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|Section2= |Section5= |Section6= |Section7= |Section8= }} Mandelic acid is an aromatic alpha hydroxy acid with the molecular formula C6H5CH(OH)CO2H. It is a white crystalline solid that is soluble in water and polar organic solvents. It is a useful precursor to various drugs. Since the molecule is chiral, it exists in either of two enantiomers as well as the racemic mixture, known as ''paramandelic acid''. ==Isolation, synthesis, occurrence== Mandelic acid was discovered while heating amygdalin, an extract of bitter almonds, with diluted hydrochloric acid. The name is derived from the German "Mandel" for "almond". Derivatives of mandelic acid are formed as a result of metabolism of adrenaline and noradrenaline by monoamine oxidase and catechol-O-methyl transferase. Mandelic acid is usually prepared by the acid-catalysed hydrolysis of mandelonitrile,〔Edwin Ritzer and Rudolf Sundermann "Hydroxycarboxylic Acids, Aromatic" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. 〕 which is the cyanohydrin of benzaldehyde. Mandelonitrile can also be prepared by reacting benzaldehyde with sodium bisulfite to give the corresponding adduct, forming mandelonitrile with sodium cyanide, which is hydrolyzed: : Alternatively, it can be prepared by base hydrolysis of phenylchloroacetic acid and dibromacetophenone. It also arises by heating phenylglyoxal with alkalis. It arises from the biodegradation of styrene, as detected in urine.〔Engström K, Härkönen H, Kalliokoski P, Rantanen J. "Urinary mandelic acid concentration after occupational exposure to styrene and its use as a biological exposure test" Scand. J. Work Environ. Health. 1976, volume 2, pp. 21-6.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「mandelic acid」の詳細全文を読む スポンサード リンク
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