4-(4-Amino-6,7-dimethoxy-2-quinazolinyl)-1-piperazinecarboxaldehyde Hydrochloride (Terazosin EP Impurity D) is a pyrimidine derivative and a useful synthetic intermediate. Pyrimidine derivatives such as 4-amino-2-(4-cinnamoylpiperazino)-6,7-dimethoxyquinazol can be developed into antihypertensive agents.
