A supramolecular assembly dominated by N–H· · ·S hydrogen bonds: Structure of 2-thioureidobenzoxazole by single crystal X-ray diffraction

2-Thioureidobenzoxazole (1) was synthesized using 5-amino-3H-1,2,4-dithiazole-3-thione and 2-aminophenol and characterized by X-ray crystallography. The molecule of 1 is essentially planar due to p conjugation and an intramolecular N–H· · ·N hydrogen bond also contributes towards its planarity. The crystal lattice is built up of stacks of dimers of 1 generated by N–H· · ·S hydrogen bonds. The supramolecular assembly is dictated by weaker N–H· · ·S interactions to the exclusion of more stronger N–H· · ·X (X ¼ O, N) hydrogen bonds which are normally expected. q 2004 Elsevier B.V. All rights reserved.