Crystal and molecular structure of 1,1′-azo-2-phenylimidazo[1,2-a]-pyridinium dibromide: a new curariform agent

Abstract

The structure of the title compound, a powerful selective, neuromuscular blocking agent has been determined by a three-dimensional X-ray analysis. Crystals are monoclinic, space-group P2₁/c, with lattice parameters a=9·15(1), b= 12·05(1), c= 12·61(1)Å, β= 121·90(3)°, and Z= 2. The structure was solved by the heavy-atom method and refined by least-squares calculations to R 0·112 for 1698 reflections. The molecule consists of two identical halves joined by a 2-tetrazene link across a centre of symmetry. Phenyl rings are inclined at 47·5° to the rest of the molecule.