alpha-Amido sulfones from natural ?-amino acids and their reaction with carbon nucleophiles

Amides obtained from N-carbamoyl ?-amino acids react with aldehydes in the presence of benzenesulfinic acid to give ?-amido sulfones in good yield. These derivatives act as equivalents of N-acylimines in the reaction with nucleophiles leading to the corresponding addition products. The utilization of the lithium enolate of alkyl acetates as a nucleophile allows the preparation of ?,?-dipeptides, while a two-step procedure involving nitromethylation and Nef conversion leads to the synthesis of ?,?-dipeptides. © 2005 Elsevier Ltd. All rights reserved.