Library

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
    Ringschlüsse von Pyruvoylpeptiden und Dehydropeptiden Über Aminosäuren und Peptide, XXIV; Über Dehydroaminosäuren, XI (1978)
    Springer
    Monatshefte für Chemie 109 (1978), S. 147-155 
    Details
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Further studies were made of the influence of structure on the ring closure reactionsA andB of pyruvoyl peptides and dehydropeptides. Pyruvoyl peptides can undergo aldol condensation (3 a-c) as an alternative to cyclization. Pyruvoyl tetrapeptide amides and dehydroalanyl tetrapeptide amides were synthesized. Formation of larger rings by insertion of an amide-NH into pyruvoyl carbonyl or the double bond of the dehydro amino acid respectively could not be detected.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00911954
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Photochemische Abspaltung von atomarem Schwefel aus Isothiocyanaten (1978)
    Springer
    Monatshefte für Chemie 109 (1978), S. 161-164 
    Details
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Reaction rate, efficiency and back reaction of the photolysis of isothiocyanates yielding isonitriles and sulfur have been investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00911956
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Notiz zur Synthese des Nonactins (1975)
    Springer
    Monatshefte für Chemie 106 (1975), S. 1043-1044 
    Details
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract With (−)-nonactic acid and the 8-epitosylate of benzyl (+)-nonactate usingWalden inversion (−)-nonactyl-(+)-nonactic acid is constructed. The latter forms by way of its imidazolide or its α-mercaptopyridyl ester the macrotetrolide nonactine in poor yield.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00900883
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Notiz zur Synthese des optisch aktiven (—)-(2R,3R,6S,8S)-Nonactinsäure-methylesters (1975)
    Springer
    Monatshefte für Chemie 106 (1975), S. 219-222 
    Details
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Using optically active propylene oxide (from lactic acid) methyl (−)-nonactate is prepared by way2→3→4→5→6→1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00914515
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Cis-Cycloprolylprolin-Anion-ein konfigurationsstabiles Carbanion (1975)
    Springer
    Monatshefte für Chemie 106 (1975), S. 313-320 
    Details
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The racemisation ofcyclo-(l-Pro−l-Pro) (2) with metal amides in liq. ammonia was examined. The K-kation causes more extensive racemisation than Na-kation, which in turn is more effective than Li+. This, the racemisation of2 int-butyl alcohol with K+C6H5O− and the data gained from corresponding deuterated medium show that the racemisation of2 proceeds in two steps: in the first, the less stabletrans-cyclo-(l-Pro−d-Pro) (3) is formed, followed by the rapid conversion of3 to a mixture ofcyclo-(l-Pro−l-Pro) andcyclo-(d-Pro−d-Pro) in the second step.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00914523
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Lichtreaktionen mit Carbonsäurederivaten, IX. Abfangversuche mit photochemisch erzeugtem monoatomarem und diatomarem Schwefel. Schwefeladdition an 1,2-Dimethylencyclohexan. - Synthese von 1,4,5,6,7,8-Hexahydrobenzo[d][1,2]dithiin und 1,3,4,5,6,7-Hexahydrobenzo[c]thiophen (1975)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 630-639 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Photoreactions with Carbonic Acid Derivatives, IX. Experiments on the Capture of Photochemically Produced Monoatomic and diatomic sulfur-Sulfur Addition on 1,2-Dimethylenecyclohexane.-Synthesis of 1,4,5,6,7,8-Hexahydrobenzo-[d][1,2]dithiin and 1,3,5,6,7-Hexahydrobenzo[c]thiopheneIn addition to cis- and trans-2,3-diethoxy-2-butene (3) small amounts of 2,3-diethoxy-1-butene (6), 2,3-diethoxy-1,3-butadiene (7) and 1-ethoxy-1-ethanethiol (5) were found in the irradiation product of O-ethyl thioacetate. The produced sulfur adds to a slight extent to 1,2-Dimethylenecyclohexane giving 1,4,5,6,7,8-hexahydrobenzo[d][1,2]dithiin (8), 1,3,4,5,6,7-hexahydrobenzo-[c]thiophene (9) and 4,5,6,7-tetrahydrobenzo[c]thiophene (10). For definite identification of the reaction products 8, 9 and 10 were synthesized.
    Notes: Im Bestrahlungsprodukt von Thionessigsäure-äthylester (1) wurden neben cis- und trans-2,3-Diäthoxy-2-buten (3) in geringen Mengen noch 2,3-Diäthoxy-1-buten (6); 2,3-Diäthoxy-1,3-butadien (7) und α-Mercaptodiäthyläther (5) nachgewiesen. - Der gebildete Schwefel addiert sich in geringem Ausmaß an 1,2-Dimethylencyclohexan unter Bildung von 1,4,5,6,7,8-Hexahydrobenzo[d][1,2]dithiin (8), 1,3,4,5,6,7-Hexahydrobenzo[c]thiophen (9) und 4,5,6,7-Tetrahydrobenzo[c]thiophen (10). Zur sicheren Identifizierung der Reaktionsprodukte wurden 8, 9 und 10 synthetisiert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19751080229
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Über Aminosäuren und Peptide, XV. Hydroxylsubstituierte Cyclodipeptide durch Ringschluß von Pyruvoylaminosäureamiden, II Zweifacher Ringschluß (1975)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 2907-2916 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Amino Acids and Peptides, XV. Formation of hydroxycyclodipeptides by Cyclization of Pyruvoyl Amino Acids, II. Double Cyclization2-Oxo-5-(pyruvoylamino)valeric methylamide (15) is synthesized via the compounds 10-14. 15 is stable in cristalline form and in chloroform solution, but affords the dihydroxycyclodipeptide 16 in dilute HCl solution by a double cyclization reaction. Further reaction with H2S/ZnCl2 and subsequent dehydrogenation yield the epidithio-cyclodipeptide 17. 1,2-Dehydroproline methylamide (23) is obtained by reaction of 5-azido-2-oxovaleric methylamide (22) with triphenylphosphine.
