Carbon and Proton Nuclear Magnetic-relaxation Study of Thymidine Thymidine Interaction In Solution

The nucleoside thymidine has been used as a model system to study the effects of the presence of intra- and intermolecular interactions on both carbon spin-lattice relaxation rates R1 and selective {Ha}C nuclear Overhauser effects (NOEs). The carbon R1 analysis permits the determination of the correlation times of each moiety of thymidine. These findings, and a careful analysis of the selective {Ha}C NOEs, point out the presence of a dimeric complex in solution in which stacking and hydrogen-bond interactions play an important role in the stabilization of this structure. Moreover, the effect induced on selective {Ha}C NOEs by the presaturation of exchangeable protons has been considered and a method to resolve this problem proposed. © 1987 American Chemical Society.