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|Section2= |Section3= |Section7= |Section9= }} Coumarin (; ''2H''-chromen-2-one) is a fragrant organic chemical compound in the benzopyrone chemical class, which is a colorless crystalline substance in its standard state. It is a natural substance found in many plants. The name comes from a French term for the tonka bean, ''coumarou'', one of the sources from which coumarin was first isolated as a natural product in 1820. It has a sweet odor, readily recognised as the scent of new-mown hay, and has been used in perfumes since 1882. Sweet woodruff, sweet grass and sweet-clover in particular are named for their sweet (i.e., pleasant) smell, which in turn is due to their high coumarin content. When it occurs in high concentrations in forage plants, coumarin is a somewhat bitter-tasting appetite suppressant, and is presumed to be produced by plants as a defense chemical to discourage predation. Coumarin is used in certain perfumes and fabric conditioners. Coumarin has been used as an aroma enhancer in pipe tobaccos and certain alcoholic drinks, although in general it is banned as a flavorant food additive, due to concerns regarding its hepatotoxicity in animal models. Coumarin was first synthesized in 1868. It is used in the pharmaceutical industry as a precursor reagent in the synthesis of a number of synthetic anticoagulant pharmaceuticals similar to dicoumarol, the notable ones being warfarin (brand name Coumadin) and some even more potent rodenticides that work by the same anticoagulant mechanism. So-called "coumarins" (modified coumarins) are a type of vitamin K antagonists. Pharmaceutical (modified) coumarins were all developed from the study of sweet clover disease; see warfarin for this history. However, unmodified coumarin itself, as it occurs in plants, has no effect on the vitamin K coagulation system, or on the action of warfarin-type drugs. Coumarin has clinical medical value by itself, as an edema modifier. Coumarin and other benzopyrones, such as 5,6-benzopyrone, 1,2-benzopyrone, diosmin, and others, are known to stimulate macrophages to degrade extracellular albumin, allowing faster resorption of edematous fluids.〔Casley-Smith, J. R., et al. (1993). (Treatment of lymphedema of the arms and legs with 5,6-benzo-(alpha)-pyrone. ) ''NEJM'' 329(16) 1158–63.〕〔(Review of benzypyrone drugs and edema. ) Lymphoedema.org〕 Other biological activities that may lead to other medical uses have been suggested, with varying degrees of evidence. Coumarin is also used as a gain medium in some dye lasers,〔Schäfer, F. P. (Ed.). ''Dye Lasers'', 3rd Ed. Berlin, Springer-Verlag. 1990.〕〔Duarte, F. J. and L. W. Hillman (Eds.). ''Dye Laser Principles''. New York, Academic. 1990.〕〔Duarte, F. J. ''Tunable Laser Optics''. New York, Elsevier-Academic. 2003. Appendix of Laser Dyes.〕 and as a sensitizer in older photovoltaic technologies.〔U.S. Pat. No. 4175982 to Loutfy et al., issued Nov 27 1978 to Xerox Corp.〕 == History == The word "Tonka" for tonka beans is taken from the Galibi (Carib) tongue spoken by natives of French Guiana (one source for the plant); it also appears in Tupi, another language of the same region, as the name of the tree. The old genus name, ''Coumarouna'', was formed from another Tupi name for tree, kumarú. The French word for Tonka bean, ''coumarou,'' is from this name. Coumarin, named for ''coumarou'' was first isolated from Tonka beans and sweet clover in 1820 by A. Vogel of Munich, who initially mistook it for benzoic acid.〔See: *Vogel, A. (1820). Darstellung von Benzoesäure aus der Tonka-Bohne und aus den Meliloten - oder Steinklee - Blumen (Preparation of benzoic acid from tonka beans and from the flowers of melilot or sweet clover). ''Annalen der Physik'' 64(2) 161-66. *Vogel, A. (1820). De l'existence de l'acide bezoïque dans la feve de tonka et dans les fleurs de mélilot (On the existence of benzoic acid in the tonka bean and in the flowers of melilot). ''Journal de Pharmacie'' 6 305-09. (pages 307-08 ).〕 Also in 1820, Nicholas Jean Baptiste Gaston Guibourt (1790-1867) of France independently isolated coumarin, but he realized that it was not benzoic acid.〔Guibourt, N. J. B. G. ''Histoire Abrégée des Droques Simples'' (''Abridged History of Simple Drugs''). Volume 2. Paris, L. Colas. 1820. (pages 160-161 ).〕 In a subsequent essay he presented to the pharmacy section of l'Académie royale de Médecine, Guibourt named the new substance "coumarine".〔See: * ''Journal de Chimie Médicale, de Pharmacie et de Toxicologie'', 1 : (303 ) (1825): "… plus récemment, dans un essai de nomenclature chimique, lu à la section of Pharmacie de l'Académie royale de Médecine, il l'a désignée sous le nom de ''coumarine'', tiré du nom du végétal ''coumarouna odorata'' …" (… more recently, in an essay on chemical nomenclature, (was ) read to the pharmacy section of the Royal Academy of Medicine, he () designated it by the name "coumarine", derived from the name of the vegetable ''Coumarouna odorata'' …). * Guibourt, N. J. B. G. ''Histoire Naturelle des Drogues Simples'', ... , 6th ed. Paris, J. B. Baillière et fils. 1869. (bottom of page 377 ): "… la matière cristalline de la fève tonka (matière que j'ai nommée ''coumarine'') …" (… the crystaline matter of the tonka bean (matter that I named ''coumarine'' …).〕 In 1835, the French pharmacist A. Guillemette proved that Vogel and Guibourt had isolated the same substance.〔Guillemette, A. (1835) (Recherches sur la matière cristalline du mélilot ) (Research into the crystalline material of melilot). ''Journal de Pharmacie'' 21 172-78.〕 Coumarin was first synthesized in 1868 by the English chemist William Henry Perkin.〔Perkin, W. H. (1868). (On the artificial production of coumarin and formation of its homologues. ) ''Journal of the Chemical Society'' 21 53-63.〕 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「Coumarin」の詳細全文を読む スポンサード リンク
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