abstract |
Pharmaceutical compositions which have steroid C17,20 lyase inhibiting activity and are useful as preventive or therapeutic agents for prostatism o r tumors such as breast cancer, more particularly, steroid C17,20 lyase inhibitors characterized by containing a compound of the general formula (I) or a salt or prodrug thereof, wherein A1 is an optionally substituted aromat ic hydrocarbon group or an optionally substituted heterocyclic group; and one o f A2 or A3 is hydrogen, halogeno, an optionally substituted C1-4 aliphatic hydrocarbon group, or optionally esterified carboxyl, and the other is an optionally substituted heterocyclic group, with the proviso that at least on e of A1, A2, and A3 is optionally substituted 3-pyridyl. |