6-Hydroxynicotinic acid, also known as 6-hydroxy-3-pyridinecarboxylic acid, is an organic compound with the chemical formula C6H5NO3. It is a derivative of nicotinic acid (vitamin B3), featuring a hydroxyl group attached to the 6th carbon position of the pyridine ring. 6-HydroxynicotinicAcid is a white crystalline solid that is soluble in water and has various applications in the pharmaceutical and chemical industries. It is used as an intermediate in the synthesis of various drugs, agrochemicals, and other精细化工 products. Due to its potential applications and properties, 6-hydroxynicotinic acid has been a subject of interest for researchers in the field of organic chemistry.