo-indenyl acids 7 and 8, also obtained by the action of aluminium chloride on the anhydrides 5 and 6. Cyclisation of the half-esters gave the indenyl esters 9 and 10. Structures are supported by i.r., u. v., and n. m. r. spectroscopic evidence. The ratio of isomers is interpreted in terms of the relative ease of ring cleavage of the intermediate δ-lactones 11 and 12.

Notes: The title compound 4 underwent Sommelet and Stevens rearrangements induced by a number of bases. Ionization of the thenyl methylene group of 4 to the corresponding ylid 10 was the prevalent process, yielding subsequently N-[2-(2′-thienyl)-2-phenethyl]dimethylamine 12 and N-[α-(o-tolyl)-2-thenyl]-dimethylamine 13. The strong trend of the 2-thenyl ylids to produce large relative amounts of the Sommelet amine was confirmed. Minor products are N-[2-(2′-thienyl)-1-phenethyl]dimethylamine 15 and N-[α-phenyl-2-(3-methylthienyl)]dimethylamine 16 derived from the benzyl ylid 11.

Notes: Durch Kondensation von ω-Nitrocarbonsäureestern 1 - 3 mit aromatischen Aldehyden in Gegenwart von n-Butylamin bzw. Äthylendiamin entstehen ω-arylsubstituierte Nitrovinylcarbonsäureester 5 - 7. Die gleichen Verbindungen können durch Umsetzung von ω-Nitrocarbonsäureestern mit Benzal-n-butylamin dargestellt werden. Die Anwendung von Ammoniumacetat in Eisessig als Katalysator führt dagegen zu 5-Nitro-6-phenyl-piperidonen-(2) 9. Verbindung 9 a wurde mit LiAlH4 zu 2-Phenyl-3-amino-piperidin 10 a reduziert.

Notes: Zur Einschätzung des Alkylierungsvermögens der cyclischen Schwefelsäureester 1,2-Äthylensulfat 1, 1,3-Propylensulfat 2 und 1,3-Butylensulfat 3 wurden die Geschwindigkeiten ihrer Umsetzungen mit 4-(4-Nitrobenzyl)-pyridin (NPB) in Acetophenon bei 20-50°C gemessen und analog ermittelten Parametern des Dimethylsulfats 4, Diäthylsulfats 5, 1,3-Propansultons 6, 1,4-Butansultons 7 und p-Toluolsulfonsäuremethylesters 8 gegenübergestellt. Die resultierende Reaktivitätsabstufung unterscheidet sich z. T. von der, die man bei der Hydrolyse in Wasser erhält, doch erweist sich in beiden Fällen 1,2-Äthylensulfat 1 als jeweils reaktivstes Agens. Aus LD50-Bestimmungen (Maus, i. p.) geht hervor, daß 1,2-Äthylensulfat auch die höchste akute Toxizität der untersuchten Verbindungen besitzt.

Notes: Nach Aufnahme und Interpretation von Massenspektren aller isomeren Octane bei schonenden Anregungsbedingungen (12 eV, etwa 70 °C Ionenquellentemperatur) gelingt deren Einteilung in fünf Gruppen jeweils strukturähnlicher Verbindungen, deren quantitative Bestimmung auf zwei Arten möglich ist: aBestimmung von Gruppen durch Trennbarkeit des Gemischspektrums in Teilspektren, wenn die Gruppenspektren untereinander unabhängig sind;bBestimmung von Gruppen als „Quasikomponenten“ nach der Matrixmethode, vor allem bei Mehrfachbelegung der Auswertepeaks.Die Methode wird erfolgreich bei der Untersuchung eines technischen Paraffingemisches angewendet; mittlere Abweichungen der Ergebnisse werden mitgeteilt.

Notes: Die individuelle Gemischanalyse durch die Kombination von Gaschromatographie und Massenspektrometrie hat im allgemeinen eine starke Datenhäufung in kurzer Zeit zum Ergebnis. Zur raschen und sicheren Interpretation der Massenspektren von Paraffinen wird ein Identifizierungsverfahren für alle isomeren C5—C9-Alkane vorgeschlagen. Es basiert auf Intensitätsvergleichen charakteristischer, nicht unbedingt intensiver Peaks und gestattet eine vollständige Selektion der Verbindungen. Das Verfahren wurde nach der Programmierung für den elektronischen Kleinrechner C 8205/D 4a erstmals praktisch erprobt, und bei allen Testversuchen wurde eine Wiederfindungsrate von 100% gefunden.

Notes: Die 1H-NMR-Spektren des 1,1′-Diäthyl-3-benzoyl-harnstoffs, -thio- und selenoharnstoffs (1a, b, c) werden im Temperaturbereich von +60°C bis -60°C aufgezeichnet und die beobachteten Veränderungen, Verlagerung des NH-Signals und Einfrieren der Rotation um die CN(C2H5)2-Bindung, diskutiert, die Aktivierungsenergien dieser behinderten Rotation berechnet und die Werte bezüglich des Doppelbindungscharakters der Heteroatome O, S, Se analysiert.

Notes: 2-Heteroarylamino-thiazole lassen sich nach der Methode von HANTZSCH aus heteroaromatisch substituierten Thioharnstoffen darstellen. Die UV- und IR-spektroskopische Untersuchung zeigt, daß diese Verbindungen in der Aminoform vorliegen. Sie sind im festen Zustand über N—H…N-Brücken assoziiert, wobei das Ringstickstoffatom des Thiazols als Protonenakzeptor fungiert.

Notes: Die relativen Autoxydationsgeschwindigkeiten von 26 Alkylaromaten (einschließlich Indan und Tetralin) und 6 Olefinen wurden durch Konkurrenzoxydation bei 30 bis 170°C bestimmt. Die relativen Autoxydationsgeschwindigkeiten der untersuchten kernsubstituierten Toluole lassen sich entsprechend der HAMMETT-Gleichung sowohl mit σ wie mit σ+ korrelieren, erwartungsgemäß erhält man relative kleine negative Werte für ϱ. Die untersuchten Olefine werden wesentlich leichter oxydiert als Alkylaromaten. Besonders überraschend ist die hohe Reaktionsgeschwindigkeit von Norbornen, das keine aktivierten Allyl-CH-Bindungen enthält.

Notes: 3-Cyanpyridinthione-(2) 1 reagieren mit Hydroxylamin-O-sulfonsäure zu 3-Cyan-pyridin-(2)-sulfenylaminen 2, die in Gegenwart von Basen sofort zu 3-Amino-isothiazolo[5,4-b]pyridinen 3 cyclisieren. Nebenreaktion ist die Oxydation zu den Di-(pyridyl-2)-disulfiden 4, die bei der Umsetzung von 1 mit Chloramin  -  das nur mit dem 4,6-Dimethyl-3-cyanpyridinthion-(2) 1a zum Isothiazolopyridin 3a reagiert  -  dominiert.

