title: Acid-base properties and DNA-binding of water soluble N-confused porphyrins with cationic side-arms.
abstract: Water soluble N-confused porphyrins, 5,10,15,20-tetrakis(alpha-pyridinio-p-tolyl)-2-aza-21-carbaporphyrin (pPyNCP) and its N-methyl derivative, 2-N-methyl-5,10,15,20-tetrakis(alpha-pyridinio-p-tolyl)-2-aza-21-carbaporphyrin (NMe-pPyNCP), have been synthesized by introducing cationic side-arms at the meso-positions of N-confused porphyrin. Their acid-base properties (pK(1-4)) and DNA-binding ability in aqueous solutions were elucidated in comparison with the corresponding porphyrin derivative. Photophysical behaviors of pPyNCP were largely influenced by buffer compositions and DNA structures, whereas NMe-pPyNCP is considerably robust against these factors. In addition, significant enhancement of the fluorescence was observed with NMe-pPyNCP by the addition of DNA. The unique properties of pPyNCP and NMe-pPyNCP stem from the confused pyrrole rings in the macrocycle.
authors.affiliation: Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan.
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Ikawa
authors.forename: Shoji
authors.initials: S
authors.lastname: Moriyama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Harada
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Furuta
mesh_terms: D004247:DNA / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry*; D012995:Solubility; D014867:Water / Q000737:chemistry*
chemical_list: D004277:DNA, Single-Stranded; D011166:Porphyrins; D014867:Water; D004247:DNA; D009584:Nitrogen