7-Chloro-6,8-dinitro-quinazolin-4(3H)-one acetic acid monosolvate

Crystal structures of 6-nitro-quinazolin-4(3H)-one, 6-amino-quinazolin-4(3H)-one and 4-amino-quinazoline hemi-hydro-chloride dihydrate

The title compounds, 6-nitro-quinazolin-4(3H)-one (C8H5N3O3; I), 6-amino-quinazolin-4(3H)-one (C8H7N3O; II) and 4-amino-quinazolin-1-ium chloride-4-amino-quinazoline-water (1/1/2), (C8H8N3 +·Cl-·C8H7N3·2H2O; III) were synthesized and their structures were determined by single-crystal X-ray analysis. In the crystals of I and II, the quinazoline mol-ecules form hydrogen-bonded dimers via N-H⋯O inter-actions. The dimers are connected by weak inter-molecular C-H⋯N and C-H⋯O hydrogen bonds, forming a layered structure in the case of I. In the crystal of II, N-H⋯N and C-H⋯O inter-actions link the dimers into a three-dimensional network structure. The asymmetric unit of III consists of two quinazoline mol-ecules, one of which is protonated, a chloride ion, and two water mol-ecules. The chloride anion and the water mol-ecules form hydrogen-bonded chains consisting of fused five-membered rings. The protonated and unprotonated quinazolin mol-ecules are linked to the chloride ions and water mol-ecules of the chain by their amino groups.