The transformation and resolution of 8-aza steroids by fungi.

1. When (+/-)-8-aza-d-homo-oestrone 3-methyl ether was added to a culture of Aspergillus ochraceus, the laevo-rotatory enantiomer is reduced to a 17A alcohol. Thus (+/-)-8-aza-d-homo-oestrone 3-methyl ether has been resolved into both its components, the laevo-rotatory enantiomer being obtained by chromic acid oxidation of the alcohol, and the dextro-rotatory enantiomer as residual precursor from the fermentation. 2. Fungi have been found to demethylate the 3-methyl ethers of 8-aza steroids to the corresponding phenols. In particular, 8-aza-d-homo-oestrone 3-methyl ether was demethylated by Aspergillus flavus and 8-aza-d-homo-oestradiol 3-methyl ether by Cunninghamella blakesleeana.