Determination of theerythro andthreo configuration of the two diastereoisomeric 2-amino-3-mercaptobutyric acids by NMR spectroscopy of derived thiazolidines
作者:S. Toppet、P. Claes、J. Hoogmartens
DOI:10.1002/mrc.1270060113
日期:1974.1
AbstractA study of the 1H and 13C NMR spectra of the N‐formyl‐2,2,5‐trimethyl‐4‐carboxythiazolidines and the N‐formyl‐4‐carboxy‐5‐methylthiazolidines derived from the two diastereoisomeric 2‐amino‐3‐mercapto‐DL‐butyric acids, permits unambiguous assignment of the erythro and threo configuration of these amino acids. The spectra of the N‐formylthiazolidines, recorded in DMSO‐d6 solution, reveal the presence of two conformational isomers with a low rate of interconversion. The geometry around the carbon–nitrogen bond and correlated conformations of the 5‐membered ring in both forms are discussed.