FUNCTIONALIZATION AT C-12 IN LABDANIC DITERPENES: SYNTHESIS OF THE NATURAL DITERPENIC LACTONES ISOLATED FROM CISTUS LADANIFERUS L.

Article abstract of DOI:10.1016/S0040-4039(01)80929-1

Oxidative cyclization of Labdanediol (XII) and methyl Labdanolate (Ib) with Pb(OAc)4, and subsequent oxidation with reagents as RuO4, O3, CrO3 or (tBu)2CrO4 affords, in excellent yield, the natural diterpenic lactones II, III, VII, VIII, XI and XIII, isolated from Cistus ladaniferus L.