title: A novel series of DNA triple helix-binding ligands.
abstract: We have examined the effect of a series of substituted imidazothioxanthones on the stability of an intermolecular DNA triple helix by DNase I footprinting. We find that several of these compounds promote the formation of a complex between T5C5 and the target site A6G6.C6T6, suggesting that they bind specifically to triplex DNA. The only inactive derivative lacked a protonatable function in the side chain, suggesting that this is an essential feature for triplex stabilization. These compounds, which are amongst the first triplex-binding ligands which possess an uncharged chromophore, are selective for the T.AT rather than the C+.GC triplet.
authors.affiliation: Department of Physiology & Pharmacology, University of Southampton, Bassett Crescent East, United Kingdom.
authors.forename: K R
authors.initials: KR
authors.lastname: Fox
authors.forename: D E
authors.initials: DE
authors.lastname: Thurston
authors.forename: T C
authors.initials: TC
authors.lastname: Jenkins
authors.forename: A
authors.initials: A
authors.lastname: Varvaresou
authors.forename: A
authors.initials: A
authors.lastname: Tsotinis
authors.forename: T
authors.initials: T
authors.lastname: Siatra-Papastaikoudi
mesh_terms: D004247:DNA / Q000737:chemistry / Q000187:drug effects*; D018983:DNA Footprinting; D003850:Deoxyribonuclease I / Q000378:metabolism; D014966:Xanthenes / Q000737:chemistry / Q000494:pharmacology*; D044004:Xanthones
chemical_list: D014966:Xanthenes; D044004:Xanthones; C051802:triplex DNA; D004247:DNA; C009689:xanthone; D003850:Deoxyribonuclease I