Salicylic acid the OH group is "ortho" to the carboxyl group. It is also known as 2-hydroxybenzoic acid. It is poorly soluble in water (2 g/L at 20 °C). Aspirin (acetylsalicylic acid or ASA) can be prepared by the esterification of the phenolic hydroxyl group of salicylic acid with the acetyl group from acetic anhydride or acetyl chloride. Salicylic acid can also be prepared using the Kolbe-Schmitt reaction. Salicylic acid is used as a food preservative, a bactericidal and an antiseptic. Sodium salicylate is a useful phosphor in the vacuum ultraviolet spectral range, with nearly flat quantum efficiency for wavelengths between 10
Nonsteroidal anti-inflammatory drug inflammation and also used willow bark to mitigate them. On 25 April 1763, Edward Stone wrote to the Royal Society describing his observations on the use of willow bark-based medicines in febrile patients. The active ingredient of willow bark, a glycoside called salicin, was first isolated by Johann Andreas Buchner in 1827. By 1829, French chemist Henri Leroux had improved the extraction process to obtain about 30g of purified salicin from 1.5 kg of bark. By hydrolysis, salicin releases glucose and salicylic alcohol which can be converted into salicylic acid, both in vivo and through chemical methods. The acid is