Crystal structure of 1-[(2,2-dimethyl-1,3-dioxolan-4-yl)meth-yl]-2-(thia-zol-4-yl)-1H-benzimidazole.

The benzimidazole ring in the title compound, C16H17N3O2S, is almost planar, with the greatest deviation from the mean plane being 0.032 (1) Å. The fused-ring system makes dihedral angles of 19.91 (7) and 24.51 (8)° with the best plane through each of the thia-zol-4-yl and 1,3-dioxolan-4-yl rings, respectively; the latter exhibits an envelope conformation with the methyl-ene C atom being the flap. Finally, the thia-zol-4-yl ring makes a dihedral angle of 33.85 (9)° with the 1,3-dioxolan-4-yl ring. In the crystal, mol-ecules are connected by a pair of C-H⋯π(imidazole) inter-actions to form centrosymmetric aggregates.

Bis[1-benzyl-2-(1,3-thia-zol-4-yl)-1H-benzimidazole-κ(2) N (2),N (3)]dichloridocobalt(II).

In the title compound, [CoCl2(C17H13N3S)2], the Co(II) atom exhibits a distorted octa-hedral coordination geometry involving two chloride ligands, one of which is split over two positions [refined site-occupancy ratio = 0.847 (18):0.153 (18)], and four N-atom donors from two 1-benzyl-2-(1,3-thia-zol-4-yl)-1H-benzimidazole ligands. The two chelate rings including the Co(II) atom are essentially planar, the maximum deviations from the mean planes being 0.080 (2) and 0.046 (2) Å; the dihedral angle between them is 74.1 (1)°. In both ligands, the thia-zole and benzimidazole rings are nearly coplanar, as indicated by the dihedral angles between their planes of 1.16 (8) and 6.29 (7)°. Each pendant benzene ring is almost perpendicular to the benzimidazole mol-ecule to which it is attached; the dihedral angles between their planes are 75.94 (9) and 75.55 (10)°. The crystal structure is stabilized by non-classical C-H⋯Cl hydrogen bonding forming a three-dimensional network.

Ethyl 2-(2-amino-5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7-yl)acetate.

The nine-membered fused-ring of the title compound, C(10)H(13)N(5)O(2), is approximately planar [maximum deviation = 0.012 (1) Å]; the bond angle at the methylene C atom is 111.33 (10)°. In the crystal, the amino group forms hydrogen bonds to the N atoms of the triazole rings of adjacent mol-ecules, generating a ribbon running along the a axis.