Notes: Die Umsetzung von Cyclopentadien mit Butadien im Temperaturbereich 120-170°C liefert wegen der unvermeidlichen Nebenreaktionen nur etwa 35% exo/endo-2-Vinylbicyclo[2,2,1]hepten-(5), daneben entstehen etwa 3% 4,7,8,9-Tetrahydroinden sowie die Homodimeren des Cyclopentadiens und des Butadiens.Die bei der Umsetzung von Cyclopentadien mit Butadien ablaufenden Parallel- und Folgereaktionen wurden soweit wie möglich getrennt kinetisch untersucht und die Aktivierungsparameter bestimmt.Überraschenderweise liegen bei der Homodimerisierung von Butadien die Aktivierungsparameter der symmetrieerlaubten Bildung von 4-Vinylcyclohexen und die der symmetrieverbotenen Vier- und Achtringbildung sehr nahe beieinander.

Notes: Mit Hilfe der unabhängig bestimmten Geschwindigkeitskonstanten der 11 zu berücksichtigenden Reaktionen lassen sich die Konzentrations-Zeit-Verläufe der wichtigsten bei der Umsetzung von Cyclopentadien mit Butadien entstehenden Produkte nur mit unbefriedigender Genauigkeit berechnen. Aus den experimentellen Konzentrations-Zeit-Verläufen lassen sich jedoch mit Hilfe von Optimierungsverfahren (angewandt werden das sequentielle Simplex-Suchverfahren und das Verfahren nach SILLEN) die Geschwindigkeitskonstanten der Einzelreaktionen zurückrechnen, und diese zurückgerechneten Geschwindigkeitskonstanten gestatten eine sehr gut mit den Experimenten übereinstimmende Berechnung der Konzentrations-Zeit-Verläufe.

Notes: Die anodische Oxydation einiger substituierter oder kondensierter Carbazolderivate 1-6 wurde in Acetonitril an Platinelektroden untersucht. Substitution des Carbazols in 3-, 6- und 9-Stellung verhindert die sonst in dieser Position ablaufende anodische Dimerisierung und ermöglicht die elektrochemische Erzeugung von stabilen Radikalkationen. Eine Stabilisierung dieser anodischen Primärprodukte und eine Erniedrigung des Halbstufenpotentials wird auch durch Vergrößerung des π-Elektronensystems im N-p-Anisyl-dibenzo[c, g]carbazol 2, in den Indolo[3,2-b]carbazolen 3 und im 9,9′-Diphenyl-3,3′-dicarbazyl 4 erreicht. Infolge der starken Verdrillung der C—N-Bindung wird hingegen weder beim N-p-Anisyl-carbazol 1 h durch Donor-Substitution noch bei 1,4-Bis-(9-carbazyl)-benzol 5 oder 4,4′-Bis-(9-carbazyl)-biphenyl 6 durch mesomere Effekte eine Veränderung des Halbstufenpotentials oder eine Erhöhung der Radikalionenstabilität im Vergleich zum N-Phenylcarbazol 1 e beobachtet. Die präparative elektrochemische Darstellung von 4 sowie die spektroskopische Untersuchung der Radikalionen einiger Verbindungen werden beschrieben.

Notes: Zu Enzymspezifitätsuntersuchungen wurde das Dodecanucleotid dpT—T—T—T—T—T—C—A—T—C—A—T benötigt. Es wird seine chemische Synthese, ausgehend von den Mononucleotiden dpT, dpC und dpA, beschrieben.

Notes: Norbornen, Bicyclo[2, 2, 1]hepten-(2)-carbonsäure-(5)-methylester, Bicyclo[2, 2, 1]hepten-(2)-carbonsäure-(5)-nitril, 5-Methylbicyclo[2, 2, 1]hepten-(2)-carbonsäure-(5)-methylester und Dicyclopentadien werden von molekularem Sauerstoff leicht oxydiert; als Hauptprodukte bilden sich unter Angriff auf die Norbornendoppelbildung die entsprechenden exo-Epoxide.

Notes: Die 13C-NMR-Spektren von cis-(1) und trans-2-Methoxycarbonyl-cyclohexanol (2) sowie von cis-(3) und trans-2-Methoxycarbonyl-cyclohexylacetat (4) werden mitgeteilt, und die Signalzuordnung aus Substituenteninkrementen wird dargestellt. Aus den zugeordneten Spektren kann die Konfiguration der Verbindungen und ihre Vorzugskonformation abgeleitet werden. Es wird gezeigt, daß eine Hochfeldverschiebung des substituierten C-Atoms nicht notwendigerweise mit axialer Anordnung des Substituenten verbunden ist.

Notes: Die Umsetzung von Bis-(o-phenylendiamin)-kupfer(II)-perchlorat mit Aceton führt zu einem (2,2-Dimethyl-2H-benzimidazol)-kupfer(I)-perchlorat-Komplex 1. Dieser reagiert mit Aceto- und Benzonitril unter Bildung der tieffarbigen Verbindungen C6H4N2C(CH3)2 · CuClO4 · 2 RCN (R = CH3, C6H5). o-Phenylendiaminmonohydrochlorid bildet mit Aceton 2,2,4-Trimethyl-1H-2,3-dihydro-benzo[b]1,4-diazepin-hydrochlorid. Daraus resultiert mit KOH die freie Base 2. Das Vorliegen von 2,2-Dimethyl-2H-benzimidazol im ursprünglichen Cu-Komplex, sowie die Struktur von 2 wurden durch 1H- und 13C-NMR-Spektren gesichert.

Notes: Qualitative Characterization of Isomeric n-Alkene Mixtures by 13C NMR Spectra

Notes: The condensation of methyl 2-thienyl, methyl 2-furyl, and phenyl 2-thienyl ketone with dimethyl homophthalate in the presence of either potassium t-butoxide or sodium hydride as condensing agent, gave predominantly the (z)-half estersThe nomenclature of cis/trans isomers follows the IUPAC Tentative rules, Section E, Fundamental Stereochemistry, J. org. Chemistry 35, 2849 (1970). See also N. R. El-Rayyes, J. prakt. Chem. 315 (2), 300 (1973). (E) = trans-(Heterocyclic ring/CO2CH3) (Z) = cis-(Heterocyclic ring/CO2CH3). The structure and configuration of the products were inferred by chemical and spectroscopic means.

Notes: Nuclei isolated from mouse thymus, kidney, and liver were fixed in ethanol-acetic acetic acid; treated with dilute acid to extract histones; stained by three protein end-group procedures; and measured by scanning, integrating microspectrophotometry. Measurements were also made of nuclei isolated from the same organs and stained by the Feulgen procedure for DNA. Protein end-group procedures included pH 2.8 Biebrich scarlet (for basic groups), mercury orange (for sulfhydryl groups), and mercury orange after thioglycolate reduction (for the sum of sulfhydryl and disulfide groups). With the exception of the comparison between Feulgen-stained 2C liver and kidney nuclei, the integrated extinction values obtained for nuclei of a given organ differed significantly from the measurements of nuclei from other organs, regardless of the staining procedure. Furthermore, the integrated extinction values for 2C nuclei were highest in larger, more vesicular nuclei (from liver and kidney) and lowest in condensed thymocyte nuclei, except in the case of measurements of the disulfide content of the nuclei. In this instance, the values of integrated extinction were highest in condensed thymocyte nuclei, intermediate in kidney nuclei, and lowest in 2C liver nuclei. When 2C, 4C, and 8C liver nuclei were compared, the integrated extinction values of 4C nuclei were found to be approximately twice those of 2C nuclei and half those of 8C nuclei. Exceptions included 8C nuclei whose disulfide and Feulgen values were, respectively, higher and lower than expected. The greater disulfide values and reduced Feulgen values obtained in thymocyte and 8C liver nuclei might be related to a greater degree of chrmoatin condensation in these nuclei, and, therefore, to a reduction or selective restriction of their RNA transcriptional capacities.

