Crystal structures of mefloquine-oxazolidine derivatives, 4-[3-(halophenyl)hexahydro[1,3]oxazolo[3,4-a]pyridin-l-yl]-2,8-bis(trifluoromethyl)quinolines

摘要

Crystal structures are reported for five racemic 4-{3-(halophenyl)hexahydro[1,3]oxazolo[3,4-a]pyridin-l-yl}-2,8-bis(trifluoromethyl)quinolines, 2, namely (2: X = 2-F, 3-Br, 4-C1, 4-Br and 4-F), prepared from mefloquine and XC6H5CHO. In each case, the compound crystallizes in the triclinic space group, PI, with Z = 2. All molecules have "F" shapes with the X-phenyl and quinoline rings lying on one side of the best plane through the fused oxa-zolidine-piperidine rings. Differences in the conformations of the molecules are indicated by the differences in the interplanar angles. In each case, the supramolecular arrangements are made up from combinations of π ? ? ? π and some of C-H ? ? ? X and C-X? ? ? π (X = halo) interactions. Two similar structural sub-sets found in the crystal structures of the five derivatives are centro symmetric π ? ? ? π-linked dimers and centrosymmetric cage-like dimers. The cage-like dimers, formed by the intermeshing of the rings of the monomers, are generated from different weak intermolecular interactions, which include C-H ? ? ? X and C-X ? ? ? π (X = halo) interactions. Comparisons are made between the activities of the mefloquine-oxazolidine derivatives in in-vitro tests against the multidrug-resistant tuberculosis strain and conformations, as measured by interplanar angles.