Electrochemical oxidation of proline derivatives: total syntheses of bulgecinine and bulgecin C
作者:Anthony G. M. Barrett、Daniel Pilipauskas
DOI:10.1021/jo00008a040
日期:1991.4
The influence of structure on the efficiency of the electrochemical C-5 oxidation of (2S,4S)-hydroxyproline carbamate esters is presented. Optimum methoxylation was observed with (2S,4S)-4-acetoxy-1,2-pyrrolidine-dicarboxylic acid 2-methyl 1-(2-(trimethylsily)ethyl) ester (19). The corresponding C-5 methoxy derivative 20 was converted into bulgecinine (4) via a stereospecific radical homologation to incorporate the C-5 hydroxymethyl substituent. Bulgecin C (1c) was prepared via a beta-stereoselective glycosidation reaction using a 2-azido-2-deoxy-alpha-D-glucopyranosyl trichloroacetimidate derivative, regiospecific C-4' sulfation, and deprotection.
Total syntheses of bulgecinine and bulgecin C from (2S,4R)-hydroxyproline
作者:Anthony G. M. Barrett、Daniel Pilipauskas
DOI:10.1021/jo00305a007
日期:1990.8
Structures of bulgecins, bacterial metabolites with bulge-inducing activity