Notes: The fine structure of spherulecytes, cell types with large, intracellular membrane-bound vacuoles termed spherules, was investigated in regenerating tips of spines of the sea urchin Strongylocentrotus purpuratus. Two categories of cell types were observed: red spherulecytes and colorless spherulecytes. Red spherulecytes were represented by a single cell type, the eleocyte, while colorless spherulecytes consisted of three morphologically distinct cell types termed morula cells, granulocytes, and vacuolecytes. Eleocytes and morula cells were distributed in both the epidermis and dermis, while granulocytes and vacuolecytes were present only in the dermis. After processing for light and electron microscopy, the spherules of eleocytes typically appeared empty, having lost their content of the red pigment, echinochrome. In contrast, the spherules of morula cells, granulocytes, and vacuolecytes enclosed a variety of granular and other material.The cell types reported in this paper resembled, to various degrees, spherulecytes in the coelomic fluid of echinoids described by other investigators.

Notes: The fine structure of regenerating tips of spines of the sea urchin Strongylocentrotus purpuratus was investigated. Each conical tip consisted of an inner dermis, which deposits and contains the calcite skeleton, and an external layer of epidermis. Although cell types termed spherulecytes containing large, intracellular membrane bound spherules were also present in spine tissues, only epidermal and dermal cell types lacking such spherules are described in this paper.The epidermis was composed largely of free cells representing several functional types. Over the apical portion of the tip these cells occurred in groups, while proximally they were distributed within longitudinal grooves present along the periphery of the spine from the base to the tip. The terminal portions of apical processes extending from some of the epidermal cells formed a thin, contiguous outer layer consisting of small individual islands of cytoplasm bearing microvilli. Adjacent islands were connected around the periphery by a junctional complex extending roughly 200 Å in depth in which the opposing plasma membranes were separated by a narrow gap about 145 Å in width bridged by amorphous material. Other epidermal cells were closely associated with the basal lamina, which was 900 Å in thickness and delineated the dermoepidermal junction; some of these cells appeared to synthesize the lamina, while others may be sensory nerve cells.The dermis at the spine tip also consisted of several functional types of free cells; the most interesting of these was the calcoblast, which deposits the skeleton. Calcoblasts extended a thin, cytoplasmic skeletal sheath which surrounded the tips and adjacent proximal portions of each of the longitudinally oriented microspines comprising the regenerating skeleton, and distally, formed a conical extracellular channel ahead of the mineralizing tip. The intimate relationship between calcoblasts and the growing mineral surface strongly suggests that these cells directly control both the kinetics of mineral deposition and morphogenesis of the skeleton. Other cell types in the dermis were precalcoblasts and phagocytes. Precalcoblasts may function as fibroblasts and are possible precursors of calcoblasts. Closely associated with the basal lamina at the dermoepidermal junction were extracellular unbanded anchoring fibrils 150 Å to 200 Å in diameter. Scattered proximally among dermal cells were other extracellular fibrils, presumably collagenous, about 300 Å in diameter with a banding periodicity of 210 Å.

Notes: Larvae removed at one-day intervals from laboratory infected intermediate hosts provided material for a comparative study of presomal development in Prosthorhynchus formosus (Van Cleave, '18) Travassos, '26, Prosthenorchis elegans (Diesing, 1851) Travassos, '15, and Moniliformis dubius Meyer, '33. Acanthellae begin development soon after entering intermediate hosts' hemocoels, and by the 18th day all three species possess three nuclear masses representing primordia of the proboscis, proboscis receptacle and ganglion, and trunk musculature and genitalia.Presomal development of P. formosus and P. elegans results in structures concurring with morphology of other adult palaeacanthocephalans and archiacanthocephalans. Development of M. dubius, however, differs from that of other archiacanthocephalans in that the muscular receptacle wall lines the entire surface of the nonmuscular sheath, failing to form a ventral cleft characteristic of other archiacanthocephalans. Unlike receptacle protrusor muscles of other archiacanthocephalan species, those of M. dubius spiral around the receptacle as they extend posteriad to attach individually to a pouchlike, muscular thickening at the receptacle's base. These protrusor muscles are distinct from the receptacle wall, as attested by their development alongside neck retractor muscles, not from the receptacle primordium, and the manner in which they are left to trail behind the receptacle when it is drawn anteriorly into the proboscis during larval development. The proboscis receptacle of M. dubius should not be thought of as being double-walled, as envisioned by previous workers.

Notes: The hearts and ascending aortae of 11 Weddell seals, Leptonychotes weddelli, three adult Crabeater seals, Lobodon carcinophagus, two adult Ross seals, Ommatophoca rossi, and one adult Leopard seal, Hydrurga leptonyx, were examined for comparison with terrestrial forms. The Weddell seal specimens were from animals ranging in age from midterm in fetal development to mature adults. All specimens were collected in 1971, 1972, and 1973, from McMurdo Sound and the Ross Sea, Antarctica.The phocid hearts were characteristically broader and flatter than those of other carnivore families and they tended toward bifid apices. The heart form indices (height/circumference) averaged 31.5 compared to 39.0 for felids. The right ventricular chambers of the Antarctic seals were found to average longer in Weddells and narrower in all, than those reported for four other carnivore families. An elastic enlargement was present in the ascending aortae of all seals. The largest diameter of the aortic bulb averaged 25.5 mm more than the base of the aorta in the adult Weddell seals which represented an increase of 72.5% over the base.It is suggested that the general heart form, and especially the ascending aortae, are anatomical adaptations to diving. The compressed heart makes possible unimpaired function when the chest is compressed during deep dives. The aortic bulb maintains mean arterial blood pressure and perfusion of the brain and cardiac tissue during diving bradycardia.

Notes: Jaw movements of albino rats during biting and mastication of relatively hard food were recorded by means of conventional and X-ray cinematography. Mandibular kinetics have been analysed in the context of passive mechanical limits imposed by jaw morphology, particularly of the joints, and by the food itself. Movements have been described in terms of degrees of gape, condylar translation and horizontal rotation of the rami about the symphysis.During biting the condyle remains in the anterior two-thirds of the fossa, moves forward as the jaw opens and the converse. The rami usually spread well apart; the lower incisors are usually approximated. Incised food particles are transported toward the molars by means of coordinated jaw and tongue movements. The prominent palatal rugae of the diastemal region abet this process. In the power stroke of mastication, the mandible shifts forward as the lower toothrows move a little inward; the condyles occupy the posterior two-thirds of the fossa. All movements seen were bilaterally symmetrical. Simultaneous chewing occurred on both sides.It is suggested that the lingual components in the primarily anterior power stroke enhance grinding efficiency.A movable symphysis appears to be of critical importance in facilitating this type of mastication.

