Biosynthesis of verrucarol, the sesquiterpene moiety of the verrucarins and roridins

Incorporation experiments with (3R)-[5-14C]-mevalonate and both enantiomers of [2-3H]mevalonate into verrucarin A and roridin A indicate that hydroxylation at C-4 of verrucarol proceeds with retention of configuration; they confirm that C-8 and not C–10 is derived specifically from C-2 of mevalonate, and that the pro-2-S hydrogen of mevalonate is lost during the biosynthesis of verrucarinolactone.