title: Water-proton relaxivities of DNA oligomers carrying TEMPO radicals.
abstract: 5-Uridine derivative carrying a TEMPO radical (UST) was prepared and its single strand (ssUST) and a double strand (dsUST) with its complementary strand were obtained. Similarly, single strands carrying two and five radicals (ssUST2 and ssUST5, respectively) and the corresponding double strands (dsUST2 and dsUST5) were prepared. Their electron paramagnetic resonance (EPR) spectra showed typical anisotropic broadening in the high field line. The rotational correlation times, tau(R), estimated by analyzing the EPR spectra are 1.1 x 10(-10), 5.9 x 10(-10), and 14 x 10(-10) s for UST, ssUSTm, and dsUSTm, respectively. The water-proton relaxivities, r(1) and r(2), at 25 MHz, 0.59 T, and 25 degrees C, also increased in the same order and the r(1) values were 0.26, 0.41, and 0.56 mM(-1) s(-1) for UST, ssUSTm, and dsUSTm, respectively. The r(1) values of 1.00 and 2.06 mM(-1) s(-1) for dsUST2 and dsUST5, respectively, were obtained.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582 Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Sato
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hayashi
authors.forename: Manami
authors.initials: M
authors.lastname: Okazaki
authors.forename: Mariko
authors.initials: M
authors.lastname: Aso
authors.forename: Satoru
authors.initials: S
authors.lastname: Karasawa
authors.forename: Shoji
authors.initials: S
authors.lastname: Ueki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suemune
authors.forename: Noboru
authors.initials: N
authors.lastname: Koga
mesh_terms: D003497:Cyclic N-Oxides; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D009838:Oligodeoxyribonucleotides / Q000737:chemistry*; D011522:Protons; D012399:Rotation; D013113:Spin Labels; D014867:Water / Q000737:chemistry*
chemical_list: D003497:Cyclic N-Oxides; D009838:Oligodeoxyribonucleotides; D011522:Protons; D013113:Spin Labels; D014867:Water; C003959:TEMPO