Water-proton relaxivities of DNA oligomers carrying TEMPO radicals.
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.
Sato
Yuichiro
Y
Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582 Japan.
Hayashi
Hiroyuki
H
Okazaki
Manami
M
Aso
Mariko
M
Karasawa
Satoru
S
Ueki
Shoji
S
Suemune
Hiroshi
H
Koga
Noboru
N
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*
D003497:Cyclic N-Oxides; D009838:Oligodeoxyribonucleotides; D011522:Protons; D013113:Spin Labels; D014867:Water; C003959:TEMPO