SUBSTITUTED THIAZOLE DERIVATIVES BEARING 3-PYRIDYL GROUPS, PROCESS FOR PREPARING THE SAME AND USE THEREOF

摘要

The present invention provides a pharmaceutical composition having a steroid C17,20-lyase inhibitory activity, which is useful as a prophylactic or therapeutic agent of prostatism, tumor such as breast cancer and the like, more particularly, a steroid C17,20-lyase inhibitor containing a compound represented by the formula: <CHEM> wherein A<1> is an aromatic hydrocarbon group optionally having substituents or a heterocyclic group optionally having substituents, one of A<2> and A<3> is a hydrogen atom, a halogen atom, a C1-4 aliphatic hydrocarbon group optionally having substituents or an optionally esterified carboxyl group, the other of A<2> and A<3> is an aromatic hydrocarbon group optionally having substituents or a heterocyclic group optionally having substituents, and at least one of A<1>, A<2> and A<3> is a 3-pyridyl group optionally having substituents, or a salt thereof or a prodrug thereof.