Alpha-glucosidase and tyrosinase inhibitors from fungal hydroxylation of tibolone and hydroxytibolones
作者:M. Iqbal Choudhary、S. Adnan Ali Shah、Atta-ur-Rahman、Shamsun-Nahar Khan、Mahmud Tareq Hassan Khan
DOI:10.1016/j.steroids.2010.05.017
日期:2010.12
Sixteen new and one known metabolites 4-20 were obtained by incubation of tibolone (1) and hydroxytibolones (2 and 3) with various fungi. Their structures were elucidated by means of a homo and heteronuclear 2D NMR and by HREI-MS techniques. The relative stereochemistry was deduced by 2D NOESY experiment. Metabolites of tibolone (1) exhibited significant inhibitory activities against alpha-glucosidase and tyrosinase enzymes. Hydroxylations at C-6, C-10, C-11, C-15 positions and alpha,beta-unsaturation at C-1/C-2, C-4/C-5 showed potent inhibitory activities against these enzymes. (C) 2010 Elsevier Inc. All rights reserved.