Ethyl 4-(tert-butylamino)-3-nitrobenzoate

Acta Crystallographica Section E Structure Reports Online (Impact Factor: 0.35). 01/2008; DOI: 10.1107/S160053680802206X/at2594Isup2.hkl
Source: DOAJ


In the title compound, C13H18N2O4, intramolecular N—H...O, N—H...N and C—H...O (× 3) hydrogen bonds generate S(6) and S(5) ring motifs. There are two crystallographically independent molecules (A and B) in the asymmetric unit. The nitro group is coplanar with the benzene ring, with O—N—C—C torsion angles of −0.33 (13) and 0.93 (14)° in molecules A and B, respectively. In the crystal structure, neighbouring molecules are linked together by intermolecular C—H...O hydrogen bonds. In addition, the crystal structure is stabilized by π–π interactions with centroid–centroid distances ranging from 3.7853 (6) to 3.8625 (6) Å.

Download full-text


Available from: Hasnah Osman, Oct 14, 2014
14 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: A series of 1,2-disubstituted benzimidazole-5(6)-carboxamides was prepared and evaluated in vitro for antimicrobial activity against Staphyloccus aureus, Escherichia coli and Candida albicans. The precursor benzimidazolecarboxylic acids 4a-c and 9a-c were prepared via oxidative condensation of diaminobenzoic acids with aldehydes and via several steps over the 2(1H)-benzimidazolones, respectively. All acids were converted to their acyl chlorides with SOCl2, then amidified with several N,N'-dialkylaminoethyl derivatives. Compounds 8a-c, 20 and 22 exhibited the best activity.
    Il Farmaco 07/1998; 53(6):415-20. DOI:10.1016/S0014-827X(98)00045-7
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: An account is given of the development of the SHELX system of computer programs from SHELX-76 to the present day. In addition to identifying useful innovations that have come into general use through their implementation in SHELX, a critical analysis is presented of the less-successful features, missed opportunities and desirable improvements for future releases of the software. An attempt is made to understand how a program originally designed for photographic intensity data, punched cards and computers over 10000 times slower than an average modern personal computer has managed to survive for so long. SHELXL is the most widely used program for small-molecule refinement and SHELXS and SHELXD are often employed for structure solution despite the availability of objectively superior programs. SHELXL also finds a niche for the refinement of macromolecules against high-resolution or twinned data; SHELXPRO acts as an interface for macromolecular applications. SHELXC, SHELXD and SHELXE are proving useful for the experimental phasing of macromolecules, especially because they are fast and robust and so are often employed in pipelines for high-throughput phasing. This paper could serve as a general literature citation when one or more of the open-source SHELX programs (and the Bruker AXS version SHELXTL) are employed in the course of a crystal-structure determination.
    Acta Crystallographica Section A Foundations of Crystallography 02/2008; 64(Pt 1):112-22. DOI:10.1107/S0108767307043930 · 2.31 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The results of a single-crystal structure determination when in CIF format can now be validated routinely by automatic procedures. In this way, many errors in published papers can be avoided. The validation software generates a set of evi‚„ƒ detailing issues to be addressed by the experimenter, author, referee and publication journal. Validation was pioneered by the IUCr journal Acta Crystallographica Section C and is currently standard procedure for structures submitted for publication in all IUCr journals. The implementation of validation procedures by other journals is in progress. This paper describes the concepts of validation and the classes of checks that are carried out by the program PLATON as part of the IUCr checkCIF facility. PLATON validation can be run at any stage of the structure re®nement, independent of the structure determination package used, and is recommended for use as a routine tool during or at least at the completion of every structure determination. Two examples are discussed where proper validation procedures could have avoided the publication of incorrect structures that had serious consequences for the chemistry involved.
    Journal of Applied Crystallography 02/2003; 36(1):7-13. DOI:10.1107/S0021889802022112 · 3.72 Impact Factor