Coumarins are widely distributed polyphenolic compounds in the plant world . Isolated over 1000 different structures of coumarin. Like most of the compounds and coumarins fenilpropanskih arise from phenylalanine via cimetne and p-coumarinacid. Known as: simple coumarins, eskuletin, scopoletin, umbeliferon, dikumarini et al.
The plant tissue may be present:
- heterozidi o-hydroxy-Z (E)-cimetne acid;
- heterozidi coumarin;
- free coumarins.
From heterozida hydroxy acids cimetnihcoumarins occur and spontaneous hydrolysis heterozida laktonizacijom during the drying process (the process is accompanied by the formation of specific smell mown hay).
Simple coumarins differ in substituents, most often hydroxyl and methoxy groups, thus they are called hydroxy or metoksikumarini. Coumarins are the most widespread and umbeliferon herniarin.
Like most of the compounds and coumarins fenilpropanskih arise from phenylalanine via cimetne and p-coumarin acid. Important steps:
- introduction of hydroxyl groups in ortho position;
- isomerization process of the double bond is fotokatalizovan;
- laktonizacije spontaneous creation and structure of coumarin;
- further prenilovanje;
- subsequent cyclization and formation of furan-and pyrano coumarin.
Formed by hydrolysis Aesculin eskuletin (6,7-dihydroxycoumarin) and coumarin glukoza.Izvor this bark is chestnut.
Coumarins suberosin, ksantiletin, ksantoksiletin isolated from Citrus grandis L. aurapten from Severinia huxifolia L. and Poncirus trifoliate poncitrin from L. (Teng et al., 1992). From Citrus sinensisL. isolated five coumarin (Bayet et al., 2007).
Dikumarini caused by the two coumarin molecules bonded with methylene bridge. Until such a connection occurs during the fermentation process, but only under specific conditions: in the presence of microorganisms and plant weight when wet. The best known compound of this structure and the dikumarin plesnjivog isolated from hay, which contained a lot kokoca (Melilotus officinalis).
1. Teng CM, Huey-Lin Li, Tian-Shung Wu, Shiow-Chyna Huang and Tur-Fu Huang, Antiplatelet actions of some coumarin compounds isolated from plant sources, Thrombosis Research Volume 66, Issue 5, 1 June 1992, Pages 549-557
2. Bayet C., C. Fazio, N. Darbour1, O. Berger, I. Raad, A. Chaboud, C. Dumontet and D. Guilet, Modulation of P-glycoprotein Activity by Acridones and Coumarins from Citrus sinensis, Phytotherapy RESEARCH Phytother. Res. 21, 386-390 (2007)