Synthesis of threo-3-methyl-d-cysteine, a moiety of β-methyllanthionine as a component of the peptide antibiotics nisin and subtilin, was achieved via (2R,3R)-1-t-butoxycarbonyl-3-methyl-2-aziridinecarboxamide derived from d-threonine. An addition of thioacetic acid or thiobenzoic acid to the aziridinecarboxamide gave S-acyl-β-mercapto-α-amino acid amide derivatives which were hydrolyzed directly or after the preformation of disulfide bond to afford the desired amino acid.
The synthesis of optically active 2H-azirine-2-carboxylicesters was achieved by Swern oxidation of the corresponding aziridine-carboxylic esters. For both trans and cis aziridine esters this oxidation gives a regioselective introduction of the double bond which is not in conjugation with the ester function. The methyl ester of ent-Azirinomycin was prepared in this manner.
cis-Selective aziridination of cis- or trans-α,β-unsaturated amides using diaziridine
作者:Kiyoto Hori、Hiroyasu Sugihar、Yoshio N. Ito、Tsutomu Katsuki
DOI:10.1016/s0040-4039(99)00939-9
日期:1999.7
Aziridination of alpha,beta-unsaturated amides was effected by treatment with lithiated 3,3-pentamethylenediaziridine in high diastereoselectivity. cis-Aziridine was the predominant diastereomer irrespective of the geometry of the substrates. A stepwise mechanism, 1,4-addition of a lithiated diaziridine to alpha,beta-unsaturated amides and subsequent ring closure at the nitrogen atom was proposed to explain the unusual cis-selectivity. (C) 1999 Elsevier Science Ltd. All rights reserved.