title: 5-Methoxypsoralen photoadduct formation: conversion of monoadducts to crosslinks.
abstract: 5-Methoxypsoralen is often substituted for 8-methoxypsoralen in the photochemotherapy of psoriasis even though the nature of the resulting photadducts in cellular DNA has not been determined. A recent molecular mechanics study with a model oligonucleotide predicted that intercalated 5-methoxypsoralen molecules would tend to favor the preferential formation of 3,4-monoadducts. Such a result would be contrary to the photoadduct patterns observed with other psoralens. In this study we show that 5-methoxypsoralen photoadducts formation is, in fact, very similar to that for other psoralens, i.e., the primary photoadduct is the 4',5'-monoadduct which can be quantitatively converted to crosslink.
authors.affiliation: Department of Dermatology, Yale University Photobiology Laboratory, New Haven, CT 06510, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Amici
authors.forename: F P
authors.initials: FP
authors.lastname: Gasparro
mesh_terms: D000078223:5-Methoxypsoralen; D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D003432:Cross-Linking Reagents / Q000737:chemistry* / Q000528:radiation effects; D004247:DNA / Q000737:chemistry; D018736:DNA Adducts / Q000737:chemistry* / Q000528:radiation effects; D008730:Methoxsalen / Q000031:analogs & derivatives* / Q000737:chemistry / Q000528:radiation effects; D010777:Photochemistry; D010778:Photochemotherapy; D011067:Poly dA-dT / Q000737:chemistry; D011565:Psoriasis / Q000188:drug therapy; D014466:Ultraviolet Rays
chemical_list: D003432:Cross-Linking Reagents; D018736:DNA Adducts; D011067:Poly dA-dT; D000078223:5-Methoxypsoralen; D004247:DNA; D008730:Methoxsalen