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 doubles trands (dsUST2 and dsUST5) were prepared. Their electron paramagnetic resonance (EPR) spectra showed typical anisotropic broadening in the high field line. The rotational correlation times, τR, estimated by analyzing the EPR spectra are 1.1 × 10-10, 5.9 × 10-10, and 14 × 10-10 s for UST, ssUSTm, and dsUSTm, respectively. The water-proton relaxivities, r1 and r2, at 25 MHz, 0.59 T, and 25°C, also increased in the same order and the r1 values were 0.26, 0.41, and 0.56 mM-1 s-1 for UST, ssUSTm, and dsUSTm, respectively. The r1 values of 1.00 and 2.06 mM-1 s -1 for dsUST2 and dsUST5, respectively, were obtained.
All Science Journal Classification (ASJC) codes
- Materials Science(all)