Molecular structures of two copper complexes with the pharmaceuticals norfloxacin and tinidazole, when powder X-ray diffraction assists multi-domain single-crystal X-ray diffraction.

The crystal structures of bis[1-ethyl-6-fluoro-4-oxo-7-(piperazin-1-ium-4-yl)-1,4-dihydroquinoline-3-carboxylato]copper(II) sulfate heptahydrate, [Cu(C16H18FN3O3)2]SO4·7H2O or [Cu(nor)2]SO4·7H2O (nor is norfloxacin), and bis{1-[2-(ethylsulfonyl)ethyl]-2-methyl-5-nitroimide}dinitratocopper(II), [Cu(NO3)2(C8H13N3O4S)2] or [Cu(NO3)2(tnz)2] (tnz is tinidazole), were solved by X-ray diffraction. Both complexes crystallize in the space group P21/c, with Z = 4 (for nor) and Z = 2 (for ntz) molecules per unit cell. In [Cu(nor)2]SO4·7H2O, the CuII ion is at the centre of a square-planar environment, trans coordinated to two independent norfloxacin molecules in the zwitterionic form acting as bidentate ligands through one of the carboxyl (cbx) and the carbonyl (cb) O atoms. The solid is further stabilized by an extensive network of N-H...O(sulfate), N-H...O(cbx), N-H...OW, OW-H...O(sulfate) and OW-H...OW hydrogen bonds. The [Cu(NO3)2(tnz)2] complex is centrosymmetric, with the CuII ion in a square planar environment, coordinated to a tinidazole molecule acting as a monodentate ligand through its imidazole N atom and to one nitrate O atom. The vibrational FT-IR absorption spectra and thermal behaviour of the complexes were also studied and are briefly discussed based on the crystal structures.

Molecular structure of 4-hidroxy-3-(3-methyl-2-butenyl) acetophenone, a plant antifungal, by X-ray diffraction, DFT calculation, and NMR and FTIR spectroscopy.

The molecular structure of two mixed and closely related conformers of the title compound, C13H16O2, found in the solid with unequal occupancies has been determined by X-ray diffraction methods. The substance crystallizes in the monoclinic Pca2(1) space group with a=17.279(2), b=5.1716(7), c=12.549(2)Å, and Z=4 molecules per unit cell. The structure was solved from 1314 reflections with I>2σI and refined to an agreement R1-factor of 0.049. The minor conformer (34.7%) is nearly mirror-related to and extensively overlapped with the major one. The skeleton of the 4-hydroxyacetophenone molecular fragment and the prenyl group, (CH2)(CH)C(CH3)2, pendant arm attached to it are both planar and perpendicular to each other. A strong intermolecular O-H⋯O bond links neighboring molecules in the lattice to produce a polymeric structure. The conformational structures of the compound in the gas phase have been calculated by the DFT method and the geometrical results have been compared with the X-ray data. These data allow a complete assignment of vibration modes in the solid state FTIR and Raman spectra. The calculated 1H and 13C chemicals shifts are in good agreement with the corresponding experimental NMR spectra of the compound in solution.