A compound having the structurewherein R is an angiotensin receptor antagonist active group, and Y isY is selected from the group consisting ofR1 is selected from the group consisting of—O—C1-6 alkyl,—O-aryl,—O-heteroaryl,—O—C3-8 cycloalkyl,—C1-6 alkyl,-aryl,-heteroaryl, and—C3-8 cycloalkyl;R2 and R3 are independently selected from the group consisting of hydrogen and C1-4 alkyl, or a pharmaceutically acceptable salt or hydrate thereof, which is useful for treating hypertension.