Design and Synthesis of Tricyclic Derivatives as High Density Lipoprotein Cholesterol Enhancers. -The synthesis and evaluation of imidazoisoquinolones [cf. (Va), (Vb)], related pyrimidoisoquinolones [cf. (VII)], and imidazonaphthyridines [cf. (Vc)] as high density lipoprotein cholesterol enhancing compounds is described. The synthetic route involves a novel and widely applicable one-step preparation of 3-carboxamidophthalides (III) from 2-acylbenzoic acids (I). -(ELOKDAH, HASSAN; CHAI, SIE-YEARL; HO,