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61.
Bacha PA Gruver HS Den Hartog BK Tamura SY Nutt RF 《Journal of chemical information and computer sciences》2002,42(5):1104-1111
A public bacterial mutagenicity database was classified into 2-D structural families using a set of specific algorithms and clustering techniques that find overlapping classes of compounds based upon chemical substructures. Structure-activity relationships were learned from the biological activity of the compounds within each class and used to identify rules that define substructures potentially responsible for mutagenic activity. In addition, this method of analysis was used to compare the pharmacologically relevant substructure of test compounds with their potential toxic substructures making this a potentially valuable in silico profiling tool for lead selection and optimization. 相似文献
62.
63.
Muhammad Rafiq Muhammad Khalid Muhammad Nawaz Tahir Muhammad Umair Ahmad Muhammad Usman Khan Muhammad Moazzam Naseer Ataualpa Albert Carmo Braga Shabbir Muhammad Zahid Shafiq 《应用有机金属化学》2019,33(11)
Present study advocates the joint experimental and computational studies of two potent benzoimidazole‐based hydrazones with chemical formula C23H18F2N4O ( 5a ) and C25H22FN5O3 ( 5b ). Both 5a and 5b were synthesized and resolved into their crystal structures using SC‐XRD for the assessment of bond lengths, bond angles, unit cells and space groups. The structures of 5a and 5b were chemically characterized using infrared (FT‐IR), UV–Visible, nuclear magnetic resonance (1H‐NMR and 13C‐NMR), EIMS and elemental analysis. DFT at M06‐2X/6‐31G(d,p) level of theory was performed to get optimized structures and countercheck the experimental findings. Overall, DFT findings show excellent concurrence with the experimental data which confirms the purity of both compounds. FMO, NBO analysis, MEP surfaces and nonlinear optical (NLO) properties were explored at same level of theory. UV–Vis analysis at TDDFT/M06‐2X/6‐31G(d,p) level of theory showed that 5b is red shifted with λmax 331.69 nm as compared to 5a with λmax 240.25 nm. Global reactivity parameters were estimated using energy of FMOs indicated the greater harness value than the softness values of 5a and 5b . NBO analysis confirmed that the presence of non‐covalent interactions, hydrogen bonding and hyper conjugative interactions are pivotal cause for the existence of 5a and 5b in the solid‐state. NLO results of 5a and 5b were observed better than standard molecule recommended the NLO activity of said molecules for optoelectronic applications. 相似文献
64.
Anwar Usman Ibrahim Abdul Razak Suchada Chantrapromma Sujit K. Ghorai Dipakranjan Mal Hoong‐Kun Fun Gur Dayal Nigam 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1118-1119
The title compound, C19H16O, crystallizes with two molecules of opposite chirality in the asymmetric unit. In both molecules, the naphthalene and cyclopentanone moieties are individually planar. The two cyclopentane rings adopt envelope conformations, while the cyclohexane ring adopts a boat conformation. 相似文献
65.
Usman Mohammad Smith Mark D. zur Loye Hans-Conrad 《Journal of chemical crystallography》2021,51(3):451-456
Journal of Chemical Crystallography - Deep blue, prism-shaped, X-ray diffraction quality single crystals of a new quaternary rubidium cobalt germanate, exact composition Rb2Co1.85Ge1.15O6, were... 相似文献
66.
67.
Muhammad Ramzan Saeed Ashraf Janjua Muhammad Haroon Riaz Hussain Muhammad Usman Muhammad Usman Khan Waqas Amber Gill 《International journal of quantum chemistry》2022,122(1):e26821
Organic photovoltaic solar cells are being designed to offer a low energy photovoltaic (PV) solution. Optimizing the molecular backbone is one the most important technique for improving the photovoltaic characteristic of A-D-A type small active layer molecules. Herein, we have designed and theoretical characterized six new molecules by end-capped and bridging core modifications of recently synthesized molecule BFHIC-4F. Enhancement in photovoltaic, optoelectronic and physio-chemical properties of newly designed molecules are seen by doing such modifications. Different advanced quantum chemical techniques have been employed to evaluate the performance of newly planned molecules. Large open circuit voltage and narrow band gap suggested that the designed molecules are efficient aspirants for solar cell applications. Moreover, maximum absorption capability in near-infra-red (NIR) region is observed for these newly designed molecules. To sum up, outcomes of all analyses advocated that the designed molecules are efficient candidates for solar cell applications. 相似文献
68.
Zhang Xuan-Jun Wu Jie-Ying Zhang Ming-Liang Tian Yu-Peng Jiang Min-Hua Usman Anwar Chantrapromma Suchada Fun Hoong-Kun 《Transition Metal Chemistry》2003,28(6):707-711
Two coordination polymers [Zn(Cabo)2(EtOH)2(4,4-Bipy)]
n
(1), and [Zn2(Cabo)2(NO3)2(4,4-Bipy)2]
n
(2) (Cabo = carbazolylacetate, 4,4-Bipy = 4,4-bipyridine) with chain and ladder structures, respectively, were prepared and characterized by X-ray single-crystal structural analysis. The results showed that the different anions of metal salts have a large effect on the construction of coordination frameworks. Both complexes show strong emissions in the solid state as well as high thermal stability. 相似文献
69.
R. Kieffer J. P. Hindermann R. El Bacha A. Kiennemann A. Deluzarche 《Reaction Kinetics and Catalysis Letters》1982,21(1-2):17-21
By chemical trapping, an acyl species has been evidenced in the oxidation of alcohols to carboxylate on an alumina surface. A possible reacton scheme is discussed.
. .相似文献
70.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Yan Zhang Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o543-o544
In the title compound, C24H17NO2S, the dioxine and thiazoline rings are distorted from planarity towards a half‐chair and an envelope conformation, respectively. The configurations of the dioxine ring, the thiazoline ring and the attached phenyl ring are conditioned by the sp3 state of the two bridgehead C atoms. The phenanthrene system is nearly coplanar with the dioxine ring, while the attached phenyl ring is orthogonal to the thiazoline ring. 相似文献