Benazepril hydrochloride. Molecular model of the drug benazepril hydrochloride (C24.H28.N2.O5?HCl). This is an ACE inhibitor used primarily in treatment of hypertension, congestive heart failure, and heart attacks, and also in preventing the renal and retinal complications of diabetes. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue), oxygen (red) and chlorine (green).