Notes: The integument of the paddlefish (Polyodon spathula) is unusual as a relatively small amount of mucus is produced by epithelial cells that are not modified into regular mucous gland cells. A thick compact epidermis and dermis compensate for the slight amount of mucus secreted.Paddlefish have a variety of scales formed of concentric bony lamellae containing osteocytes. There are five kinds of scales: dorsal and ventral fulcra on the caudal fin, rhomboidal scales on the caudal lobe, horny denticles over the pectoral girdle, calcareous denticles on the trunk, and anchor-shaped plates on the rostrum. Except for the fulcra, the scales are undoubtedly vestigial.The numerous surface pits on the rostrum, head, operculum, and throat are epithelial invaginations which are not connected to lateral line canals. No nerves lead to the pits. The spherical to cuboidal and often ciliated cells at the base of the pits are considered to be aplasic cells of unformed neuromasts.

Notes: Freshwater sponges of the family Spongillidae reproduce sexually through formation of a parenchymula larva. The cytochemical characteristics of parenchymula larval metamorphosis  -  beginning with the blastula and terminating with the motile escape stage  -  for the spongillid Eunapius fragilis (Leidy) have been defined using both absorption and fluorescent cytochemical methods, particularly those demonstrating protein end-groups. Morphogenesis of the parenchymula larva of E. fragilis involves the interrelated processes of cytodifferentiation and mobilization of reserve materials. Larval development has been categorized into five stages, from blastula (stage I) through the escape stage (stage V). Parenchymula development is characterized by morphogenetic precocity, a fact influencing the rate of mobilization of cytoplasmic reserves, cytodifferentiation, and the fate of individual cell types. With attainment of the stage V parenchymula, the larva is, essentially, a mobile adult sponge exhibiting flagellated chambers, canal systems, a well defined connective tissue stroma, a diverse cell population consisting of specialized elements and a totipotent archeocyte reserve, and a terminal epitheliocyte line. The present study recognizes differences in development within the spongillids as well as within more remote poriferan taxa  -  emphasizing the need for detiled understanding of particular processes in individual species before proposing major generalizations about development in this ancient but evolutionally specialized group.

Notes: In Mytilus californianus, root lamellae of the byssus stem are formed by two morphologically distinct exocrine cell types. Type 1 cells contain large ellipsoid granules which are ultrastructurally identical to those of the collagen gland associated with byssus thread formation: these granules are secreted only at the base of the stem generator. Type 2 cells contain small cylindroid granules which are secreted only from the lateral surfaces of generator septa. The resultant matrix is biphasic because the two secretions are incompletely mixed. Lamellar sheets of matrix are propelled outward by the action of cilia and are molded into a cylinder at the neck region of the stem. However, the stem retains a lamellar pattern.Byssus threads are attached to the stem by flattened rings formed from thread material which is secreted into the cervical crevice surrounding the neck.The microanatomy of the stem forming region is described and a new term, “stem generator,” is proposed for this organ.

Notes: As in other arthropods the exoskeleton of arachnids is subjected to loads generated by external stimuli and behavioral activities. Far from being mere by-products of various activities such loads act as signals for mechanoreceptors capable of detecting minute displacements caused by them in the cuticle. In arachnids the slit sense organs serve in this capacity.Spiders have the most elaborate system of slit sense organs. Our previous studies clearly pointed to a functional significance of their specific location and orientation, as well as degree and type of aggregation (isolated, grouped, compound or lyriform) on respective body parts.The present study extends our work to the slit sense organs of scorpions. It gives a detailed account of the topography of the organs on the walking legs. In general slits are less orderly arranged on the legs of scorpions than on those of spiders. In the scorpion they never aggregate to form lyriform organs. Instead there are groups at comparable locations forming much more irregular, but still specific patterns. Isolated slits are more numerous on the scorpion leg, but are also less regularly distrubuted there. A common feature of the majority of slits on both the spider and the scorpion leg is their position on the lateral surfaces and their orientation roughly parallel to the long axis of the leg.

Notes: The spermatozoon of Cucumaria pseudocurata is unique among those of the echinoderms in that it is tabloid in shape, i.e., elongated and dorsoventrally compressed. The sperm consists of a dorsal surface which contains an extensive striated rootlet-like structure located within a dorsal groove and a ventral surface which contains a medially situated acrosome. A single mitochondrion lies at the base of the nucleus. The flagellum is unusual in that a 9 + 3 tubular arrangement is observed in the mid-tail region.The acrosome consists of an acrosomal granule bounded by a limiting membrane and a surrounding periacrosomal layer. The granule is irregular in shape with the anterior-posterior surfaces flaring out, forming pockets in the periacrosomal material. The ventral granule surface bulges forming a close association with the plasma membrane. The dorsal surface is indented. Ventral to the depression (within the granule) is a small area containing a particulate-fibrous material. To the inside of the granule limiting membrane there is a second membrane-like structure (incomplete) which extends from the anterior-posterior surfaces around the dorsal face of the granule. Dorso-medial to the granule the periacrosomal layer contains a particulate-fibrous region lodged within the granule depression. This material is presumably the precursor of the acrosomal filament.Prominent cytoplasmic folds extend off from the basal flagellar region. The proximal and distal centrioles are situated perpendicular to one another within the mitochondrion. Centriolar satellite materials are associated with both centrioles. Toward the base of the tail the satellite of the distal centriole consists of nine radiating arms extending at an angle of 45° to the axis of the centriole. Each arm terminates in a dense thickening. The striated rootlet extends anteriorly from the distal centriole to just below the level of the acrosome.

Notes: The ecdysial glands of mature male Libinia emarginata are pale, yellowish organs composed of lobes of epithelial cells having oval nuclei which are often eccentric and which have one or two nucleoli containing amorphous granular material and coarse strands. The plasma membrane bordering the basal lamina consists of invaginations containing microtubules which may serve to increase the surface area for metabolic exchange. Masses of smooth endoplasmic reticulum and associated vesicles are scattered throughout the cytoplasm. Two or more vacuoles may coalesce. Larger vesicles lie close to the cell surface. Numerous mitochondria with tubular cristae surround the nucleus and frequently are associated with SER. A few Golgi complexes consisting of flattened sacs, cisternae or vesicles, lipid droplets and free ribosomes were seen. Adjacent plasma membranes may be in close apposition or separated by a space filled with vesicles, granules, or blood or supporting cells. This type of ultrastructure is associated with steroid-secreting cells.

