Using 2H Labelling to Improve the NMR Detectability of Pyridine and its Derivatives by SABRE

By introducing a range of 2 H labels into pyridine and the para-substituted agents methyl isonicotinate and isonicotinamide we significantly improve their NMR detectability in conjunction with the Signal Amplification by Reversible Exchange (SABRE) process. We describe how the rates of T1 relaxation for the remaining 1 H nuclei are increased and show how this leads to a concomitant increase in the level of 1 H and 13 C hyperpolarization that can ultimately be detected