ENANTIOSPECIFIC SYNTHESIS OF TRISUBSTITUTED BUTYROLACTONE NATURAL-PRODUCTS AND THEIR ANALOGS

A general methodology for the synthesis of highly substituted butyrola ctones in enantiomerically pure form has been developed. The applicati on of this process in a highly efficient synthesis of lactone natural products blastmycinone (1), NFX-S (2), antimycinone (3), and NFX-4 (4) and two lipid metabolites (5, 6) are described. Additionally, the tot al synthesis of 5-epi-blastmycinone (22), 5-epi-NFX-2 (21b), 5-epi-NFX -4 (21c), and lipid metabolite analogs (19, 20) are also described. Th e overall yields for the target molecules are the highest reported so far in the literature.