Isonicotinamide

Isonicotinamide, also known as 4-pyridinecarboxamide or isonicotinamide, is an organic compound that represents the amide derivative of isonicotinic acid. It is an isomer of nicotinamide, which is the 3-pyridinecarboxamide. The molecule consists of a pyridine ring bearing a carboxamide substituent at the 4-position.

Preparation and properties: Isonicotinamide is typically prepared by amidation of isonicotinic acid or its derivatives. It is a stable crystalline solid and is soluble in some polar solvents, with solubility depending on the solvent and conditions. As an amide of a pyridine carboxylic acid, it exhibits the characteristic stability of amide functionalities and the basicity associated with the pyridine ring, though the ring nitrogen is modulated by the adjacent carboxamide group.

Applications: It is mainly used as a chemical building block in organic synthesis and medicinal chemistry. It serves as a precursor or intermediate in the preparation of heterocyclic compounds and, in some cases, as a ligand in metal coordination chemistry. Isonicotinamide has also appeared in crystallography and crystal engineering studies as a potential co-crystal former with other pyridine-containing substrates.

Safety: Isonicotinamide should be handled with standard laboratory precautions for amide-containing compounds. There is limited toxicity data in general references, and it is not known as a marketed pharmaceutical agent. Standard PPE and good laboratory practices are advised when handling this compound.