Notes: Recent behavioral studies have shown the primary organ of prehension used in capturing prey to be the claw equipped forelimbs. In light of its functional importance, the claw retractile mechanism for 15 felid species is described and its function studied. The anatomy of the claw retractile mechanism for felids is then compared to that of other carnivorans.For felids, claw retraction is mechanically possible due to the unique shape of the middle and distal phalanges. Claw retraction, however, is a function of the dorsal elastic ligaments and not of the forearm extensor muscles. The resistance provided by these ligaments allows for flexion of the wrist and digital joints without claw protrusion. Moreover, co-contraction of both forearm flexor and extensor muscles is necessary to produce claw protrusion.The functional anatomy of claw retraction for felids differs considerably from that of most other carnivorans. However, the claw retractile mechanism for some advanced viverrids is structurally similar to that of the felids. For these viverrids prey seizing, as in the felids, has become a function of the forelimbs. For the other families of carnivorans, the jaws and not the forelimbs are used as the primary organ of prehension and the anatomy of the claw retractile mechanism reflects functional demands placed on it other than grasping and holding prey.

Notes: The gross relationships and light microscopic anatomy of the suprarenal gland of a prosimian primate, Galago senegalensis, is described. The left gland is located medial to the pole of the left kidney in a fascial compartment of its own. The right suprarenal is located medial to the pole of the right kidney in intimate apposition to the liver and inferior vena cava. The capsule of the right gland blends with the capsule of the right lobe of the liver and is also contiguous with the adventitia of the inferior vena cava.The histologic appearance of the gland is similar to that of other primate genera. The zona glomerulosa is poorly developed; the zona fasciculata is composed of cell cords and is relatively well developed and the zona reticularis shows no unusual characteristics. The organization of the lipid content of the various cortical zones show a considerably different pattern than previously reported. The zona glomerulosa contains numerous large lipid droplets. In contrast to the bi-laminar pattern of lipid deposition seen in other primates, the Galago shows three distinct layers of lipid droplets in the zona fasciculata. The zona reticularis has a moderate population of lipid droplets essentially similar to that reported in most other forms. The medulla, except for a sparse number of centrally displaced zona reticularis cells, is completely devoid of lipid deposits. The junction of the zona reticularis and medulla is distinct, although a connective tissue capsule is not present.

Notes: The projections of the accessory and main olfactory bulbs of the bullfrog are described as part of a long term analysis of the morphological differences in amphibian and reptilian telencephalons. Unilateral aspiration of the accessory olfactory bulb results in an ipsilateral projection to the pars lateralis of the amygdala via the accessory olfactory tract. Degenerating fibers from the accessory olfactory bulb are tracable into the cell-free zone between the dorsal striatum and the lateral pallium, and projections to these neural populations may also exist. Unilateral lesions of the main olfactory bulb reveal two major secondary pathways: an ipsilateral medial olfactory tract that projects to the rostral ventromedial portion of the medial pallium, the postolfactory eminence and the rostral, lateral and medial septal nuclei; and an ipsilateral lateral olfactory tract that projects to the dorsal striatum, the lateral pallium and the ventral half of the dorsal pallium. Two crossed secondary olfactory pathways to the contralateral telencephalon decussate via the habenular commissure after entering the ipsilateral stria medullaris. A crossed lateral pathway terminates in the dorsal striatum, the caudal, lateral pallium and the ventral portion of the dorsal pallium. A crossed medial pathway terminates in the internal granule layer of the main olfactory bulb.

Notes: The brook stickleback, Culaea inconstans (Kirtland), in common with other bony fishes, lacks a germinal epithelium in the tubules of the testis, and the tubule wall is composed of a thin, discontinuous layer of myoid cells and collagenous fibers. Labelling of germ cells with tritiated thymidine has shown that the germ cells are derived from clumps of spermatogonia in the interstitial area. Large companion cells within the lumina of the tubules extend their processes to engulf spermatogonia from the interstitium which then enter the lumen of the tubule. Subsequent development of the germ cells takes place within individual compartments formed by folds of the plasma membrane of a companion cell. The companion cell, together with its complement of germ cells, constitutes a cyst. A companion cell may surround spermatogonia in the interstitium and at the same time encompass residual sperm of the previous season within the lumen. The plasma membranes of the germ cells and the companion cells remain discrete. Mature sperm are released into the lumen of the tubule and the companion cell again extends its processes into the interstitium and engulfs more spermatogonia for the following year.Companion cells may be homologous to the Sertoli cells of higher vertebrates although their processes penetrate the interstitium during the initial stages of spermatogenesis and they do not contain a permanent stock of spermatogonia.

Notes: The cephalic clasper of the male Chimaera collei is a cartilaginous rod equipped with denticles and presumably used to grasp the female during copulation. It is attached to the skull by ligaments but there is no joint cavity or articular surface. It has no intrinsic muscles, its movements being provided by attachments to muscles of the lower jaw and labial cartilages. The cephalic clasper is apparently elevated by a branch of the preorbitalis muscle, whose main function is to elevate the lower jaw. It appears to be forcefully depressed during copulation by M. levator anguli oris, whose primary function is to move the labial cartilages. When not in use, the cephalic clasper is held passively depressed by an elastic tendon from M. preorbitalis. In the female the cephalic clasper is represented by an apparently functionless rudiment.

Notes: A new pattern index, Ip, is introduced and used to compare patterns of wild type, burnsi, and kandiyohi chromatophores in the leopard frog, Rana pipiens. Wild type chromatophores are hyperdispersed over distances within cellular contact, and it is concluded that this hyperdispersion results from contact-mediated negative interactions. The hyperdispersion is less strong in spot cells than interspot, and extends over larger areas in burnsi than in wild type epidermis. Over areas greater than chromatophore size, patterns are either random or clumped. Patterning of kandiyohi melanophores is clumped into aggregates small enough to be within the range of cellular contact, suggesting a lack of contact inhibition among these cells. The possible roles of cellular properties and the extracellular environment in pattern determination are discussed.

Notes: Interpretation of cross and tangential sections of the annulate lamellae and nuclear membrane of Rana pipiens oocytes provides evidence in these structures for the existence of diaphragms spanning the pores. The evidence appears to rule out explanations ascribing such diaphragms to an optical artifact. More detailed description is given of a component of the pore complex only briefly described heretofore and now called the “intracisternal ring.” The varied results and interpretations of studies of the pore complex in various cells are discussed.

Notes: The masticatory apparatus in the albino rat was studied by means of electromyography and subsequent estimation of muscular forces.The activity patterns of the trigeminal and suprahyoid musculature and the mandibular movements were recorded simultaneously during feeding. The relative forces of the individual muscles in the different stages of chewing cycles and biting were estimated on the basis of their physiological cross sections and their activity levels, as measured from integrated electromyograms. Workinglines and moment arms of these muscles were determined for different jaw positions.In the anteriorly directed masticatory grinding stroke the resultants of the muscle forces at each side are identical; they direct anteriorly, dorsally and slightly lingually and pass along the lateral side of the second molar. Almost the entire muscular resultant force is transmitted to the molars while the temporo-mandibular joint remains unloaded. A small transverse force, produced by the tense symphyseal cruciate ligaments balances the couple of muscle resultant and molar reaction force in the transverse plane. After each grinding stroke the mandible is repositioned for the next stroke by the overlapping actions of three muscle groups: the pterygoids and suprahyoids produce depression and forward shift, the suprahyoids and temporal backward shift and elevation of the mandible while the subsequent co-operation of the temporal and masseter causes final closure of the mouth and starting of the forward grinding movement. All muscles act in a bilaterally symmetrical fashion.The pterygoids contract more strongly, the masseter more weakly during biting than during chewing. The wide gape shifts the resultant of the muscle forces more vertically and more posteriorly. The joint then becomes strongly loaded because the reaction forces are applied far anteriorly on the incisors. The characteristic angle between the almost horizontal biting force and the surface of the food pellet indicates that the lower incisors produce a chisel-like action.Tooth structure reflects chewing and biting forces. The transverse molar lamellae lie about parallel to the chewing forces whereas perpendicular loading of the occlusal surfaces is achieved by their inclination in the transverse plane. The incisors are loaded approximately parallel to their longitudinal axis, placement that avoids bending forces during biting. It is suggested that a predominantly protrusive musculature favors the effective force transmission to the lower incisors, required for gnawing. By grinding food across transversely oriented molar ridges the protrusive components of the muscles would be utilized best. From the relative weights of the masticatory muscles and their topographical relations with joints, molars and incisors it may be concluded that the masticatory apparatus is a construction adapted to optimal transmission of force from muscles to teeth.

