There are disclosed benzothiadiazinyl and quinazolinyl substituted carboxylalkyl dipeptides, wherein the benzothiodiazinyl or quinazolinyl portions are joined to the dipeptide portions by an aminocarbonyl group. Compounds of this invention are useful as antihypertensive agents, in the treatment of congestive heart failure and in the treatment of glaucoma. In addition, compounds of this invention have diuretic activity.