Reaction of o -Formylbenzoic Acid with Hydrazides of (Iso)niconitic and Hydroxybenzoic Acids

The reaction of nicotinic and isonicotinic acid hydrazides with o -formyl benzoic acid in ethanol led to the formation of the corresponding hydrazones. It was found that o -formyl benzoic acid reacted in aldehyde form with hydrazides to form hydrazones. When heated in acetic anhydride, the latter are smoothly cyclized into 3-acetoxyisoindolin-1-ones. Structure of the synthesized compounds was proved by 1 H and 13 C NMR spectroscopy data. Antiradical and antiviral activity of the synthesized hydrazones and 3-acetoxyisoindolin-1-ones was studied. A compound with a wide spectrum of virus-inhibiting action against strains of the A virus was identified.