作者:Robert L. Broadrup、Bei Wang、William P. Malachowski
DOI:10.1016/j.tet.2005.08.029
日期:2005.10
A selection of azapeptidomimetics containing constraining lactam rings have been prepared by Mitsunobu cyclization of serine/ homologated serine-azaalanine derivatives. These include sterically-congested beta-lactams, as well as gamma-butyrolactam and delta-valerolactam analogs. A novel azaamino acid acylation method was developed to prepare the sterically demanding alpha-benzyl-serine-azaalanine precursor. In all cases, the Mitsunobu conditions were highly efficient in forming the desired azapeptidomimetic lactams. The reported process represents a general strategy for the synthesis of peptidomimetic structures with a constraining lactam ring. (c) 2005 Elsevier Ltd. All rights reserved.