Potentially active hypoglycemic agents from N1-nicotinoyl-2-pyrazolin-5-one derivatives and their N1-(oxynicotinoyl) analogues.

Several ethyl 2,3-dioxohexanoate 2-arylhydrazone derivatives were obtained via coupling of the appropriate diazonium chlorides with ethyl butanoylacetate. Acetic acid-mediated cyclization of these products with N1-nicotinoyl and/or N1-(oxynicotinoyl)hydrazine derivatives gave a new series of 4-arylhydrazono-3-(n-propyl)-N1-nicotinoyl-2-pyrazolin-5-one s (Va-h) as well as their N1-(oxynicotinoyl) analogues (VIa-h). The structure of the prepared compounds was confirmed on the basis of elemental and spectral data. The hypoglycemic effect, antibacterial activity and toxicity of these agents were evaluated and discussed.