A new synthetic access to bicyclic polyhydroxylated alkaloid analogues from pyranosides
作者:Ning Wang、Li-He Zhang、Xin-Shan Ye
DOI:10.1039/b923180c
日期:——
A facile, versatile and stereoselective synthesis of bicyclic polyhydroxylated alkaloids as castanospermineanalogues is described. The synthetic route started from methyl pyranosides. The key steps involved a high-yielding expeditious one-pot tandem reaction from alkenes to N-substituted δ-lactams. The δ-lactams were stereoselectively vinylated to give the dienes, which were followed by the ring-closing
Efficient synthesis of (+)-1,8,8a-tri-epi-swainsonine, (+)-1,2-di-epi-lentiginosine, (+)-9a-epi-homocastanospermine and (−)-9-deoxy-9a-epi-homocastanospermine from a d-glucose-derived aziridine carboxylate, and study of their glycosidase inhibitory activities
作者:K. S. Ajish Kumar、Vinod D. Chaudhari、Dilip D. Dhavale
DOI:10.1039/b712753g
日期:——
The utility of a D-glucose-derived aziridine carboxylate was demonstrated for the synthesis of polyhydroxylated quinolizidine and indolizidine alkaloids. The chemoselective reduction of 1 followed by two-carbon homologation by the Wittig reaction afforded gamma,delta-aziridino-alpha,beta-unsaturated ester 9, which on regioselective nucleophilic aziridine ring opening either by using water as a nucleophile