Notes: The description of stages of the molt cycle in mantis shrimp (emphasizing Gonodactylus but compared in a number of Gonodactylidae, Squillidae, and Lysiosquillidae) includes data on texture, hardness, and color of the exoskeleton; behavior; and the micromorphology of the integument and developing setae.After stage A1, When the exoskeleton feels soft and soapy, and A2, when the abdomen attains parchment consistency, the exoskeleton continues to harden until stage C1, when the telson carinae can no longer be depressed with a fingernail. The propodus (C2) and the merus (C3) of the raptorial appendage are the last elements to become rigid. The meral spot achieves indistinct coloration at B1 and distinct but pale coloration at B2; body color continues to intensify until C4.Changes in behavior are particularly marked before and after the molt. After the molt defensive and avoidance behaviors characterize A1 and A2. Threatening increases from low to intense levels in A2 and B1. Striking and offensive behavior increase from weak to normal intensities from B2 to C4. One or two days before the molt, animals lower activity and dominance and feeding levels, exhibit reclusive behavior, and sometimes seal the cavity entrance.The morphology of setagenesis is particularly valuable for determining the stage of the molt after the exoskeleton hardens. The ratio of setae containing cellular contents throughout the lumen to those condensed into strands separates stages A2 through C3. “Cones,” although variable within and between individuals in some species, form initially in B2 and continue to condense through D. Initiation of C4, D0 and D1 overlaps variously in some individuals. Apolysis (D0) and morphogenesis of new setae (D1-D3) provide cues for identifying approach of the molt. Setagenesis and setal morphology differ among families, genera and some species of stomatopods. The structure and functional morphology of setae can be explained by the form of setagenesis.Passive swelling and active muscular peristalsis effect the shedding of the exoskeleton and setal eversion at the molt. The carapace and rostrum are shed as one unit. Patterns of meral sutures vary among taxa with enlargement of the merus and with subterminal or terminal ischiomeral articulation. Middorsal sutures open only on the sixth and seventh thoracic segments, suggesting loss of the first rather than the last abdominal segment and therefore a distant relationship to other eumalacostracans.Approximate durations of the molt stages in stomatopods are compared to those of 11 crustacean taxa. Extensive overlap seems to occur among midinterval stages, particularly in stomatopods. The developmental plateau occurs in different stages in different taxa. Late postmolt (C), associated with calcification, requires longer in more heavily calcified than in thinly calcified species, except for stomatopods. The physiological events immediately surrounding the the molt (A1-B1 and D3-D4) are compressed in time in crayfish, brachyurans, and especially in stomatopods. Behavioral adaptations maximize this compression of physiological events at the molt in stomatopods. These three groups also possess the most asymmetrical molt cycles of the crustacean taxa examined. It is hypothesized that these modifications of the molt cycle allow opportunistic molting and represent adaptations to agonistic behavior.Temporal variation in behavior and in color over the molt cycle may increase the potential for speciation by processes resembling neoteny.

Notes: Pheromone systems from seven species of noctuid are examined. Much of the structure of scales from the wings and/or the abdomen is interpreted as a modification for secretion or release of a pheromone. Scales with an extremely complex surface provide a large evaporation surface, while those connected to secretory cells show less superficial folding than body-covering scales.The development of the secretory gland and diseminatory scales in Mamestra configurata is followed from the exuvial pharate adult stage to emergence. Both components are paired and develop from epidermal cells lining a pair of large lateral invaginations. They may have resulted through division of a group of less specialized cells that originally combined the function of pheromone production and release.

Notes: Examinations of stages of fibril development in muscle fibers of seven Rhesus monkey and six human fetuses reveal SR tubules encircling the Z lines at all stages of fibril development. The encircling SR tubules are continuous with the SR network of tubules which is found surrounding fibrils at all stages of development observed. The SR tubules encircling the Z lines show connections (electron-opaque strands) with the Z lines. The developing triadic junction shows a progressive increase in complexity of structures within the junction. First, membranes of T and SR become apposed with no visible structure between them. Second, tenuous connections are found traversing the space between apposed membranes. Third, well developed bridges are seen traversing the space. And finally, an intermediate density midway between the apposed membranes and parallel to them is found in favorable sections. Junctions between T tubule membranes were also observed and the structures in these junctions are somewhat similar to those found in junctions between T and SR membranes. The change in orientation of triads from predominantly longitudinal to predominantly transverse is complete in the 18-week monkey fetus and incomplete in the latest stage (28-week) of fetal development observed in humans.

Notes: Footfall patterns and time sequence of activity are described for white rats conditioned to run freely in an activity wheel (which they drive). Motion is described in terms of soft contact, hard contact, soft contact, and flip phases. Duration of stride decreases and length of stride increases from walk to trot to canter to gallop. Myographic analysis shows that the brachialis has a major tonic function after it fires strongly during the flip phase and during much of the hard contact phase. Animals running at canter or gallop show major asymmetries between forelimb muscles on the first paw and on the lead paw sides.

Notes: Fertilized golden hamster eggs were examined between 6 and 20 hours post-ovulation to determine the events leading to the two-cell stage. Following their migration the pronuclei remain in the central region of the zygote for approximately ten hours. The morphologically, indistinguishable male and female pronuclei remain relatively unchanged during this period, i.e., they do not interdigitate or fuse with one another as described for the zygotes of other organisms. Following this period and at the time of pronuclear breakdown elongate vesicles appear along the nucleoplasmic surface of the pronuclear envelopes. Later the pronuclear envelopes fragment into elongate cisternae; these and the vesicles formed along the inner lamina of the pronuclear envelopes remain closely associated and constitute quadrilaminar structures. The chromosomes which condense prior to and during pronuclear envelope breakdown, migrate to the equatorial plate of the forming cleavage spindle. After cytokinesis the chromosomes in the blastomere nuclei disperse. Increase in the nuclear envelope to accomodate this dispersion may involve the addition of membrane from the quadrilaminar structures.

