Enantiospecific synthesis of (+)-puupehenone from (-)-sclareol and protocatechualdehyde

Article abstract of DOI:10.1016/S0040-4039(97)00305-5

The first enantiospecific synthesis of the antitumor and cholesteryl ester transfer protein (CETP) inhibitor (+)-puupehenone (19) from (-)-sclareol (10) and protocatechualdehyde (4) is described. The key steps of the reaction sequence are the organoselenium-induced cyclization of the mixture of regioisomers 15a-b to give 16 and 17, with complete diastereoselectivity, and the simultaneous removal of benzyl and phenylselenyl groups of 16 and 17 by treating with Raney Ni.