Abstract:
In this work, biotransformations of dehydroepiandrosterone (DHEA) 1 by Ulocladium chartarum MRC 72584, Cladosporium sphaerospermum MRC 70266 and Cladosporium cladosporioides MRC 70282 have been reported. U. chartarum MRC 72584 mainly hydroxylated 1 at C-7 alpha and C-7 beta, accompanied by a minor hydroxylation at C-4 beta, a minor epoxidation from the beta-face and a minor oxidation at C-7 subsequent to its hydroxylations. 3 beta,7 beta-Dihydroxy-5 beta,6 beta-epoxyandrostan-17-one 6, 3 beta,4 beta,7 alpha-trihydroxyandrost-5-en-17-one 7 and 3 beta,4 beta,7 beta-trihydroxyandrost-5-en-17-one 8 from this incubation were identified as new metabolites. C. sphaerospermum MRC 70266 converted some of 1 into a 3-keto-4-ene steroid and then hydroxylated at C-6 alpha, C-6 beta and C-7 alpha, accompanied a minor 5 alpha-reduction and a minor oxidation at C-6 following its hydroxylations. C. sphaerospermum MRC 70266 also hydroxylated some of 1 at C-7 alpha and C-7 beta. C. cladosporioides MRC 70282 converted almost half of 1 into a 3-keto-4-ene steroid and then hydroxylated at C-6 alpha and C-6 beta. C. cladosporioides MRC 70282 also reduced some of 1 at C-17.