The high-resolution solid-state 13C NMR spectra of 2,6-dimethyl-3-nitroaniline, glycylglycine, glycyl- l-alanine, and trimethylimidazole, were obtained by a combination of cross-polarization and magic-angle spinning techniques (CP-MAS). The 13C NMR lines of the carbon atoms bonded to nitrogen in these compounds showed a characteristic line broadening or asymmetric doublet patterns. The theoretical lineshapes of the 13C NMR lines arising from the carbon atoms bonded to nitrogen were calculated using the adiabatic approximation since the rate of change of the Zeeman-quadrupole Hamiltonian of nitrogen nucleus is very slow when compared to the speed of the spinning sample holder in the MAS experiment. In the calculation, an asymmetric quadrupole coupling tensor of nitrogen nucleus was considered. It was found that the calculated lineshapes are in good agreement with the experimentally observed lineshapes, and that the 14N quadrupole coupling tensor was responsible for the lineshapes of the carbon atoms bonded to nitrogen. The sign of the quadrupole coupling constants of the nitro and amino nitrogens in 2,6-dimethyl-3-nitroaniline were determined to be negative from an analysis of the lineshapes. In the case of trimethylimidazole, it was found that the 13C NMR signals of the C 4 and C 5 carbon atoms could also be assigned from a comparison of the theoretical and experimental lineshapes. This resolution of the C 4 and C 5 NMR resonances was possible because of the freezing-out of the tautomerism involving the NH bonds.