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|Section2= |Section6= |Section7= }} Crystal violet or gentian violet (also known as methyl violet 10B or hexamethyl pararosaniline chloride) is a triarylmethane dye used as a histological stain and in Gram's method of classifying bacteria. Crystal violet has antibacterial, antifungal, and anthelmintic properties and was formerly important as a topical antiseptic. The medical use of the dye has been largely superseded by more modern drugs, although it is still listed by the World Health Organization. The name "gentian violet" was originally used for a mixture of methyl pararosaniline dyes (methyl violet), but is now often considered a synonym for crystal violet. The name refers to its colour, being like that of the petals of a gentian flower; it is not made from gentians or from violets. ==Production== A number of possible routes can be used to prepare crystal violet. The original procedure developed by the German chemists Kern and Caro involved the reaction of dimethylaniline with phosgene to give 4,4'-bis(dimethylamino)benzophenone (Michler's ketone) as an intermediate.〔 This was then reacted with additional dimethylaniline in the presence of phosphorus oxychloride and hydrochloric acid.〔 The dye can also be prepared by the condensation of formaldehyde and dimethylaniline to give a leuco dye:〔〔〔. Also available from (Scribd ).〕 :CH2O + 3 C6H5N(CH3)2 → CH(C6H4N(CH3)2)3 + H2O Second, this colourless compound is oxidized to the coloured cationic form: (A typical oxidizing agent is manganese dioxide). :CH(C6H4N(CH3)2)3 + HCl + 1/2 O2 → ()Cl + H2O 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「Crystal violet」の詳細全文を読む スポンサード リンク
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