ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Synthese und Konfiguration einiger Spiro [indan-2,2′-pyrrolidin]- und Spiro [pyrrolidin-2,2′-tetralin]-DerivateTeilweise vorgetragen an der Herbstversammlung der Schweizerischen Chemischen Gesellschaft in Bern, 8.10.1977.,Herrn Professor André S. Dreiding zum 60. Geburtstag gewidmet (1979)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 62 (1979), S. 1223-1230 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and configuration of some spiro [indan-2,2′-pyrrolidine] and spiro [pyrrolidine-2,2′-tetraline] derivativesCatalytic hydrogenation of the nitrosoindan and nitrosotetralin derivatives 8 yielded trans-1-hydroxy-spiro [indan-2,2′-pyrrolidin]-5′-one (9) and trans-1′-hydroxy-spiro [pyrrolidine-2,2′-tetralin]-5-one (10) respectively, whilst the corresponding cis compounds 12 and 15 were prepared via the chlorides 11 and 14.The configurations of 10 and 13 were determined by X-Ray analysis.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19790620433
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Peptide conformations. Part 31Part 30: [1a].. The conformation of cyclosporin a in the crystal and in solution (1985)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 68 (1985), S. 682-704 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The all-light-atom X-ray crystal-structure analysis of cyclosporin A (1), a cyclic undecapeptide containing seven N-methylated amino acids, reveals a conformation very similar to that of the previously analysed iodo derivative which is characterised by a twisted β-pleated sheet involving the residues Me-Val-11, MeBmt-1, Abu-2, Sar-3, MeLeu-4, Val-5, MeLeu-6, and Ala-7. The β-bend at Sar-MeLeu-4 is of type II′, and the loop of the residual amino acids involves a cis-peptide bond between MeLeu-9 and MeLeu-10. The NH proton of D-Ala-8 closes a yi-bend with a H-bond to the MeLeu-6 CO group. The crystal was grown from acetone. A closely similar backbone conformation in apolar solvents such as CDCl3 or C6D6 has been derived from the interpretation of the NMR spectral parameters (homo- and heteronuclear NOE effects, coupling constants, chemical-shift values of the C-, H-, and N-atoms). A minor variation in the backbone conformation between crystal and solution is observed in the region of D-Ala-8, where in solution a 3-center H-bond is established between the NH of D-Ala-8 und the carbonyl O-atoms of both MeLeu-6 (yi-turn) and D-Ala-8 (C5-bend). A recently proposed technique to identify intramolecular H-bond via heteronuclear NOE from NH proton to carbonyl C-atoms is critically analysed. The main difference between crystal and solution conformations lies in the orientation of the side chains of the unusual amino acid MeBmt (χ1 = +60° in solution, -168° in the crystal) and of MeLeu-10 (X1 = -60° in solution, +60° in the crystal). The differences in crystal and solution are caused by the break of the intermolecular H-bond of the OH group of MeBmt on dissolution of the crystal. The bifurcated H-bond of D-Ala-8 twists the backbone in this region. Molecular modeling demonstrates that this is the origin of the change in the side chain conformation of MeLeu-10. The intramolecular flexibility in the crystal indicated by the thermal parameters obtained from the X-ray refinement, and in solution by an analysis of spin-lattice relaxation times in the NMR experiments, indicate a fairly rigid backbone and fixed conformations for all the side chains except for that of Abu-2 and the distal atoms of MeBmt.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19850680319
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Desoxy-nitrozucker. 2. Mitteilung Herstellung geschützter 1-Desoxy-1-nitroaldosen (1982)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 65 (1982), S. 621-634 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of Protected 1-Deoxy-1-nitroaldosesThe direct oxidation of the oxime 1 with t-butyl hydroperoxide and vanadyl acetylacetonate yielding the nitro derivative 2 (54%, Scheme 1) could not be applied to other oximes. Diastereoselective bromination of the aldonolactone oxims 7 and 10-12 according to known procedures gave the corresponding bromonitroso compounds which were oxidized to the bromonitro compounds 9, 14, 18 and 22, respectively. Oxidation of the bromonitroso compound in the D-mannopyranose series proved difficult, but the corresponding chloronitro derivative 23 was easily obtained according to Corey & Estreicher (Scheme 2 and 3). The structure of the bromonitro compound 9 was determined by an X-ray analysis, and the configurations of the bromonitro compounds 14, 18 and 22 were deduced from their molecular rotations. Reduction of the bromonitro compounds gave the protected 1-deoxy-l-nitroaldoses 2, 15/16, 19/20, and 24/25, respectively, in good overall yields. The ribose derivatives 15 and 16 were detritylated to give the nitro compound 4, and the mannose derivative 2 was partially deprotected to give the monoisopropylidene compound 26. The nitro group shows a normal anomeric effect which is reflected in the IR. spectra of the pyranose derivatives 19 and 20, and 24 and 25.