White, crystalline solid organic compound used chiefly to make aspirin and other pharmaceutical products, including methyl salicylate (oil of wintergreen , for medicines and flavourings), phenyl salicylate (for sunburn creams and pill coatings), and salicylanilide (a cutaneous fungicide ).
Its molecular structure, with the formula C 6 H 4 (OH)COOH, consists of a six-membered aromatic ring (see aromatic compound ) having a hydroxyl group (―OH) and a carboxyl group (―COOH) bonded to adjacent carbon atoms; as such, it is both a phenol and a carboxylic acid . It and certain derivatives occur naturally in some plants, particularly species of Spiraea and Salix ( willow ). Large amounts are used in producing certain dyes.