4-AZa-steroid compounds are provided, Wh1Ch have func
tional groups at one or more of positions 7, 11 and 15, such
as hydroXyl or hydroXyl derivative groups. The compounds
are active against S-ot-reductase giving indications of utility
in combating prostate cancer. The compounds can be pre
pared by chemo-enZymatic synthesis from easily available
4-aZa-steroids.