allows, for example, to utilize them for altering the activity of proteins, controlling mitosis with single-cell spatial precision, studying the biological role of specific receptors, and to store solar energy. Of great interest for advanced magnetic resonance applications is the ability of cis-ABZ to possess strong nonequilibrium polarization (called hyperpolarization) of N nuclear spins through interaction with para-hydrogen molecules (i.e. a dihydrogen isomer with protons having zero total spin) in reversible exchange with Ir-complex (signal amplification by reversible exchange, SABRE), which drastically enhances the inherently low sensitivity of N NMR. In addition, the trans-ABZ isomer with two N nuclear isotopes has a long-lived spin state (LLS) with a lifetime of about 18 minutes, which exceeds the N magnetization relaxation time at room temperature by two orders of magnitude. Long lived spin states gain a particular interest in magnetic resonance, due to their higher sensitivity in studies of slow dynamical process, improved contrast for ligand-protein screening by NMR, and ability to store hyperpolarization for minutes, which is crucial for most practical applications. In the case of 15 N2 -ABZ, the longlived spin order corresponds to the singlet order (SO) of a pair of N nuclei which is a population imbalance between their singlet state (total spin zero) and the triplet states (total spin one). Notably, earlier SABRE experiments showed the possibility of singlet order hyperpolarization in the cisconformation of 15 N2-ABZ. However, SO in cis-15 N2-ABZ does not exhibit the signs of extended lifetime, which is the result of the asymmetrical shape of the molecule, in contrast with the symmetric trans isomeric form which has molecular symmetry group of C2h. Meanwhile, coordination of trans-15 N2-ABZ with the SABRE complex is sterically hindered, making its direct hyperpolarization impossible.