Anicequol, a novel inhibitor for anchorage-independent growth of tumor cells from Penicillium aurantiogriseum Dierckx TP-F0213

A novel inhibitor for anchorage-independent growth of tumor cells was isolated from the culture broth of a Fungal strain. The producing strain TP-F0213 was identified as Penicillium aurantiogriseum Dierckx based on the taxonomic study. The compound designated anicequol was obtained by solvent extraction, HP-20 and silica gel chromatographies and recrystallization. The planar structure was elucidated by NMR analysis to be 16-acetoxy-3,7,11-trihydroxyergost-22-en-6-one. The absolute configuration was determined by the X-ray analysis of 3,7-bis-p-bromobenzoyl derivative. The carbon skeleton of anicequol has the same absolute configuration as ergostane and the configurations of substituents are 3beta, 5alpha, 7beta, 11beta, 16beta and 24S. Anicequol inhibited the anchorage-independent growth of human colon Cancer DLD-1 cells with the IC50 of 1.2 microM whereas the IC50 against anchorage-dependent growth was 40 microM.