SYNTHESIS OF [1-C-14] NORDOLICHOIC ACID

We describe the synthesis of nordolichoic acid and [1-C-14]nordolichoi c acid starting from polyprenol isolated from the leaves of Ginkgo bil oba. Coupling of polyprenol with ethyl acetoacetate, using ,1'-(azodic arbonyl)dipiperidine/tributylphosphine, followed by hydrolysis, decarb oxylation and reduction, yielded the 2-polyprenyl-1-methylethanol. Thi s alcohol was converted into a mesylate, subjected to one-carbon elong ation with KCN, and finally converted to the acid by hydrolysis of the nitrile.