Copper aspirinate Copper aspirinate Copper(II) aspirinate is an aspirin chelate of copper(II) cations (Cu). It is used to treat rheumatoid arthritis. Copper aspirinate can be prepared by several methods. In one route of preparation, an excess of acetylsalicylic acid is dissolved in aqueous sodium carbonate. Sodium hydroxide is not suitable for this purpose, because it will hydrolyse acetylsalicylic acid ("ASA") into salicylic acid and sodium acetate. The resulting solution is then filtered to remove any undissolved acetylsalicylic acid and is mixed with a solution containing Cu cations (copper(II) sulfate is suitable), precipitating bright blue crystals of copper aspirinate immediately. The crystals can
3-Methylbutanoic acid dioxide and sometimes sorbic acid, by mixing in alcoholic spirit to give a fortified wine of sufficient strength to kill all yeast and bacteria, or by pasteurization. Isovaleric acid can also be found in beer, and, excepting some English–style ales, is usually considered a flaw. It can be produced by the oxidation of hop resins, or by "Brettanomyces" yeasts present. Isovaleric acid has been used to synthesize β-hydroxyisovaleric acid – otherwise known as β-hydroxy β-methylbutyric acid – via microbial oxidation by the fungus "Galactomyces reessii". 3-Methylbutanoic acid 3-Methylbutanoic acid, also known as β-methylbutyric acid or more commonly isovaleric acid, is