Notes: Middle ears (515) from 26 species of the rodent family Heteromyidae  -  genera Dipodomys, Microdipodops, Perognathus, and Liomys  - were studied both grossly and histologically, for qualitative and quantitative comparisons. Middle ear modifications characteristic of each genus are qualitatively described. Quantitative comparisons are made among the 26 species in the study. Some correlations between middle ear size and other measurements are discussed.The middle ear is an acoustical transformer that for best efficiency must match the impedance of the cochlea to the impedance of the air in the external auditory meatus. It accomplishes this by a pressure increase and a velocity decrease through the combined effects of the lever and areal ratios; however, because the important consideration is a matching of two impedances rather than an absolute pressure increase, the pressure transformer ratio is a less informative measure of the middle ear's efficiency than is the impedance transform ratio. The impedance transformer mechanism is explained (from a morphological point of view), and equations are presented. Dipodomys, Microdipodops, and Perognathus have a theoretical transmission (at the resonant frequency) of 94-100% of the incident acoustical energy; Liomys, 78-80%. The areal ratio of stapes footplate to 2/3 tympanic membrane is remarkably constant among the species, varying only from 0.04 to 0.07: in Dipodomys and Microdipodops this small ratio is due to the very large tympanic membrane; in Perognathus and Liomys it is due to the extremely small stapes footplate. The lever ratio of incus to malleus varies from 0.28 to 0.33 in Dipodomys and Microdipodops, from 0.37 to 0.46 in Perognathus, and from 0.55 to 0.60 in Liomys. In addition, the middle ear volumes and the morphology of tympanic membrane, ossicles, ligaments, and muscles, all combine to minimize both mass and stiffness. All these data suggest middle ear mechanisms which are very efficient over a broad frequency range.The middle ear modifications found in heteromyids are adaptive in predator avoidance, especially in areas of little natural cover; nevertheless, contrary to expectations, there is no firm relationship between habitat and the extent of these modifications in the 26 species. However, environment did apparently play an important role in the evolution of the family, and this is discussed.

Notes: Ultrastructural changes were studied in the cells undergoing secretory differentiation in zone I of the tubules of the uropygial gland of White Plymouth Rock chickens. A layer of basal cells and four secretory stages are recognized as the cells migrate from the periphery to the lumen of tubules and progressively elaborate a secretion product.Basal cells, containing rough endoplasmic reticulum and free ribosomes, rest on the basement membrane and are the source from which secretory cells arise. Dilated perinuclear cisternae and the proliferation of smooth endoplasmic reticulum in the form of vesicles, invaginated sacs and cusp-shaped cisternae indicate the onset of lipogenesis in stage I cells. The perinuclear cisternae are more dilated and the endoplasmic reticulum is composed of saccules and cisternae in stage II cells. Stage III cells are characterized by concentric lamellae of endoplasmic reticulum surrounding secretory droplets. Dilated cisternae of endoplasmic reticulum and secretory droplets both contain a reticular substance. The perinuclear cisternae of stage III cells have returned to normal dimensions. Large mature lucent secretory droplets, lined with electron-dense material, fill the cytoplasm of stage IV cells which degenerate and release their secretory product into the tubule lumen.Spherical membrane-bound compartments containing a mottled substance of moderate electron density occur in basal cells and all subsequent secretory stages. These mottled bodies are surrounded by saccules of endoplasmic reticulum in stage II cells and are intimately associated with secretory droplets in stage III cells, but there is no evidence that they give rise to secretory droplets and their role in secretory differentiation is unknown.

Notes: The lateral ocelli of the dobsonfly (Protohermes grandis, Neuroptera) larva have been examined with light and electron microscopy. The larva has six ocelli on both sides of the head, each containing a single corneal lens. A conical crystalline body, of some 10-20 cells is situated immediately posterior to the lens. From 100 to 300 elongated retinular cells are arranged perpendicular to the crystalline body except at the innermost surface of the lens, where they are absent. The distal process of each retinular cell is enclosed by a tube-like rhabdom formed by the close association of microvilli from the same and adjacent distal processes. The distal process contains many mitochondria, multivesicular bodies, microtubles and pigment granules. In the dark-adapted ocellus the pigment granules are concentrated near the nucleus which lies under the rhabdomic layer. The granules diffuse toward the rhabdomic microvilli during light adaptation.Each retinular cell has a single axon, which extends from the ocellus as an ocellar nerve fiber into the optic lobe, where it frequently synapses upon second order neurons. In addition to these afferent synapses, there are two other synaptic combinations: (1) a feedback synapse from a second order neuron to a retinular axon, and (2) a synapse between second order neurons. These results suggest that photic signals reach the more proximal part of the brain via second order neurons after some degree of integration in the optic lobe.

Notes: Light and electron microscopic studies revealed ciliation of the epithelium of the entire gastro-intestinal tract of Polypterus. Acidophil cells were found in the different regions of the alimentary canal, including its derivatives (the lungs and hepato-pancreatic ducts). Compared to other primitive forms and modern teleosts, the extreme fusion of the intestinal caeca in Polypterus, the ciliation and the overall dispersion of acidophil cells may represent a special organization inherited from a palaeoniscoid ancestor. Attention is also drawn to a possible channel of early evolution and function of the stomach diverticulum.

Notes: Newly metamorphosed individuals of the Kenyan reed frog, Hyperolius viridiflavus ferniquei, are able completely to regenerate amputated digits, including the morphologically complex digital pad. The sequence of morphological events is very similar to that seen in the typical epimorphic regeneration of amphibian extremities. Amputated forearms typically produce hypomorphic spike regenerates. Despite the lack of underlying hand and digital structures, an apical “digital” pad commonly differentiates.

Notes: The functional and structural aspects of the suspensorium of Ctenopoma acutirostre have been correlated with those of Anabas testudineus. The different parts of the suspensorium are described, as are the muscles that are functionally connected with the suspensorium. Functions were analyzed by observations on living specimens, and by measurements recorded from the movie films. The role played by various bones and muscles to carry out the functions (the respiration, the gulping, and the feeding) has been explained. The different bones and muscles have been considered as functional units which often are connected to form couplings. During the respiration in Ctenopoma the depression of the lower jaw is conducted by the levator operculiopercular apparatus-mandible coupling. The presence of this coupling is indicated by the presence of dorso-ventral movement of the operculum. A remarkable ventro-dorsal and antero-caudal movement in the urhyal during feeding shows in Ctenopoma the presence of the sternohyoideus-hyoid apparatus-interopercular-mandible coupling, which depresses the lower jaw. In Ctenopoma, the suspensorium takes part in respiration, gulping, and feeding, whereas in Anabas it is only involved in gulping and feeding. To carry out its functions, the suspensorium implies three articulations: palatocranial, craniohyomandibular, and quadratomandibular with the cranium and the lower jaw, respectively. Finally, the suspensorium has been analyzed as a part of the architectonic structure of the entire head by using a diagrammatic model (fig. 13) based on mutual influence, integration, and couplings.

