Lomefloxacinium picrate

Abstract

In the cation of the title compound [systematic name: (RS)-4-(3-carboxy-1-ethyl-6,8-difluoro-4-oxo-1,4-dihydroquinolin-7-yl)-2-methylpiperazin-1-ium 2,4,6-trinitrophenolate], C17H20F2N3O3+·C6H2N3O7−, the piperazine ring adopts a slightly distorted chair conformation and contains a protonated N atom. An intramolecular O—H...O hydrogen bond occurs in the cation. The dihedral angles between the mean planes of the six-atom piperazine ring and the 10-atom fused ring system is 43.3 (5)°. The picrate anion interacts with the protonated N atom of an adjacent cation through a bifurcated N—H...(O,O) three-center hydrogen bond. Strong N—H...O hydrogen bonds in concert with weak π–π stacking interactions [centroid–centroid distance = 3.6460 (14) Å] dominate the crystal packing, creating a two-dimensional network structure along [011].