Indexed on: 10 Mar '17Published on: 16 Feb '17Published in: Journal of Molecular Catalysis B: Enzymatic
The regioselective oxidation of three lathyrane diterpenoids (lathyrol, 1; 7β-hydroxylathyrol, 2; and Euphorbia factor L3, 3) catalyzed by the fungi Mortierella ramanniana CGMCC 3.03413, Mucor circinelloides CICC 40242, and the actinomycete Nocardia iowensis sp. nov. NRRL 5646 was investigated. Ten new metabolites (4–13) including two unprecedented cyclopropane-rearranged products (4 and 5) have been obtained. Metabolites (6, 10 and 11) were further converted chemically to eight acylated derivatives (6a, 10a–10f and 11a). The structures of all compounds were elucidated on the basis of extensive NMR and MS data analyses. All the metabolites and enzyme-chemical products were evaluated for their cytotoxicities against three human cancer cell lines as well as their multidrug resistance (MDR) reversing effects in adriamycin (ADM)-resistant human MCF-7 breast cancer cells (MCF-7/ADM).