PYRIPYROPENES, NOVEL INHIBITORS OF ACYL-COA - CHOLESTEROL ACYLTRANSFERASE PRODUCED BY ASPERGILLUS-FUMIGATUS .1. PRODUCTION, ISOLATION, AND BIOLOGICAL PROPERTIES

Aspergillus fumigatus FO-1289, a soil isolate, was found to produce a series of novel inhibitors of acyl-CoA: cholesterol acyltansferase (AC AT). Four active compounds, named pyripyropenes A, B, C and D, were is olated from the fermentation broth of the producing strain by solvent extraction, silica gel column chromatography, ODS column chromatograph y and preparative HPLC. Pyripyropenes A, B, C and D show very potent A CAT inhibitory activity in an enzyme assay system using rat liver micr osomes with IC50 values of 58, 117, 53 and 268 nM, respectively.