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排序方式: 共有244条查询结果,搜索用时 46 毫秒
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Sajjad H. Sumrra Abrar U. Hassan Muhammad Imran Muhammad Khalid Ehsan U. Mughal Muhammad N. Zafar Muhammad N. Tahir Muhammad A. Raza Ataualpa A.C. Braga 《应用有机金属化学》2020,34(7):e5623
This study reports the synthesis of sulfonamide-derived Schiff bases as ligands L 1 and L 2 as well as their transition metal complexes [VO(IV), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II)]. The Schiff bases (4-{E-[(2-hydroxy-3-methoxyphenyl)methylidene]amino}benzene-1-sulfonamide ( L 1 ) and 4-{[(2-hydroxy-3-methoxyphenyl)methylidene]amino}-N-(5-methyl-1,2-oxazol-3-yl)benzene-1-sulfonamide ( L 2 ) were synthesized by the condensation reaction of 4-aminobenzene-1-sulfonamide and 4-amino-N-(3-methyl-2,3-dihydro-1,2-oxazol-5-yl)benzene-1-sulfonamide with 2-hydroxy-3-methoxybenzaldehyde in an equimolar ratio. Sulfonamide core ligands behaved as bidentate ligands and coordinated with transition metals via nitrogen of azomethine and the oxygen of the hydroxyl group. Ligand L 1 was recovered in its crystalline form and was analyzed by single-crystal X-ray diffraction technique which held monoclinic crystal system with space group (P21/c). The structures of the ligands L 1 and L 2 and their transition metal complexes were established by their physical (melting point, color, yields, solubility, magnetic susceptibility, and conductance measurements), spectral (UV–visible [UV–Vis], Fourier transform infrared spectroscopy, 1H NMR, 13C NMR, and mass analysis), and analytical (CHN analysis) techniques. Furthermore, computational analysis (vibrational bands, frontier molecular orbitals (FMOs), and natural bonding orbitals [NBOs]) were performed for ligands through density functional theory utilizing B3LYP/6-311+G(d,p) level and UV–Vis analysis was carried out by time-dependent density functional theory. Theoretical spectroscopic data were in line with the experimental spectroscopic data. NBO analysis confirmed the extraordinary stability of the ligands in their conjugative interactions. Global reactivity parameters computed from the FMO energies indicated the ligands were bioactive by nature. These procedures ensured the charge transfer phenomenon for the ligands and reasonable relevance was established with experimental results. The synthesized compounds were screened for antimicrobial activities against bacterial (Streptococcus aureus, Bacillus subtilis, Eshcheria coli, and Klebsiella pneomoniae) species and fungal (Aspergillus niger and Aspergillus flavous) strains. A further assay was designed for screening of their antioxidant activities (2,2-diphenyl-1-picrylhydrazine radical scavenging activity, total phenolic contents, and total iron reducing power) and enzyme inhibition properties (amylase, protease, acetylcholinesterase, and butyrylcholinesterase). The substantial results of these activities proved the ligands and their transition metal complexes to be bioactive in their nature. 相似文献
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Rabail Ujan Pervaiz Ali Channar Aamer Saeed Qamar Abbas Hummera Rafique Saba Ashraf Mahboob Ali Rind Abbas Hassan Anwar Ul-Hamid Mubashar Hassan Hussain Raza Sung-Yum Seo 《Journal of heterocyclic chemistry》2021,58(10):1929-1935
The porcine pancreatic elastase inhibition and free-radical scavenging play a crucial role in age progression. All the series of 10 newly synthesized benzimidazole thioureas ( 4a-j ) were assessed for elastase inhibition and radical scavenging activity to identify the suitable anti-aging ingredient for cosmetics products. The compounds 4e , 4f , 4g , and 4h showed inhibition better than the standard, while compound 4f showed the most significant elastase inhibition with the IC50 value of 1.318 ± 0.025 μM compared with oleanic acid IC50 13.451 ± 0.014 used ±1.989 and 41.563 ± 0.824, respectively, as standard. Molecular docking studies were performed and the compound 4f showed binding energy of 7.2 kcal/mol. Kinetics studies revealed inhibition of the pancreatic elastase in a competitive manner. The relative binding energy and structure activity relationship (SAR) identified compound 4f as an effective inhibitor of porcine pancreatic elastase. Compounds 4e and 4i showed remarkable free-radical scavenging activity with SC50 values of 26.421. 相似文献
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Farhan M. Khan Muhammad A. Abbasi Aziz-ur-Rehman Sabahat Z. Siddiqui Abdul R. Sadiq Butt Hussain Raza Ayesha Zafar Syed A. Ali Shah Muhammad Shahid Sung-Yum Seo 《Journal of heterocyclic chemistry》2021,58(5):1089-1103
By using a convergent methodology, a novel series of N-arylated 4-yl-benzamides containing a bi-heterocyclic thiazole–triazole core was synthesized, and the structures of these hybrid molecules, 9a–k , were corroborated through spectral analyses. The in vitro studies of these multifunctional molecules demonstrated their potent carbonic anhydrase inhibition relative to the standard used. The kinetics mechanism was exposed by Lineweaver–Burk plots, which revealed that 9j inhibited carbonic anhydrase non-competitively by forming an enzyme-inhibitor complex. The inhibition constants Ki calculated from Dixon plots for this compound was 1.2 μM. The computational study was also persuasive with the experimental results, and these molecules disclosed good results of all scoring functions and interactions, which suggested a good binding to carbonic anhydrase. So, it was predicted from the inferred results that these molecules might be considered as promising medicinal scaffolds for various diseases related to the uncontrolled production of this enzyme. 相似文献
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Iqbal Saeed Raza Aadil Butt Muhammad Fasih Uddin Mirza Jawad Iqbal Muhammad Ghafoor Salman El-Hajjar Mohammed 《Optical Review》2021,28(3):278-288
Optical Review - In this paper, we propose a full duplex architecture based on a hybrid link composed of free space optics (FSO) and multimode plastic optical fiber (MMPOF) for short-range wireless... 相似文献
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Nonlinear Dynamics - In recent years, substantial work has been done for developing image encryption algorithms. Image encryption requires handling of large data, which needs computationally... 相似文献
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M. Kameswara Rao M. Sharma S. K. Raza D. K. Jaiswal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):559-566
The synthetic standards for cysteine and valine adducts of sulphur mustard have been synthesized using 2-(2-chloroethylthio) ethanol (half-mustard). These adducts have been recognized as biomarkers for exposure to sulphur mustard. The adducts have been fully characterized using 1 H and 13 C NMR spectroscopy and mass spectrometric techniques. 相似文献
10.
Shefali Saxena M. Palit Purnanand S. K. Raza 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):247-253
Abstract A series of structurally related unsymmetrically substituted methylphosphonate diesters have been synthesised and subjected to electron impact (El) mass spectral studies. These studies though aimed at total identification of the compounds, resulted in certain interesting observations and hence are being reported. In order to confirm the observations under electron impact and to support the mechanism of fragmentation we have also performed MSNS experiments in both daughter ion and parent ion modes. 相似文献