Carotenoids and related polyenes. Part 7.1 Total synthesis of crassostreaxanthin B applying the stereoselective rearrangement of tetrasubstituted epoxidesWe have employed the numbering system used in carotenoids.

Abstract

3R,3ЈS )-and (3R,3ЈR)-Crassostreaxanthin B isomers are synthesized by application of the stereoselective rearrangement of tetrasubstituted epoxides 5a,b. As a result, the absolute configuration at C-3Ј of 1 is determined to be S.