Chemistry of substituted quinolinones. III. Synthesis and reactions of some novel 3-pyrazolyl-2-quinolinones

The preparation of 4-hydroxy-1-methyl-3-(5-oxo-4,5-dihydro-1H-3-pyrazolyl)- 1,2-dihydro-2-quinolinone (3) and its hydrazono-, aminomethylidene- and ary lidene derivatives has been achieved. The synthesis of fused heterocyclic p olynuclear systems containing quinolinone moiety is also described. Quinolinones are an important class of heterocyclic therapeutic agents. Man y 4-hydroxy-1,2-dihydro-2-quinolinones have a wide spectrum of pharmacologi cal applications. For example, different quinolinones. revealed anti-tumor, (l) anti-HSV,(2) anti-convulsion,(3) anti-oxidation and anti-inflammatory a ctivity(4) and bactericidal, fungicidal and molluscicidal activity.(5) Also , some pyrazoloquinolinones. showed potent biological activity.(6)