Stereoselective partial synthesis of (+)-pisiferic acid

Article abstract of DOI:10.1002/hlca.19950780404

(±)-Pisiferic acid (1), an antibiotic active against Gram-negative and Gram-positive bacteria, was synthesized starting from dehydroabietic acid (2) or abietic acid (26). The terpene ring system was functionalized and a Barton reaction used to oxidize Me(20). The intermediates of this photochemical reaction were isolated and characterized.