ABSTRACT
In the title mol-ecule, C7H6N4O3, the bicyclic ring system is planar with the carb-oxy-methyl group inclined by 81.05â (5)° to this plane. In the crystal, corrugated layers parallel to (010) are generated by N-Hâ¯O, O-Hâ¯N and C-Hâ¯O hydrogen-bonding inter-actions. The layers are associated through C-Hâ¯π(ring) inter-actions. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from Hâ¯O/Oâ¯H (34.8%), Hâ¯N/Nâ¯H (19.3%) and Hâ¯H (18.1%) inter-actions. The volume of the crystal voids and the percentage of free space were calculated to be 176.30â Å3 and 10.94%, showing that there is no large cavity in the crystal packing. Computational methods revealed O-Hâ¯N, N-Hâ¯O and C-Hâ¯O hydrogen-bonding energies of 76.3, 55.2, 32.8 and 19.1â kJâ mol-1, respectively. Evaluations of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated via dispersion energy contributions. Moreover, the optimized mol-ecular structure, using density functional theory (DFT) at the B3LYP/6-311G(d,p) level, was compared with the experimentally determined one. The HOMO-LUMO energy gap was determined and the mol-ecular electrostatic potential (MEP) surface was calculated at the B3LYP/6-31G level to predict sites for electrophilic and nucleophilic attacks.