Biosynthesis of cyclolaudenol in Polypodium vulgare Linn

Abstract
Alkylation of a phytosterol precursor to give cyclolaudenol and 31-norcyclolaudenol involves retention of a hydrogen atom at C-24, elimination of a proton from the terminal methyl group arising from C-3′ of mevalonic acid, and probable retention of all three hydrogen atoms of the incoming methyl group of methionine.