THE CRYSTAL AND MOLECULAR-STRUCTURE OF CHANDONIUM DIBROMIDE - A SYNTHETIC BISQUATERNARY AZA STEROIDAL NEUROMUSCULAR BLOCKING-AGENT

The crystal and molecular structure of a-methyl-3-pyrrolidino-17a-aza- D-homo-5-androstene dimethyl bromide (HS818, chandonium dibromide), C2 6H46N2Br2, has been determined crystallographically by the heavy atom method and refined by full-matrix least-squares calculations to R = 0. 074 for 5045 reflections. The compound crystallizes in space group P2( 1)2(1)2(1) with a = 6.468(2), b = 14.055(5), c = 28.216(11) angstrom. The N+ ... N+ inter-onium distance in chandonium bromide is 10.32 angs trom, close to the distance of 10.29 angstrom observed in chandonium i odide. Rings A, C, and D have a chair conformation and ring B is in a half-chair conformation. Ring E has a distorted envelope conformation. All rings in the steroid skeleton are trans-connected.