title: Photoreaction of 5-methoxypsoralen with thymidine. Isolation and characterization of a pyrone-side monoadduct involving the pyrimidine methyl group.
abstract: The UVA-mediated photoreaction of 5-methoxypsoralen (5-MOP) with thymidine has been investigated in the dry state. Under these conditions, the main products are 5-MOP pyrone-side monoadducts to thymidine. We report the isolation and characterization of an unusual 5-MOP-thymidine photoproduct. The assignment of the photoadduct was achieved on the basis of extensive spectroscopic measurements (UV, mass spectrometry (MS), 1H and 13C nuclear magnetic resonance (NMR), nuclear Overhauser effect (NOE) experiments). The formation of the photoadduct, which is rationalized in terms of a radical mechanism, appears to involve, in a covalent bond, the C-4 pyrone moiety of 5-MOP and the methyl group of thymidine.
authors.affiliation: CEA/Département de Recherche Fondamentale sur la Matière Condensée, SESAM/LAN, Grenoble, France.
authors.forename: C
authors.initials: C
authors.lastname: Anselmino
authors.forename: J
authors.initials: J
authors.lastname: Cadet
mesh_terms: D000078223:5-Methoxypsoralen; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D008730:Methoxsalen / Q000031:analogs & derivatives* / Q000737:chemistry / Q000528:radiation effects; D015394:Molecular Structure; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet; D013936:Thymidine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: C093099:5-methoxypsoralen-thymidine adduct; D000078223:5-Methoxypsoralen; D008730:Methoxsalen; D013936:Thymidine