Methoxsalen

The alkaloid reserpiae [50-55-5] which is isolated from the roots of Kauwoljia serpentina T., contains a gaUate trimethyl ether moiety. Reserpiae is used as an antihypertensive and a tranquilizer. A vinylogue of reserpiae, rescinnamine [24815-24-5] is also an antihypersensitive (75). Methoxsalen [298-81-7] (8-methoxypsoralen 7JT-9-methoxy-furo [3,2- ] [l]benzopyran-7-one) (21), a furocoumatia that occurs ia plants, eg, l eguminosae and Umbelliferae is used ia the treatment of vitiligo, as a suntanning promoter, and as a sunburn protectant. It is also available by synthesis (76). 

Methoxypsoralen (Methoxsalen) [298-81-7] plus ultraviolet A radiation (Vol. 24, Suppl. 7 1987)... 

There is also a wholly synthetic route to Methoxsalen as outlined by Kleeman 8i Engel. 

Metrizoic acid Diazomethane Diazepam Epirizole Methoxsalen Pyrimethamine Dibenzo[a,el cycloheptadiene Butriptyline... 

C2H3CIO2 79-11-8) see Acediasulfone Acefylline Adrafinil Adrenalone Carbocisteine Diodone Mefexamide Methoxsalen Modafinil Nitrofurantoin Pifoxime Praziquantel Propyliodone... 

There is a bath PUVA and an oral PUVA. Bath PUVA therapies involve soaking in a bath of psoralens liquid for 15 minutes prior to UVA treatment. Oral PUVA involves taking an oral psoralens capsule the day prior to a UVA treatment. Oral psoralens such as methoxsalen cause nausea in many patients. Other adverse effects of PUVA include photosensitivity, which necessitates the use of eye protection and UVA-blocking sunscreen for 24 hours after a PUVA treatment macular melanosis at exposed sites (PUVA lentigines) and increased risk of skin cancers, especially squamous cell carcinoma.21... 

Another method that may have less carcinogenic potential is to topically deliver the photosensitizer (methoxsalen) to the skin by adding it to bath water (bath PUVA) or as a topical cream (PUVA cream) instead of through systemic administration. Advantages of this approach include minimal risk of systemic effects, overall reduction of PUVA dose to one-... 

The ancient Egyptians used the plantAmmi majus, which contains methoxsalen (sometimes called 8-methoxypsoralen, based on a now obsolete method of naming fused heterocycles indexed in Chemical Abstracts under furo[3,2-g][l]benzopyran-7-one, 9-methoxy-, 249), in combination with sunbathing to... 

This work finally resulted in a new protocol for treating psoriasis, a chronic skin disease that can be seriously debilitating. The patient receives successive oral doses of methoxsalen followed by ultraviolet irradiation of the affected areas of skin. The procedure effectively controls psoriasis, and with improvements incorporated over the past twenty years it has become a standard therapy. Related procedures bring relief from several other skin diseases. In addition, the combination of psoralens and light has a key role in a promising treatment now under development for a white blood cell cancer. 

Letteron P, Degott C, Labbe G, et al. 1987. Methoxsalen decreases the metabolic activation and prevents the hepatotoxicity and nephrotoxicity of chloroform in mice. Toxicol Appl Pharmacol 91 266-273. 

Several compounds are inhibitors of CYP2A6-mediated nicotme metabolism m vitro, mcludmg methoxsalen (8-methoxypsoralen), tranylcypromine, tryptamine and coumarin (Le Gal et al. 2003 MacDougall et al. 2003 Nakajima et al. 1996 Zhang et al. 2001). Raloxifene is a potent inhibitor of aldehyde oxidase and it has been shown to inhibit the formation of cotinine from nicotme-A -iminium ion in human liver cytosol (Obach 2004). 

Zhang W, Kilicarslan T, Tyndale RF, Sellers EM (2001) Evaluation of methoxsalen, tranylcypromine, and tryptamine as specific and selective CYP2A6 inhibitors in vitro. Drug Metab Dispos 29(6) 897-902... 

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