55-22-1

white to light yellow crystal powder

Isonicotinic acid is a metabolite of isoniazid. It is an isomer of nicotinic acid. The chronic toxicity of isonicotinic acid is slightly higher than that of isonicotinic acid hydrazide ( INH ) .
Isonicotinic acid is a moderately basic compound (based on its pKa). Isonicotinic acid is an organic compound with a carboxyl group on a pyridine ring. The carboxyl group for isonicotinic acid is on the 4-position instead of the 3-position for nicotinic acid. It is an isomer of nicotinic acid. Isonicotinic acid is a metabolite of isoniazid.
Isonicotinic acid considered to be inactive isomer of nicotinic acid. Isonicotinic acid is a metabolite of pyridine-4-carboxy hydrazide (isonicotinyl hydrazide; isoniazid) a front-line weapon in the battle against tuberculosis. Isonicotinic acid and its derivatives are used in manufacturing pharmaceuticals and agrochemicals.
Used in the biological study of differentiation induced by nicotinic acid, nicotinamide and isonicotinic acid in human leukemia cell lines

Isonicotinic acid (IN) can be used as:
An organocatalyst in the one pot four component condensation reaction, to synthesize pyranopyrazoles based heterocyclic compounds.
An organic ligand for the preparation of copper(I) halide coordination polymer [CuBr(IN)]n, by hydrothermal method.
As a starting material for the synthesis of cation-dimers with potent antimalarial activity.

ChEBI: A pyridinemonocarboxylic acid in which the carboxy group is at position 4 of the pyridine ring.

Isonicotinic acid is synthesized by continuous oxidation with 4-methylpyridine as raw material and vanadium pentoxide as catalyst. The purity of the industrial product isonicotinic acid is more than 95%, and the yield of the above method is 70-75%. The consumption of 4-methylpyridine per ton of product is 1070kg.

Store at -20°C

Crystallise the acid repeatedly from water and dry it under vacuum at 110o or sublime it at 260o/15mm (m 319o). [Beilstein 22 III/IV 518, 22/2 V 188.]