Crystal and molecular structure analysis of benzamide neuroleptics and analogs (VIII):endo- andexo-2,3-dimethoxy-N-[8-(phenylmethyl)-8-azabicyclo[3.2.1]oct-2-y1]-benzamide hydrochloride: C₂₃H₂₈N₂O3·HCl

Abstract

The crystal structures ofendo- andexo-2,3-dimethoxy-N-[8(phenylmethyl)-8-azabicyclo[3.2.1]oct-2-y1]benzamide hydrochloride have been determined by single-crystal X-ray diffraction techniques, and refined by full-matrix least squares. The endo-compound crystallizes in the monoclinic space groupP2₁/n witha=12.389(2) Å,b=22.861(3) Å,c=8.019(2) Å,β=93.58(2)°, andZ=4; the exo-compound crystallizes in the monoclinic space groupP2₁/a witha=26.295(12) Å,b=12.503(4) Å,c=6.667(7) Å,β=97.80(6)°, andZ=4. The calculated densities are 1.22 and 1.27 g cm⁻³ respectively. FinalR-factors are 0.04 for the endo and 0.05 for the exo-compound. Comparison with a very active analog, the tropapride, suggests that the lack of antipsychotic activity is due to a different orientation of the dimethoxyphenyl or carbonyl group for the exo- and endo-compound, respectively.