Application of alpha- and beta-naphthoflavones as monooxygenase inhibitors of Absidia coerulea KCh 93, Syncephalastrum racemosum KCh 105 and Chaetomium sp KCh 6651 in transformation of 17 alpha-methyltestosterone

In this work, 17 alpha-methyltestosterone was effectively hydroxylated by Absidia coerulea KCh 93, Syncephalastrum racemosum KCh 105 and Chaetomium sp. KCh 6651. A. coerulea KCh 93 afforded 6 beta-, 12 beta-, 7 alpha-, 11 alpha-, 15 alpha-hydroxy derivatives with 44%, 29%, 6%, 5% and 9% yields, respectively. S. racemosum KCh 105 afforded 7 alpha-, 15 alpha-and 11 alpha-hydroxy derivatives with yields of 45%, 19% and 17%, respectively. Chaetomium sp. KCh 6651 afforded 15 alpha-, 11 alpha-, 7a-, 6 beta-, 9 alpha-, 14 alpha-hydroxy and 6 beta, 14 alpha-dihydroxy derivatives with yields of 31%, 20%, 16%, 7%, 5%, 7% and 4%, respectively. 14 alpha-Hydroxy and 6 beta, 14 alpha-dihydroxy derivatives were determined as new compounds. Effect of various sources of nitrogen and carbon in the media on biotransformations were tested, however did not affect the degree of substrate conversion or the composition of the products formed. The addition of alpha-or beta-naphthoflavones inhibited 17 alpha-methyltestosterone hydroxylation but did not change the percentage composition of the resulting products. (C) 2018 Elsevier Inc. All rights reserved.