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19820650302
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Unexpected Hydroxyspirolactone Formation upon Baeyer-Villiger Oxidation of a trans-α-decalone (trans-octahydronaphthalen-1(2H)-one) and X-ray structure of the product (1995)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 78 (1995), S. 887-890 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: trans-4,4,10-Trimethyl-9-decalone ( = trans-5,5,8a-trimethyl-octahydronaphthalen-1(2H)-one; 1), when treated with trifluoroperacetic acid, gave the unexpected hydroxyspirolactone 7-hydroxy-7,11,11-trimethyl-1-oxaspiro[5.5]undecan-2-one (6), in which the two new O-atoms were introduced in a 1,2-trans relationship. The structure of this compound was conclusively proven by X-ray crystallography. The process involves the intermediacy of 7-membered lactone 2, the expected Baeyer-Villiger product, which could also be successfully prepared under controlled conditions at 0° in a buffered medium containing Na2HPO4.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19950780411
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Acetale von 1,2,3,4-Tetraoxobutan: Herstellung und Struktur von rac- und meso-2,3,3,4,4,5-Hexamethoxy-tetrahydrofuranZum ehrenden Andenken an Herrn Professor Dr. Dr. h.c. Hans Schmid, der am 24.3.77 seinen 60. Geburtstag gefeiert hätte (1977)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 60 (1977), S. 410-416 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Acetals of 1,2,3,4-tetraoxobutane: preparation and structure determination of rac- and meso-2,3,3,4,4,5-hexamethoxy-tetrahydrofuranOxidation of 3,4-dimethoxyfuran with 2 equiv. of bromine at -75° in the presence of triethylamine and methanol leads to a mixture of rac- and meso-2,3,3,4,4,5-hexamethoxy-tetrahydrofuran (cf. Scheme 1, 4 and 5). The structure of the crystalline rac-compound has been determined by X-ray analysis.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19770600212
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Absolute Configuration of 3-Substituted 1-Azabicyclo[2.2.1]heptanesDedicated to Professor Dr. Vladimir Prelog on the occasion of his 85th birthday (1992)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 75 (1992), S. 507-512 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The l-azabicyclo[2.2.1]heptan-3-exo-ol (2) was resolved by fractional crystallisation of its hydrogen tartrate salts. The enantiomers (+)- and (-)-2 were oxidised to the ketones (-)-4 and (+)-4, respectively (Scheme). CD spectroscopy suggested that (-)-4 possesses the (1R,4S)-configuration. This absolute configuration was confirmed by single-crystal X-ray diffraction of the derivative (+)-(1R,4R)-3-(1,3-dithian-2-ylidene)-1-azabicyclo [2.2.1]-heptane ((+)-5).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19920750210
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Ringöffnung von N-(Tetraalkylamidinio)pyridinium-Salzen durch Anionen methylenaktiver Verbindungen (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 3276-3296 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ring Opening of N-(Tetraalkylamidinio)pyridinium Salts by Anions of CH-Acidic Methylene CompoundsN-Carbeniopyridinium salts 2, 4, 14, and 18 offer three sites to nucleophilic attack; depending on the reactants, all three modes have been realized. With anions of CH-acidic methylene compounds, α-attack at the pyridinium ring followed by ring opening leads to azahexamethine merocyanines (8, 15, 23). In some cases, kinetically controlled reactions yield 1,4-dihydropyridines which isomerize thermally to give 1,2-dihydropyridines which undergo ring opening spontaneously. Also, nucleophilic attack at the cationic substituent of the N-carbeniopyridinium salts is possible as is indicated by the formation of push-pull olefins 11, 16 and of enol ether 12.
