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Coumarin dyes are extensively used as gain media in blue-green tunable organic dye lasers. [14] [15] [16] Among the various coumarin laser dyes are coumarins 480, 490, 504, 521, 504T, and 521T. [16] Coumarin tetramethyl laser dyes offer wide tunability and high laser gain, [17] [18] and they are also used as active medium in coherent OLED emitters.
Coumarin (/ ˈ k uː m ər ɪ n /) or 2H-chromen-2-one is an aromatic organic chemical compound with formula C 9 H 6 O 2.Its molecule can be described as a benzene molecule with two adjacent hydrogen atoms replaced by an unsaturated lactone ring −(CH)=(CH)−(C=O)−O−, forming a second six-membered heterocycle that shares two carbons with the benzene ring.
Coumarin This molecule does not affect coagulation: 4-Hydroxycoumarin This molecule does not affect coagulation, but is a known carcinogen in diesel fumes and tobacco smoke; in the latter, it probably derives from combustion of the tobacco additive coumarin. Dicumarol This molecule was the first discovered 4-hydroxycoumarin anticoagulant.
4-Hydroxycoumarin is a coumarin derivative with a hydroxy group at the 4 ... 4-Hydroxycoumarin is an important fungal metabolite from the precursor coumarin, ...
Aesculetin (also known as esculetin, 6,7-dihydroxycoumarin and cichorigenin) is a derivative of coumarin. It is a natural lactone that derives from the intramolecular cyclization of a cinnamic acid derivative. It is present in chicory and in many toxic and medicinal plants, in form of glycosides and caffeic acid conjugates. [2]
Hydroxylation of cinnamic acid in the 4-position by trans-cinnamate 4-monooxygenase leads to p-coumaric acid, which can be further modified into hydroxylated derivatives such as umbelliferone. Another use of p -coumaric acid via its thioester with coenzyme A , i.e. 4-coumaroyl-CoA , is the production of chalcones .
Umbelliferone, also known as 7-hydroxycoumarin, hydrangine, skimmetine, and beta-umbelliferone, is a natural product of the coumarin family. It absorbs ultraviolet light strongly at several wavelengths. There are some indications that this chemical is antimutagenic, [1] it is used in sunscreens. [2]
It is a derivative of coumarin, a bitter-tasting but sweet-smelling substance made by plants that does not itself affect coagulation, but which is (classically) transformed in mouldy feeds or silages by a number of species of fungi, into active dicoumarol.