1
|
Chiroptical properties of (+)- and (−)-2,6-dimethyl-1-nitrosopiperidine in connection with the sector rule for N
-nitrosoamines. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19730920206] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
2
|
|
3
|
Ripperger H. Räumliche Struktur der Moleküle und chiroptische Eigenschaften - neuere Ergebnisse. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/zfch.19770170703] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
4
|
Hesse S, Suhm MA. Conformation and Aggregation of Proline Esters and Their Aromatic Homologs: Pyramidal vs. Planar RR´N-H in Hydrogen Bonds. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2009.6043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The conformations of proline esters are investigated by infrared spectroscopy in supersonic slit jet expansions. Two easily convertible puckering variants of the pyrrolidine ring with intramolecular N-H···O contacts are shown to be particularly stable. The aggregation tendency of proline esters via intermolecular N-H···O hydrogen bonds is remarkably weak. IR differences between enantiopure and racemic dimers are difficult to quantify. Dehydrogenation of the pyrrolidine ring to pyrrole leads to a stable planar carboxylic ester conformation. Its aggregation tendency is pronounced due to the planar hybridization of the nitrogen atom and leads to a symmetric, β sheet-like dimer with strongly red-shifting hydrogen bonds. The spectroscopic observations underscore the differences between intermolecular interactions of N-terminal and peptide-bound amino acids in peptide chains.
Collapse
|
5
|
Chapter 2 Solanum Steroid Alkaloids. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/s1876-0813(08)60132-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/23/2023]
|
6
|
Gaffield W, Lundin RE, Keeper LK. Chiroptical properties of n-nitrosopyrrolidines and n-nitrosamino acids. Tetrahedron 1981. [DOI: 10.1016/s0040-4020(01)97934-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
7
|
Ferber S, Richardson F. Molecular orbital studies on the optical activity of chiral nitrosamines and nitramines. Tetrahedron 1977. [DOI: 10.1016/0040-4020(77)80222-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
8
|
Z-E conformational dependence of the N-nitrosamine circular dichroism. The need of revision of the nitrosamine sector rule. Tetrahedron Lett 1976. [DOI: 10.1016/s0040-4039(00)78079-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
9
|
|
10
|
Ringdahl B, Dahlbom R. Chiroptical properties of n-nitroso-2-methylpyrrolidine in relationship to the nitrosamine sector rule. Tetrahedron Lett 1976. [DOI: 10.1016/s0040-4039(00)93038-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
11
|
|
12
|
|