Source
Instituut voor Farmaceutische, Wetenschappen, Katholieke Universiteit Leuven, Belgium.
Abstract
C16H22NO+2.Cl-, Mr = 295.808, monoclinic, P2(1), a = 11.967 (1), b = 12.529 (1), c = 9.9369 (9) A, beta = 93.00 (1) degrees, V = 1487.8 (2) A3, Z = 4, Dm = 1.32 (2), Dx = 1.321 Mg m-3, lambda(Cu K alpha) = 1.54178 A, mu(Cu K alpha) = 2.289 mm-1, F(000) = 632, T = 291 K, final R = 0.040 for 2448 observed reflections. The two molecules present in the asymmetric unit are linked by an extensive network of hydrogen bonds, including several of the less common (C-)H...O and (C-)-H...Cl types. This interpretation is substantiated by a Mulliken population analysis resulting from CNDO/2 calculations. The major effect of the presence of the epoxyethano bridge is a marked flattening about the N atom of the piperidinium ring. Whether this is sufficient to explain the inactivity of the compound at the opioid kappa receptor is not clear.