    Notes: Die N-Carbeniopyridinium-Salze 2, 4, 14 und 18 bieten für den Angriff eines Nucleophils drei Möglichkeiten, die sich in Abhängigkeit von den Reaktionspartnern alle realisieren lassen. Mit Anionen methylenaktiver Verbindungen führt der α-Angriff am Pyridinium-Ring unter Ringöffnung zu Azahexamethinneutrocyaninen (8, 15, 23). In einigen Fällen bilden sich kinetisch kontrolliert 1,4-Dihydropyridine, die sich thermisch zu den 1,2-Dihydro-pyridinen bzw. deren ringgeöffneten Folgeprodukten umlagern. Schließlich ist auch der nucleophile Angriff am kationischen Substituenten der N-Carbeniopyridinium-Salze möglich, wie die Bildung der Push-pull-Olefine 11, 16 und des Enolethers 12 zeigt.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861191109
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Azahexamethin-Neutrocyanine mit einem Diaminocyclopropenyliden-Auxochrom (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1791-1794 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Azahexamethine Neutrocyanines with a Diaminocyclopropenylidene AuxochromeBy ring opening of the N-(2,3-diaminocyclopropenylio)pyridinium salt 1 with the anions of malononitrile, dimedone, or Meldrum's acid the protonated polymethines 5a-c are formed, which yield the neutral dyestuffs 6a-c on deprotonation. In solution, 5a, b are transformed slowly into the triafulvenes 3a, b. Analogously, polymethine 10 is obtained from the diaminochlorocyclopropenylium salt 8, pyridine, and malononitrile, although the equilibrium of formation of the presumed intermediary pyridinium salt 9 lies far on the side of the components.
    Notes: Durch Ringöffnung des N-(2,3-Diaminocyclopropenylio)pyridinium-Salzes 1 mit den Anionen von Malononitril, Dimedon oder Meldrums Säure entstehen die protonierten Polymethine 5a-c, die sich zu den neutralen Farbstoffen 6a-c deprotonieren lassen. In Lösung entstehen aus 5a, b langsam die Triafulvene 3a, b. Aus dem Diaminochlorcyclopropenylium-Salz 8, Pyridin und Malononitril bildet sich analog das Polymethin 10, obwohl das intermediär anzunehmende Pyridinium-Salz 9 in Lösung nur in einem weit auf die Seite seiner Komponenten verschobenen Gleichgewicht vorhanden ist.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881211015
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Homoisoflavanones. V. Crystal and Molecular Structure of (-)-7-O,-(p-Bromophenacyl)-eucomol. The Absolute Configuration of (-)-EucomolThe position of the hydroxyl group and methoxy hydrogen atoms were taken from a difference electron density map. (1977)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 60 (1977), S. 1388-1392 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Homoisoflavanone. V. Kristalline und molekulare Struktur von (-)-7-O,-(p-Bromphenacyl)-eucomol. Absolute Konfiguration von (-)-EucomolZur Abklärung der absoluten Konfiguration von (-)-Eucomol wurde eine Röntgenstrukturanalyse des 7-O-p-Bromphenacylderivates durchgeführt. Auf Grund der anomalen Streuung von CuKα-Strahlung durch Brom liess sich 3S-Chiralität der Verbindung nachweisen. Die durch 372 Atomparameter beschriebene Struktur wurde mit 1745 Strukturfaktoren bis zu R = 0,071 verfeinert.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19770600429
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The Crystal and Molecular Structure of HydroxybenzylpindololTrivial name for 1-(1-p-hydroxyphenyl-2-methyl-2-propylamino)-3-(4-indoloxy)-2-propanol. (1977)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 60 (1977), S. 1398-1402 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kristalline und molekulare Struktur von HydroxybenzylpindololIm Zusammenhang mit einer Studie über die Konformation von adrenergen β-Blockern wurde die kristalline Struktur von Hydroxybenzylpindolol durch Röntgen-analyse bestimmt. Die Kristalle sind triklin, Raumgruppe P1, a = 10,041(2), b = 11,386(2), c = 10,131(2) Å, α = 114,03(2), β = 107,82(3), γ = 99,32(3)°, mit zwei Molekeln pro Zelle. Die Struktur wurde nach dem «Multisolution»-Prinzip gelöst und bis zu R=0,050 verfeinert. Die Molekeln sind im Kristall durch ein Netz von Wassertoffbrücken miteinander verbunden.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19770600431
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...