Preparation process of ginkgolide B from ginkgolide C

摘要

A two-step process for converting ginkgolide C into ginkgolide B is disclosed. In the first step, ginkgolide C is reacted with a sulfonic anhydride to obtain a C-7 sulfonate of ginkgolide C. In the second step, the C-7 sulfonate of ginkgolide C is reacted with a borohydride, and this reaction eliminates the C-7 radical of the C-7 sulfonate of ginkgolide C, thus producing ginkgolide B.