PURPACTINS, NEW INHIBITORS OF ACYL-COA - CHOLESTEROL ACYLTRANSFERASE PRODUCED BY PENICILLIUM-PURPUROGENUM .2. STRUCTURE ELUCIDATION OF PURPACTIN-A, PURPACTIN-B AND PURPACTIN-C

The structure of purpactins, novel acyl-CoA:cholesterol acyltransferase (ACAT) inhibitors, was determined by spectroscopic analyses. Purpactin A was deduced to be 3-1'-acetoxy-11-hydroxy-4-methoxy-9-methyl-3'-methylbutyl-5H,7H-dibenzo[b,g]-1,5-dioxocin-5-one, purpactin B was 5-1"-acetoxy-6'-hydroxymethyl-4-methoxy-4'-methyl-3"-methylbutyl-spiro[benzofuran-2,1'-cyclohexa-3',5'-diene]-2',3(2H)-dione and purpactin C was 5-1"-acetoxy-6'-formyl-4-methoxy-4'-methyl-3"-methylbutyl-spiro[benzofuran-2,1'-cyclohexa-3',5'-diene]-2',3(2H)-dione. Purpactin A was attributed to 1'-O-acetylpenicillide.