Microbiological hydroxylation of steroids. Part V. The pattern of hydroxylation of dioxygenated 5α-androstanes with cultures of the fungus Calonectria decora
Dioxygenated 5α-androstanes are more readily hydroxylated with Calonectria decora than the mono-oxygenated substrates studied previously. Oxygen functions in rings A and D act as primary directing groups and, when a blocking effect by middle ring substituents is allowed for, the pattern of hydroxylation is predictable in most cases.
1β-Hydroxy-compounds are obtained in moderate yields from the readily accessible 5α-androstane-6,17- and 7,17-diones.