GB953486A - Process for the microbiological oxidation of steroids - Google Patents

Abstract

11-Unsubstituted D 4-3, 20-dioxo-16a -alkyl-pregnene compounds are 11b -hydroxylated by the action of enzymes from fungi of the species Mucor griseocyanus. The starting steroid preferably has the formula: <FORM:0953486/C2/1> (wherein X is chlorine or fluorine, R1 is hydrogen or halogen and R2 is a free or functionally converted hydroxyl group) or is a corresponding 1, 2-dehydro compound, although general reference is also made to starting materials containing free or functionally converted hydroxyl, oxo or carboxyl groups, more especially hydroxyl groups in positions 17 or 21, halogen atoms, particularly at position 6, and hydrocarbon residues, such as methyl groups at positions 1, 2 or 6. As functional derivatives, reference is made to ethers, esters, ketals, enol ethers, enol esters, enamines, hydrazones, oximes and semicarbazones. Reference is also made to oxo and carboxyl groups at position 18. The process is effected under aerobic conditions with a growing culture of the mould, either in a surface culture or submersed, e.g. the deep-tank method. Alternatively the active enzymes are isolated from the growing culture before use. An example is given.