Atropisomerism in azadipeptides: evaluation of N1-methylation and thioamide introduction
摘要:
Cbz-protected azadipeptides, designed as structurally reduced model compounds, were synthesized and investigated with respect to the occurrence of atropisomerism. Methylation at the carbamate nitrogen caused mixtures of E and Z isomers in Cbz-sarcosyl-azaglycine-amide (9) and Cbz-sarcosyl-methylazaala-nine-amide (10). A formal O/S exchange led to Cbz-glycyl-azaglycine-thioamide (11) and Cbz-glycyl-methylazaalanine-thioamide (12), respectively. The (MeN)(2) fragment, present in 10 and 12 (but not 9 and 11), serves as a chirality-inducing element owing to a restricted rotation around the N-N axis. (C) 2015 Elsevier Ltd. All rights reserved.
Induction of chirality: experimental evidence of atropisomerism in azapeptides
作者:Philipp A. Ottersbach、Gregor Schnakenburg、Michael Gütschow
DOI:10.1039/c2cc31161e
日期:——
Methylation of the peptide bond in model azadipeptides leads to the E configuration and hence to atropisomerism due to a restricted rotation around the N–N axis.