title: Spin-trapping of the p-benzyne intermediates from ten-membered enediyne calicheamicin gamma1I.
abstract: In the presence of thiols, the ten-membered-ring enediyne calicheamicin gamma1I generates a p-benzyne biradical that initiates oxidative cleavage of double-stranded DNA. Application of spin-trapping has successfully provided ESR and mass spectroscopic evidence for the formation of the monoadducts with phenyl tert-butyl nitrone (PBN). [reaction: see text].
authors.affiliation: Department of Chemistry, Columbia University, New York, New York 10027, USA. tu2110@columbia.edu
authors.forename: Toyonobu
authors.initials: T
authors.lastname: Usuki
authors.forename: Koji
authors.initials: K
authors.lastname: Nakanishi
authors.forename: George A
authors.initials: GA
authors.lastname: Ellestad
mesh_terms: D000617:Aminoglycosides / Q000737:chemistry*; D003497:Cyclic N-Oxides / Q000737:chemistry; D003500:Cyclization; D004247:DNA / Q000187:drug effects; D004249:DNA Damage; D003903:Deuterium; D004578:Electron Spin Resonance Spectroscopy; D053281:Enediynes / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D013058:Mass Spectrometry; D008847:Micromonospora / Q000737:chemistry; D010084:Oxidation-Reduction; D019097:Spin Trapping
chemical_list: D000617:Aminoglycosides; D003497:Cyclic N-Oxides; D053281:Enediynes; C055955:calicheamicin gamma(1)I; C029217:phenyl-N-tert-butylnitrone; D000431:Ethanol; D004247:DNA; D003903:Deuterium