The Condensation of Cyclic Anhydrides with Schiff Bases. A Convenient Synthesis of 1,4,6-Triaryl-5-carboxy-2-oxo-1,2-dihydropyridines and 2,3-Diaryl-4-carboxy-1-oxo-1,2-dihydroisoquinolines - Mayadeo, M S; Kulkarni, S J; Deodhar, K D (Synthesis, 1990)