title: 8-Azapsoralen derivatives: isolation and characterization of the furan-side cycloadducts with DNA.
abstract: The formation of C4-cycloadducts by photoreaction of eight methyl derivatives of 8-azapsoralen with DNA was studied. The main reaction involves the furan ring of the compounds and the 5,6 double bond of thymine giving cis-syn adducts, although a minor amount of a cycloadduct with cytosine was also isolated for 4,4'-dimethylazapsoralen. The role of the nitrogen atom appears to depend on the electronic effect, leading to a decrease in the reactivity of the pyrone ring. As with psoralens, the methyl groups increase both the lipophilicity and, with the exception of the 5,4',5'-trimethyl derivative, the photoreactivity. However, methyl groups do not appear to influence the chemistry of the photoaddition.
authors.affiliation: Department of Pharmaceutical Sciences, University of Padova, Padua, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Caffieri
authors.forename: D
authors.initials: D
authors.lastname: Vedaldi
authors.forename: A
authors.initials: A
authors.lastname: Chilin
authors.forename: A
authors.initials: A
authors.lastname: Pozzan
mesh_terms: D000818:Animals; D004247:DNA / Q000737:chemistry* / Q000302:isolation & purification; D011564:Furocoumarins / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D011838:Radiation-Sensitizing Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification; D012474:Salmon; D013329:Structure-Activity Relationship
chemical_list: D011564:Furocoumarins; D007202:Indicators and Reagents; D011838:Radiation-Sensitizing Agents; C087093:8-azapsoralen; D004247:DNA