Crystal structure of N-(p-bromophenylcarbamoyl)thiamine anhydride (N,S-cis-type)

Abstract

The crystal structure of the title compound has been determined by three-dimensional X-ray analysis. The crystals are monoclinic, a=8·736, b= 11·668, c= 20·451 Å, β= 99° 21′, Z= 4, space group P2₁/c. The structure was solved from diffractometer data by Patterson, Fourier, and refined by least-squares methods, to R 0·065 for 2583 independent observed reflections. The overall shape of the molecule was closely similar to that found in the N,S-trans-type molecule, but the configuration of the thiacyclobutane ring is significantly twisted, in contrast with the planar N,S-trans type. The thiacyclobutane ring is slightly puckered with a dihedral angle of ca. 175°.