    Notes: 2-Oxo-5-(pyruvoylamino)valerian-methylamid (15) wird über die Stufen 10-14 aufgebaut. 15, in kristallinem Zustand und in Chloroformlösung stabil, bildet in verdünnter Chlorwasserstoffsäure durch zweifachen Ringschluß das Dihydroxy-cyclodipeptid 16. Reaktion mit H2S/ZnCl2 und folgende Dehydrierung führen von 16 zur Epidithioverbindung 17. 5-Azido2-oxovalerian-methylamid (22) wird mit Hilfe von Triphenylphosphin in 1,2-Dehydroprolinmethylamid (23) umgewandelt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19751080910
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Über Aminosäuren und Peptide, XVI. Über Dehydroaminosäuren, III. Additionen an α-Iminocarbonsäuren (1975)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 2917-2922 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Amino Acids and Peptides, XVI. On Dehydroamino Acids, III. Addition Reaction to α-iminocarboxylic AcidsAddition reactions to dehydroproline methyl ester (1) and dehydroproline methylamide (2) are described as examples for additions to α-iminocarboxylic acid derivatives. The addition products of carbonylchlorides (e. g. 6 and 7) are synthetically important as they allow to synthesize α-alkoxy-α-acylaminocarboxylic acids (10), α-acetylthio-α-acylaminocarboxylic acids (11), and α-acylamino-α,β-dehydrocarboxylic acids (12 and 13). The addition products of α-substituted carbonyl chlorides such as α-bromopropionyl chloride and pyruvoyl chloride to dehydroproline compounds (e. g. 14 and 17) lead to cyclodipeptides with α-alkoxy and α-mercapto functions (15, 16, 18, 19).
    Notes: Als Beispiele für Anlagerungsreaktionen an α-Iminocarbonsäurederivate werden Additionsreaktionen an Dehydroprolin-methylester (1) und Dehydroprolin-methylamid (2) beschrieben. Synthetisch wertvoll sind die Anlagerungsprodukte von Carbonsäurechloriden (z. B. 6 und 7), von denen Wege zu α-Alkoxy-α-acylaminocarbonsäuren (10), α-Acetylthio-α-acylaminocarbonsäuren (11) und α-Acylamino-α,β-dehydrocarbonsäuren (12 und 13) führen. Die Additionsprodukte α-substituierter Carbonsäurechloride wie α-Brompropionylchlorid und Pyruvoylchlorid an die Dehydroprolinverbindungen (z. B. 14 und 17) führen zu Cyclodipeptiden mit α-Alkoxy- und α-Mercaptofunktionen (15, 16, 18, 19).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19751080911
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Über Aminosäuren und Peptide, XVII. über Dehydroaminosäuren, IV. Ringschlüsse an Dehydropeptiden (1977)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 921-941 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Amino Acids and Peptides, XVII. On Dehydroamino Acids, IV. Ring Closure of DehydropeptidesSix- or five-membered cyclic compounds (amino-piperazinediones: 2, 14-19, 21, 24, or imidazolidinones 28, 29) are obtained under basic conditions from dehydropeptides by α-addition of an amide function to the acylaminoacrylic unit. Sterical conditions, scope, and limitations of this cyclisation have been investigated up to the dehydrotetrapeptide amide 20. Formation of six-membered rings is preferred. Five-membered rings only result, if reaction to six-membered rings is excluded either by the structure of the dehydropeptide (no NH-function available) or by its conformation (s-trans amide function). Ring closure to the cyclodipeptides 2a, 14, 15, 18, 19, 21, and 24 proceeds stereoselectively.
    Notes: Dehydropeptide bilden in alkalischer Lösung durch α-Addition einer Amidgruppe an das Acylaminoacrylsäuresystem sechs- oder fünfgliedrige Ringe (Amino-piperazindione: 2, 14-19, 21, 24 bzw. Imidazolidinone: 28, 29). Reaktionsbedingungen, räumlicher Ablauf und Grenzen der Cyclisierung wurden bis zum Ringschluß des Dehydrotetrapeptidamids 20 untersucht. Der Sechsring wird bevorzugt. Ein Fünfring bildet sich nur dann, wenn die Cycloaddition zum Sechsring infolge der Struktur (keine NH-Funktion zur Addition) oder der Konformation (s-trans-Fixierung einer Amidbindung) des Dehydropeptids nicht möglich ist. Der Ringschluß zu den Cyclodipeptiden 2a, 14, 15, 18, 19, 21 und 24 verläuft stereoselektiv.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19771100312
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Bemerkungen zur „Three-step Synthesis of a Gliotoxin Analogue⃛“ von H. C. J. Ottenheijm et al. (1977)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 3722-3723 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19771101128
    Library Location Call Number Volume/Issue/Year 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...