Quinazoline derivatives and their preparation

摘要

A compound of the formula: <IMAGE> in which R1 and R2 are each hydrogen, halogen, nitro, amino, protected amino, hydroxyamino, lower alkyl, hydroxy, protected hydroxy, sulfamoyl, carboxy, protected carboxy, mercapto, optionally substituted heterocyclic-carbonyl, optionally substituted heterocyclic-(lower)alkyl, lower alkylthio, hydroxy(lower)alkyl or protected hydroxy(lower)alkyl, R3 is aryl which may have suitable substituent(s), and A is lower alkylene, or pharmaceutically acceptable salts thereof.