1-[4-(-D-Allopyranos­yloxy)benzyl­idene]semicarbazide hemihydrate

Acta Crystallographica Section E Structure Reports Online (Impact Factor: 0.35). 02/2010; 66(urn:issn:1600-5368). DOI: 10.1107/S1600536809055664/rz2403Isup2.hkl
Source: DOAJ


The molecule of the title compound, C14H19N3O7·0.5H2O, exhibits an E conformation about the C=N double bond. The water molecule possesses crystallographically imposed twofold symmetry. In the crystal structure, the molecules are connected by intermolecular O—H...O and N—H...O hydrogen bonds into a three-dimensional network.

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    ABSTRACT: The crystallographic problem: The production, and the visibility in the published literature, of thermal ellipsoid plots for small-molecule crystallographic studies remains an important method for assessing the quality of reported results. Since the mid 1960s, the program ORTEP (Johnson, 1965) has been perhaps the most popular computer program for generating thermal ellipsoid drawings for publication. The recently released update of ORTEP-III (Johnson & Burnett, 1996) has some additional features over the earlier versions, but still relies on fixed-format input files. Many users will find this very inconvenient, and will prefer to obtain drawings directly from their crystallographic coordinate files. This new version of ORTEP-3 for Windows provides all the facilities of ORTEP-III, but with a modern Graphical User Interface (GUI). Method of solution: A Microsoft-Windows GUI has been added to ORTEP-III. All the facilities of ORTEP-III are retained, and a number of extra features have been added. The GUI is effectively an editor that writes ORTEP-III input files, but the user need not have any knowledge of the inner workings of ORTEP. The main features of this program are: (i) ORTEP-3 for Windows can directly read many of the common crystallographic ASCII file formats. Currently supported formats are SHELX (Sheldrick, 1993), GX (Mallinson & Muir, 1985), GIF (Hall, Allen & Brown, 1991), SPF (Spek, 1990), CRYSTALS (Watkin, Prout, Carruthers & Betteridge, 1996), CSD-XR and CSD-FDAT. In addition, ORTEP-3 for Windows will accept any legal ORTEP-III instruction file. (ii) Covalent radii for the first 94 elements are stored internally, and may be modified by the user. All bonds are calculated automatically, and any individual bonds may be selected for removal, or for a special representation. (iii) The graphical representations of thermal ellipsoids for any element or selected sets of atoms can be individually set. All the possible graphical representations of thermal ellipsoids in ORTEP-III are also available in ORTEP-3 for Windows. (iv) A mouse labelling routine is provided by the GUI. Any number of selected atoms may be labelled, and any available Windows font may be used for the labels. The font attributes, e.g. italic, bold, colour, point size etc. can also be selected via a standard Windows dialog box. (v) As well as HPGL and PostScript Graphics graphic metafiles, it is also possible to get high quality graphics output by printing directly to an attached printer. The screen display may be saved as BMP or PCX format metafiles, and may also be copied to the clip-board for subsequent use by other Windows programs, e.g. word processing or graphics processing programs. Colour is available for all these output modes. (vi) A simple text editor is provided, so that input files may be modified without leaving the program. (vii) Symmetry expansion of the asymmetric unit to give complete connected fragments may be carried out automatically. (viii) Unit-cell packing diagrams are produced automatically. (ix) A number of options are provided to control the view direction. The molecular view may be rotated or translated by button commands from the tool bar, and views normal to crystallographic planes may also be obtained. Software environment and program specification: The program will read several common crystallographic file formats which hold information on the anisotropic displacement parameters. The operation of the program is carried out via standard self-explanatory MS-Windows menu items and dialog boxes. Hard-copy output is either by HPGL or Encapsulated PostScript metafiles, or by directly printing the graphics screen. Hardware environment: The program is implemented for IBM PC compatible computers running MS-Windows versions 3.1x, Windows 95 or Windows NT. At least a 486-66 machine is recommended with 8 Mbytes of RAM, and at least 5 Mbytes of disk space. Documentation and availability: The executable program, together with full documentation, is available free for academic users from http://www.chem.̃louis/ortep3. Although the program is written in Fortran77, a large number of nonstandard FTN77 calls are used to create the GUI. For this reason, the source code is not available.
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