title: The relationship between the chemical structures of dihydropyrazine derivatives and DNA strand-breakage activity.
abstract: Dihydropyrazine, a compound derived from sugars, possesses DNA strand-breakage activity. The relationship between the activity as assayed using pBR 322 ccc-DNA and the chemical structures of derivatives of dihydropyrazine (DHPs) has been investigated. The addition of Cu(2+) enhanced the activity remarkably. The introduction of a methyl or phenyl group onto the DHP ring or a cyclohexyl group fused onto the DHP ring also increased the activity. These properties indicated that the activity was due to the facility of electron release from the DHP ring, followed by radical generation. The determination of ionization potential and electrostatic potential values, and bond dissociation energy via semi-empirical MO calculations suggested strongly that the activity is induced by a DHP ring structure that contains a configuration suitable for hyperconjugation.
authors.affiliation: Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto, Japan. tadayama@ph.sojo-u.ac.jp
authors.forename: Tadatoshi
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Ito
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Kashige
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Nakahara
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Harano
mesh_terms: D004247:DNA / Q000737:chemistry*; D004249:DNA Damage; D004578:Electron Spin Resonance Spectroscopy; D011719:Pyrazines / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D011719:Pyrazines; D004247:DNA