(4,6-Diamino-1,3-phenyl-ene)bis-(phenyl-methanone).

In the mol-ecule of the title compound, C(20)H(16)N(2)O(2), two intra-molecular N-H⋯O inter-actions occur. The mol-ecular chains are linked by N-H⋯π and C-H⋯π inter-actions into a three-dimensional network, which seems to be very effective in the stabilization of the crystal structure.

5-[4-(1H-Imidazol-1-yl)phen-yl]-2H-tetra-zole dihydrate.

In the title compound, C(10)H(8)N(6)·2H(2)O, the central aromatic ring makes dihedral angles of 23.59 (15) and 16.99 (16)° with the terminal imidazole and tetra-zole rings, respectively, which are themselves almost coplanar [dihedral angle = 6.61 (18)°]. Two H atoms of the two water mol-ecules are half occupied. In the crystal packing, weak inter-molecular O-H⋯N, O-H⋯O and N-H⋯N hydrogen bonds and π-π stacking inter-actions [centroid-centroid distances of 3.73 (4) Šbetween benzene rings and 3.66 (3) Šbetween imidazole and tetra-zole rings] are observed.

Hexaaqua-zinc(II) 4,4'-(1,2-dihy-droxy-ethane-1,2-di-yl)dibenzoate monohydrate.

The title compound, [Zn(H(2)O)(6)](C(16)H(12)O(6))·H(2)O, consists of one 4,4'-(1,2-dihy-droxy-ethane-1,2-di-yl)dibenzoate anion lying on an inversion centre, one [Zn(H(2)O)(6)](2+) dication lying on a mirror plane and one solvent water mol-ecule located on a mirror plane. The octahedral [Zn(H(2)O)(6)](2+) cations, solvent water mol-ecules and anions inter-act via O-H⋯O hydrogen bonds, forming a three-dimensional network.

[µ-1,3-Bis(3,5-dimethyl-1H-pyrazol-1-yl-κN)propan-2-olato-κO:O]bis-[(ethanol-κO)zinc(II)] bis-(perchlorate).

In the centrosymmetric dinuclear title complex, [Zn(2)(C(13)H(19)N(4)O)(2)(C(2)H(5)OH)(2)](ClO(4))(2), the Zn(II) atom is in a distorted trigonal-bipyramidal coordination geometry. The equatorial plane is constructed by one N atom and one O atom from two 1,3-bis-(3,5-dimethyl-pyrazol-1-yl)propan-2-olate (bppo) ligands and one O atom from an ethanol mol-ecule. One N atom and one O atom from the two bppo ligands occupy the axial positions. Inter-molecular O-H⋯O hydrogen bonds between the ethanol mol-ecules and perchlorate anions, and O⋯π inter-actions between the perchlorate anions and pyrazole rings [O⋯centroid distances = 3.494 (3) and 3.413 (3) Å], lead to a chain structure along [010].