Notes: The effects of changing muscle length on the mechanical properties of 89 motor units from adult cat medial gastrocnemius have been studied in eight experiments.Few differences were found between the effects of length on tetanic tension, twitch tension, twitch-tetanus ratio, twitch contraction time, twitch half relaxation time, rate of force development and electrical activity for fast contracting (twitch contraction time ≤ 45 msec) and slowly contracting ( 〉 45 msec) units. Those differences that did appear did not persist when these two groups were matched by tetanic tension. It is concluded that the biophysical mechanisms responsible for the changes in mechanical and electrical properties with length must be similar for fast and slow twitch units and not related to potential differences in their muscle fiber type.The effects of changing muscle length on the mechanical properties of the eight whole muscles suggest that changes in force output with length are of minor importance during normal movements as the muscle is found to be electrically active over a relatively narrow range of lengths close to the optimum length for tetanus of the whole muscle. The very shortest muscle lengths at which there is only minimal force development are not used in natural movements, while the declining limb of the length tension curve is at muscle lengths beyond the maximum in situ length.

Notes: The antennae of the sawyer beetles Monochamus notatus and M. scutellatus were examined with the light and scanning electron microscopes to determine the types, number, distribution and innervation of the sense organs. Nine types of sensilla are described. Both short, thin-walled pegs (sensilla basiconica) and reversely curved thick-walled hairs (sensilla trichodea) are chemoreceptors. There are three types of long, thick-walled hairs (sensilla chaetica) which may be mechanoreceptors. One of these is modified in males to form unique snail-shaped pegs. A few dome-shaped organs, probably campaniform sensilla, were found.In addition to sense organs, many glands occur in association with the sensilla, and the antennae are well supplied with dermal glands connected by canals to small pores on the surface.

Notes: Prepartum embryos obtained from old museum specimens of the ovo-viviparous fish, Oligopus longhursti, possess external intestinal appendages. They are structurally identical to the trophotaeniae described by Turner ('37) and Mendoza ('37) in goodeid fishes. This is the first report of trophotaeniae in the viviparous ophidioids. Two developmental Stages, A and B, were observed. A is a tailbud stage, 2.0-2.25 mm in length, and B is a finfold embryo, 3.0-3.25 mm in length (Wourms and Bayne, '73). Trophotaeniae occur in the form of a single median anterior process and a pair of median posterior processes. They originate from a conspicuous peduncle formed around the anus. The processes of stage A are 1.5-2.0 mm long, 0.05 mm in diameter at their base and 0.04 mm at their tip. The stage B processes are 2.75-3.00 mm long, 0.075 mm in diameter at their base and 0.050 mm at their tip. Serial sections show that the surface epithelium of the trophotaeniae is continuous with and identical to the surface epithelium of the trophotaeniae is continuous with and identical to the surface epithelium of the embryonic gut. Examination both by transmission and scanning electron microscopy confirms that the apical surface of the trophotaenial epithelium and intestinal epithelium are covered with microvilli. Trophotaeniae are considered to function in the uptake of nutrients since they are structurally identical to intestinal epithelial cells. We suggest that maternal nutrients absorbed by trophotaeniae rather than yolk reserves are the principal source of embryonic metabolites. Trophotaeniae may afford a selective advantage since their existence in O. longhursti maximizes the number of large size embryos which a female can produce at one time. Occurrence of trophotaeniae in ophidioid, goodeid and zoarcid embryos is a remarkable example of convergent evolution.

Notes: The structure and evolution of the mandible, suspensorium, and stapes of mammal-like reptiles and early mammals are examined in an attempt to determine how, why, and when in phylogeny the precursors of the mammalian tympanic bone, malleus, and incus (postdentary jaw elements and quadrate) came to function in the reception of air-borne sound. The following conclusions are reached.It is possible that at no stage in mammalian phylogeny was there a middle ear similar to that of “typical” living reptiles, with a postquadrate tympanic membrane contacted by an extrastapes. The squamosal sulcus of cynodonts and other therapsids, usually thought to have housed a long external acoustic meatus, possibly held a depressor mandibulae muscle.In therapsids an air-filled chamber (recessus mandibularis of Westoll) extended deep to the reflected lamina and into the depression (external fossa) on the outer aspect of the angular element. A similar chamber was present in sphenacodontids but pterygoideus musculature occupied the small external fossa. The thin tissues superficial to the recessus mandibularis served as eardrum. Primitively, vibrations reached the stapes mainly via the anterior hyoid cornu, but in dicynodonts therocephalians, and cynodonts, vibrations passed mainly or exclusively from mandible to quadrate to stapes and the reflected lamina was a component of the eardrum.In the therapsid phase of mammalian phylogeny, auditory adaptation was an important aspect of jaw evolution. Auditory efficiency, and sensitivity to higher sound frequencies, were enhanced by diminution and loosening of the postdentary elements and quadrate, along with transference of musculature from postdentary elements to the dentary. These changes were made possible by associated modifications, including posterior expansion of the dentary. Establishment of a dentray-squamosal articulation permitted continuation of these trends, leading to the definitive mammalian condition, with no major change in auditory mechanism except that in most mammals (not monotremes) the angular, as tympanic, eventually became a non-vibrating structure.

Notes: The striations and the intervening filaments observed in the present study have been variously designated in the literature as: prodromal pattern, leptomeric myofibril, microladder, leptomeric organelle, leptofibril and zebra body. Electron microscope examinations of Purkinje fibers from the septa, papillaries, trabeculae carneae and small endocardial strands from chicken, sheep, dog and monkey hearts have revealed a close association between densely stained striations of supernumerary Z line material and successive parallel tubules in the network formed by the sarcoplasmic reticulum (SR). The striations appear to be linked together by filaments that somewhat resemble the part of thin filaments attached to Z lines in normal fibrils. The evidence for a close association of striations and SR tubules is derived from a similarity of spacing between striations and successive parallel tubules in the SR network and from a resemblance of striation and SR network patterns. The evidence for a structural relationship between striations and SR tubules is derived from the observation of electron-opaque strands traversing the space between striations and SR tubules.

Notes: The fine structure of oocytes of Urechis caupo is described for seven arbitrary stages ranging from the smallest oocytes (7μm in diameter) in the coelom to the mature oocytes (115 μm in diameter) in the storage organs. Although most types of cytoplasmic organelles accumulate more or less continuously, yolk granules do not appear until oocytes reach a diameter of 35 μm, and there is stage-specific synthesis of cortical granules in 60-80 μm oocytes. In the nucleus a single nucleolus first appears when an oocyte is 15 μm in diameter. Then a nucleolus satellite, which is about 3 μm in diameter, forms in 30 μm oocytes; this nucleolus satellite later (60-70 μm oocytes) becomes surrounded by 750 nm dense spherical bodies. Large (2-4 μm in diameter) juxtachromosomal spherules occur only in the nuclei of mature oocytes. Microvilli become progressively more numerous and longer until the oocytes reaches a diameter of 90 μm their tips project 1 μm beyond the fibrous surface coat, which is 2 μm thick when well developed. Near the end of oocyte growth, the microvilli retract into the surface coat leaving their pinched-off tips adhering to the outside of the coat.

Notes: The authors describe the synthesis of decahydro-4-quinolinones and N-substituted 4-alkynyl-, 4-allyl- and 4-alkyldecahydro-4-quinolinols and discuss the stereochemical problems of this compounds.