Abstract
The fungal transformations of ethynodiol diacetate (1) were investigated for the first-time using Botrytis cinerea, Trichothecium roseum, and R3-2 SP 17. The me-tabolites obtained are as following: 17 alpha-Ethynyl-17 beta-acetoxyestr-4-en-3-one-15 beta-ol (2), 19-nor-17a-ethynyltestosterone (3), and 17 alpha-ethynyl-3 beta-hydroxy-17 beta-acetoxyestr-4-ene (4). The new metabolite, 2 (IC50 = 104.8 mu M), which has ketone group at C-3, and the beta-hydroxyl group at C-15, resulted in an almost equipotent strength with the parent compound (IC50 = 103.3 mu M) against proliferation of SH-SY5Y cells. The previously reported biotransformed product, 3, showed almost equal strength to 1 against acetylcholinesterase. Molecular modelling studies were carried out to understand the observed experimental activities, and also to obtain more information on the binding mode and the interactions between the biotransformed products, and enzyme.