Premium
Conformation changes induced in 2‐spiro‐substituted cephalosporin sulphoxides by the configuration of the spiro bond: A combined 1 H and 13 C NMR study
Author(s) -
ErdödinéKövér Katalin,
Jászberényi J. Cs.
Publication year - 1984
Publication title -
organic magnetic resonance
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0030-4921
DOI - 10.1002/mrc.1270220906
Subject(s) - diazomethane , chemistry , stereochemistry , nuclear magnetic resonance spectroscopy , cephalosporin , computational chemistry , nitrogen , crystallography , medicinal chemistry , organic chemistry , biochemistry , antibiotics
1,3‐Dipolar cycloadditions of diazomethane and diphenyldiazomethane to exo ‐2‐methylenecephalosporins are described. A structural study of the products shows that the initially formed 2‐spiropyrazolinocephems form cyclopropanes by the spontaneous loss of nitrogen. ASIS and NOE measurements reveal that the products with different C‐2 configurations are in two different conformations.