Chemistry of the Ginkgolides. Part 10: Access to 14C-Labelled Ginkgolide A

In four reaction steps, ginkgolide A (1) was synthesized from the enol-acetate 3, which is available in six steps from 1. The key step was the reaction of the α-epoxy-acetate 4 with the lithium enolate of methyl propionate to give the compounds 5 and 6. 14C-Labelled ginkgolide A, which is of interest for pharmacological studies, can be synthesized using the 14C-labelled methyl propionate.