Synthetic studies on d-biotin, part 9.1) An improved asymmetric synthetic route to d-biotin via Hoffmann-Roche lactone-thiolactone approach

Abstract

An efficient and highly stereoselective total synthesis of d-biotin has been achieved starting from cis-1,3-dibenzyl-2-imidazolidone-4,5-dicarboxylic acid (2) with an overall yield of 33%. Polymer-supported oxazaborolidine- catalyzed asymmetric reduction of meso-cyclic imide 4 constitutes the key synthetic step in introducing stereogenic centers into the d-biotin molecule. © 2005 Pharmaceutical Society of Japan.