title: Psoralenamines. 3. Synthesis, pharmacological behavior, and DNA binding of 5-(aminomethyl)-8-methoxy-, 5-[[(3-aminopropyl)oxy]methyl]-, and 8-[(3-aminopropyl)oxy]psoralen derivatives.
abstract: A series of derivatives of 5-(aminomethyl)-8-methoxypsoralens, 8-[(3-aminopropyl)oxy]psoralens, and 5-[[[3-(tri-methylammonio)propyl]methyl]-8-methoxypsoralen has been synthesized and their potential as PUVA reagents examined. While the DNA association constants of selected psoralens were found to be 10(5)-10(6)L mol-1, corresponding to efficient binding, flow linear dichroism studies indicated that only the 8-substituted psoralens bind to DNA by intercalation. Furthermore, the ability to photoinduce interstrand cross-links in calf thymus DNA, in vitro, was as efficient as that of 8-methoxypsoralen for the 8-substituted psoralens, which were up to 25 times as efficient as the 5-substituted psoralens. Four of the psoralens studied were radiolabeled and used to study photobinding to DNA. Analogously to the cross-binding results, the 8-substituted psoralens were more efficiently photobound than the 5-substituted, while only slight differences were found in the photobinding-cross-linking ratio. The photoreactivity of the aminopsoralens toward cyclohexene and 2'-deoxythymidine was enhanced compared to that of 8-methoxypsoralen, the effect being most pronounced when the amino group is close to the furocoumarin ring system. Most of the new compounds were less photocytotoxic than 8-methoxypsoralen to NHIK 3025 cells, in vitro, and they caused less light-induced DNA interstrand cross-linking, in situ, in these cells. A clear correlation between the photocytotoxicity and the DNA cross-linking ability of the psoralens was observed. Several of the derivatives showed more pronounced effects in the light-dependent skin thickening (inflammatory) test on mice than 8-methoxypsoralen. No correlation between DNA cross-linking capacity, in vitro, and skin phototoxicity was found for this series of psoralens.
mesh_terms: D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D003432:Cross-Linking Reagents; D004247:DNA / Q000378:metabolism*; D005260:Female; D011564:Furocoumarins / Q000138:chemical synthesis / Q000494:pharmacology*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D051379:Mice; D011701:PUVA Therapy; D010777:Photochemistry; D010778:Photochemotherapy; D011565:Psoriasis / Q000188:drug therapy; D012867:Skin / Q000187:drug effects; D013329:Structure-Activity Relationship
chemical_list: D003432:Cross-Linking Reagents; D011564:Furocoumarins; D004247:DNA