Synthesis of functionally substituted esters of nicotinic and isonicotinic acid

Abstract

Nicotinic (3-pyridinecarboxylic) acid is one of the most important vitamins as well as substance with versatile physiological activity, since it plays significant role in the human organism. Nicotinic acid (niacin, vitamin PP, vitamin B3) is widely used in medicine as drug which has a vasodilating effect, prevents the accumulation of cholesterol and normalizes the heart function. Isonicotinic (4-pyridinecarboxylic) acid is used for the production of valuable anti-tuberculosis drugs, antidepressants, etc. However, nicotinic and isonicotinic acids have various side effects: skin hyperemia, pruritus, formation of stomach peptic ulcers, liver dysfunction and hyperglycemia. To reduce the severity of side effects, their slightly soluble salts, esters or amides are obtained. The synthesis of nicotinic and isonicotinic acid esters with vanillin benzaldehydes, cholesterol, 8-hydroxyquinoline, quinine and (4,5-dichloroisothiazol-3-yl)methanol is described. Esters were obtained by acylation of hydroxybenzaldehydes and alcohols with nicotinic and isonicotinic acid hydrochlorides in the presence of triethylamine in anhydrous methylene chloride. The IR- UV- and NMR spectra of the compounds obtained are presented.