Biocatalytic modifications of ethynodiol diacetate by fungi, anti-proliferative activity, and acetylcholineterase inhibitory of its transformed products

•The fungal transformations of ethynodiol diacetate (1) were investigated for the first time using Botrytis cinerea, Trichotheciumroseum, and R3-2 SP 17.•The metabolites obtained are as following: 17α-Ethynyl-17β-acetoxyestr-4-en-3-one-15β-ol (2), 19-nor-17a-ethynyltestosterone (3), and 17α-ethynyl-3β-hydroxy-17β-acetoxyestr-4-ene (4).•Ethynodiol diacetate (1) along with its biotransformed metabolites were subjected to anti-proliferative activity against SH-SY5Y cells and anti-acetylcholinesterase activity.•The new metabolite, 2 (IC50 = 104.8 µM), in an almost equipotent strength with the parent compound (IC50 = 103.3 µM) against proliferation of SH-SY5Y cells.•This is further supported by the binding mechanism of 1,and 3 into the structure of rhAChE, which were examined through molecular docking studies.•The activities reported here are good illustrations in supporting the application of microbial transformation as a viable method of future development of drug candidates. The fungal transformations of ethynodiol diacetate (1) were investigated for the first-time using Botrytis cinerea, Trichothecium roseum, and R3-2 SP 17. The metabolites obtained are as following: 17α-Ethynyl-17β-acetoxyestr-4-en-3-one-15β-ol (2), 19-nor-17a-ethynyltestosterone (3), and 17α-ethynyl-3β-hydroxy-17β-acetoxyestr-4-ene (4). The new metabolite, 2 (IC50 = 104.8 µM), which has ketone group at C-3, and the β-hydroxyl group at C-15, resulted in an almost equipotent strength with the parent compound (IC50 = 103.3 µM) 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.