Bis(benzyl-tri-methyl-ammonium) bis-[(4SR,12SR,18RS,26RS)-4,18,26-trihy-droxy-12-oxido-13,17-dioxahepta-cyclo-[14.10.0.0(3,14).0(4,12).0(6,11).0(18,26).0(19,24)]hexa-cosa-1,3(14),6,8,10,15,19,21,23-nona-ene-5,25-dione] sesquihydrate: dimeric structure formation via [O-H-O](-) negative charge-assisted hydrogen bonds (-CAHB) with benzyl-tri-methyl-ammonium counter-ions

The reaction between bis-ninhydrin resorcinol and benzyl-tri-methyl-ammonium fluoride in ethanol has produced the title compound, 2C10H16N(+)·2C24H13O8 (-)·1.5H2O, which contains a unique centrosymmetric supra-molecular dimeric entity, where two deprotonated ligands are held together via two strong and short [O⋯O = 2.4395 (13) Å] [O-H-O](-) bonds of the type negative charge-assisted hydrogen bonds (-CAHB). The central aromatic rings of the ligands create parallel-displaced π-π stacking at an inter-planar distance of 3.381 (1) Å, which helps stabilize the dimer. In the crystal, two symmetry-related solvent water mol-ecules with a site occupancy of 0.75 are attached to the carbonyl groups of the dimer by weaker O-H⋯O hydrogen bonds, forming chains along [101].