Furano-coumarins

In summary, studies with single compounds demonstrate that furano-coumarins and their dimers are primarily responsible for the interactions of GFJ and drugs. 

The possibility of zonal sample dosage in equilibrium conditions (after the front of mobile-phase and continuous-chromatogram development, which is provided by a horizontal sandwich chamber) was utilized by Glowniak et al. [3] in preparative chromatography of simple coumarins and furano-coumarins found in Archangelica fruits, performed with a short-bed continuous development (SB-CD) technique. 

The latter possibility was employed by Wawrzynow-icz and Waksmundzka-Hajnos for micropreparative TLC isolation of furano-coumarins tom Archangelica, Pastinaca, and Heracleum fruits on silica gel, silanized gel, and florisil. 

Rutae herba can be characterized by its coumarins (e.g. rutamarin), the furano-coumarins (e.g. bergapten, psoralen) as well as the furanoquinoline alkaloids (e.g, kokusagine, Y-fagarine) and the flavonol glycoside rutin. 

Koenigs, L.L. and W.F. Trager (1998). Mechanism-based inactivation of P450 2A6 by furano-coumarins. Biochemistry 31, 10047-10061. 

Zobel, A.M., and S.A. Brown. 1990. Dermatitis-inducing furano-coumarins on leaf surfaces of eight species of mtaceous and umbelliferous plants. /. Chem. Ecol. 16(3) 693-700. 

UV spectroscopy has only little significance for the direct analysis of essential oils due to the inability to provide uniform information on individual oil components. However, for testing the presence of furano-coumarins in various citrus oils, which can cause photodermatosis when applied... 

Effects of UV irradiation in the presence of furano-coumarins have also been studied with proteins, especially enzymes, and it is now clear that photobinding effects are not confined to nucleic acids. Both linear and angular furanocoumarins bind covalently to proteins in reactions highly dependent on structure. Enzymes are significantly inactivated, as shown in Table 1. The linear isomers appear generally to be most inhibitory, but there is great variation with the structure of both the coumarin and the protein. 

Long-distance OPLC is a novel form of OPLC, in which chromatograms are developed over a long distance with optimal (empiric) mobile-phase flow. Used in combination with specialized equipment designs, it produces high performance (70,000 to 80,000 of theoretic plates) and excellent resolution. Botz et al. [6], who initiated long-distance OPLC, proved its efficiency in separation of eight furano-coumarin isomers and in isolation of furanocoumarin complex from Peucedanum palustre roots raw extract. 

This newer technique has been successfully applied to furano-coumarins from spring parsley 564). 

Furanocoumarins have been used in folk medicine for a long time. The Indian sacred book Atharva Veda describes the treatment of leukoderma (vitiligo) using a poultice from a plant now known as Psoralea corylifolia, and the ancient Egyptians used Ammi majus for the same disorder. The first furano-coumarin, 5-methoxypsoralen, was isolated in 1838 by Kalbrunner from bergamot oil. 

Furanocoumarins can photoreact with unsaturated fatty acids. For example, angelicin can form an adduct with linolenic acid. The unsaturated fatty acids may have important role in the phosphaddylinositol system, and furano-coumarin adducts may change the regulatoiy function of this system. Also, these adducts may inhibit phospholipase and thus prevent the activation of protein kinase C. The greatest extent of photobinding of xanthotoxin and 4,6,3 -trimethoxy was found in the lipid fraction followed by the protein and nucleic acid fractions [98]. 

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