A NOVEL ONE-STEP SYNTHESIS OF PYRANO[3,2-C]QUINOLINES AND A TRANSFORMATION INTO 3,3-BIS-(4-HYDROXY-2-QUINOLONE)ARYL-METHANES

4-Hydroxy-2-quinolone (1) reacts with cinnamonitrile derivatives 2a-f and 5a, b in presence of catalytic amounts of triethylamine to afford pyrano[3,2-c]quinolines 4a-h and 6a, b. The reaction of 4a with reagen ts such as acetic anhydride/pyridine, formamide and formic acid/formam ide gave the fused heterotetracyclic system of the typ of pyrimido[4', 5':6,5]pyrano[3,2-c]quinoline. Ring transformation of the pyrano[3,2-c ]quinolines 4a-e led to 3,3'-Bis-(4-hydroxy-quinoline-2-one)aryl-metha nes 14a-c.