2,2′-(Piperazine-1,4-di­yl)diacetonitrile

The complete mol­ecule of the title compound, C₈H₁₂N₄, is generated by a crystallographic inversion centre. The piperazine ring adopts a chair conformation with the N-bonded substituents in equatorial positions. In the crystal, mol­ecules are linked by C—H...N_c (c = cyanide) hydrogen bonds.

3-Meth­oxy-4-methyl-1H-1,2,4-triazol-5(4H)-one monohydrate

In the title hydrate, C₄H₇N₃O₂·H₂O, all the non-H atoms lie on a crystallographic mirror plane. The H atoms of both methyl groups are disordered over two sets of sites. In the crystal, N—H...O_w and O_w—H...O_k (w = water and k = ketone) hydrogen bonds link the components into (010) sheets.

4-[(2-Bromo­benzyl­idene)amino]-3-(pyridin-4-yl)-1H-1,2,4-triazole-5(4H)-thione

In the title compound, C₁₄H₁₀BrN₅S, the dihedral angle between the triazole ring and the pyridine and bromo­benzene rings are 26.42 (13) and 6.28 (13)°, respectively. The molecule exists as a thione in the solid state. In the crystal, mol­ecules are linked by N—H...N hydrogen bonds, generating [010] C(8) chains.