Synthetic studies of 1-β-methylcarbapenem antibiotics

Abstract

The diastereoselective synthesis of the 1-β-methylcarbapenems, (1R,5R,6S)-6-((R)-1-hydroxyethyl)-2-((S)-1-acetimidoylpyrrolidin-3-ylthio)-1-methyl-1-carbapen-2-em-3-carboxylic acid and sodium (1R,5R,6S-6-((R)-1-hydroxyethyl)-2-(5-chloro-2-oxobenzoxazolm-3-yl)-lmethyl-1-carbapen-2-em-3-carboxylate has been achieved. The key step was an aldol reaction between the achiral boron enolate which was generated from dibutylboron triflate and 3-propionyl-2-oxobenzoxazoline, and (3R,4R)-4-acetoxy-3-((R)-1-hydroxyethyl)azetizin-2-one. © 1989, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.