Repository logo
 

Research Publications (Applied Sciences)

Permanent URI for this collectionhttp://ir-dev.dut.ac.za/handle/10321/213

Browse

Has files: YesSubject: search.filters.subject.Crystal structure

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Crystallography, molecular modeling, and COX-2 inhibition studies on indolizine derivatives
    (MDPI AG, 2021-06) Venugopala, Katharigatta N.; Chandrashekharappa, Sandeep; Tratrat, Christophe; Deb, Pran Kishore; Nagdeve, Rahul D.; Nayak, Susanta K.; Morsy, Mohamed A.; Borah, Pobitra; Mahomoodally, Fawzi M.; Mailavaram, Raghu Prasad; Attimarad, Mahesh; Aldhubiab, Bandar E.; Sreeharsha, Nagaraja; Nair, Anroop B.; Alwassil, Osama I.; Haroun, Michelyne; Mohanlall, Viresh; Shinu, Pottathil; Venugopala, Rashmi; Kandeel, Mahmoud; Nandeshwarappa, Belakatte P.; Ibrahim, Yasmine F.
    The cyclooxygenase-2 (COX-2) enzyme is an important target for drug discovery and development of novel anti-inflammatory agents. Selective COX-2 inhibitors have the advantage of reduced side-effects, which result from COX-1 inhibition that is usually observed with nonselective COX inhibitors. In this study, the design and synthesis of a new series of 7-methoxy indolizines as bioisostere indomethacin analogues (5a–e) were carried out and evaluated for COX-2 enzyme inhibition. All the compounds showed activity in micromolar ranges, and the compound diethyl 3-(4-cyanobenzoyl)-7-methoxyindolizine-1,2-dicarboxylate (5a) emerged as a promising COX-2 inhibitor with an IC50 of 5.84 µM, as compared to indomethacin (IC50 = 6.84 µM). The molecular modeling study of indolizines indicated that hydrophobic interactions were the major contribution to COX-2 inhibition. The title compound diethyl 3-(4-bromobenzoyl)-7-methoxyindolizine-1,2-dicarboxylate (5c) was subjected for single-crystal X-ray studies, Hirshfeld surface analysis, and energy framework calculations. The X-ray diffraction analysis showed that the molecule (5c) crystallizes in the monoclinic crystal system with space group P 21/n with a = 12.0497(6)Å, b = 17.8324(10)Å, c = 19.6052(11)Å, α = 90.000°, β = 100.372(1)°, γ = 90.000°, and V = 4143.8(4)Å3. In addition, with the help of Crystal Explorer software program using the B3LYP/6-31G(d, p) basis set, the theoretical calculation of the interaction and graphical representation of energy value was measured in the form of the energy framework in terms of coulombic, dispersion, and total energy.
  • Thumbnail Image
    Item
    International Union of Crystallography
    (Crystal structure of methyl 4-(4-hydroxyphenyl)-6- methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5- carboxylate monohydrate, 2016-08-19) Bairagi, Keshab M.; Venugopala, Katharigatta Narayanaswamy; Mondal, Pradip Kumar; Odhav, Bharti; Nayak, Susanta K.
    The title hydrate, C13H14N2O4H2O, crystallizes with two formula units in the asymmetric unit (Z0 = 2). The dihedral angles between the planes of the tetrahydropyrimidine ring and the 4-hydroxyphenyl ring and ester group are 86.78 (4) and 6.81 (6), respectively, for one molecule and 89.35 (4) and 3.02 (4) for the other. In the crystal, the organic molecules form a dimer, linked by a pair of N—HO hydrogen bonds. The hydroxy groups of the organic molecules donate O—HO hydrogen bonds to water molecules. Further, the hydroxy group accepts N—HO hydrogen bonds from amides whereas the water molecules donate O—HO hydrogen bonds to the both the amide and ester carbonyl groups. Other weak interactions, including C—HO, C—H and –, further consolidate the packing, generating a three-dimensional network.