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1.
Dr. Safaa M. Kishk Dr. Kirsty J. McLean Dr. Sakshi Sood Darren Smith Jack W.D. Evans Prof. Mohamed A. Helal Prof. Mohamed S. Gomaa Prof. Ismail Salama Prof. Samia M. Mostafa Dr. Luiz Pedro S. de Carvalho Colin W. Levy Prof. Andrew W. Munro Dr. Claire Simons 《ChemistryOpen》2019,8(7):995-1011
The emergence of untreatable drug-resistant strains of Mycobacterium tuberculosis is a major public health problem worldwide, and the identification of new efficient treatments is urgently needed. Mycobacterium tuberculosis cytochrome P450 CYP121A1 is a promising drug target for the treatment of tuberculosis owing to its essential role in mycobacterial growth. Using a rational approach, which includes molecular modelling studies, three series of azole pyrazole derivatives were designed through two synthetic pathways. The synthesized compounds were biologically evaluated for their inhibitory activity towards M. tuberculosis and their protein binding affinity (KD). Series 3 biarylpyrazole imidazole derivatives were the most effective with the isobutyl ( 10 f ) and tert-butyl ( 10 g ) compounds displaying optimal activity (MIC 1.562 μg/mL, KD 0.22 μM ( 10 f ) and 4.81 μM ( 10 g )). The spectroscopic data showed that all the synthesised compounds produced a type II red shift of the heme Soret band indicating either direct binding to heme iron or (where less extensive Soret shifts are observed) putative indirect binding via an interstitial water molecule. Evaluation of biological and physicochemical properties identified the following as requirements for activity: LogP >4, H-bond acceptors/H-bond donors 4/0, number of rotatable bonds 5–6, molecular volume >340 Å3, topological polar surface area <40 Å2. 相似文献
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Mehfooz Haroon Saeed Aamer Faisal Muhammad Larik Fayaz Ali Muqadar Urooj Khatoon Saira Channar Pervaiz Ali Ismail Hammad Bilquees Salma Rashid Sajid Shafique Shagufta Mirza Bushra Dilshad Erum Ahmad Fawad 《Research on Chemical Intermediates》2020,46(5):2437-2456
Research on Chemical Intermediates - Meldrum’s acid derivatives were facile synthesized by one-pot condensation process and characterized by NMR (1H, 13C, DEPT-90 and DEPT-135) and EI-MS. The... 相似文献
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New thiazole derivatives were synthesized and fully characterized, then coordinated with PtCl4 salt. Also, the newly synthesized Pt(IV) complexes were investigated analytically (elemental and thermogravimetric analyses), spectrally (infrared, UV–visible, mass, 1H NMR, 13C NMR, X‐ray diffraction) as well as theoretically (kinetics, modeling and docking). The data extracted led to the establishment of the best chemical and structural forms. Octahedral geometry was the only formula proposed for all complexes, which is favorable for d6 systems. The molecular ion peaks from mass spectral analysis coincide with all analytical data, confirming the molecular formula proposed. X‐ray diffraction (XRD) and scanning electron microscopy (SEM) allowed discrimination of features between crystalline particles and other amorphous morphology. By applying Gaussian09 as well as HyperChem 8.2 programs, the best structural forms were obtained, as well as computed significant parameters. Computed parameters such as softness, hardness, surface area and reactivity led us towards application in two opposing pathways: tumor inhibition and oxidation activation. The catalytic oxidation for CO was conducted over PtO2, which was yielded from calcination of the most reactive complex. The success of catalytic role for synthesized PtO2 was due to its particulate size and surface morphology, which were estimated from XRD patterns and SEM images, respectively. The antitumor activity was tested versus HCT‐116 and HepG‐2 cell lines. Mild toxicity was recorded for two of the derivatives and their corresponding complexes. This degree of toxicity is more favorable in most cases, due to exclusion of serious side effects, which is coherently attached with known antitumor drugs. 相似文献
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Moustafa A. H. El-Sayed H. A. El Rayes S. M. Morsy H. A. Abd-allah S. H. Ismail H. F. Abd El-Aal M. M. 《Russian Journal of General Chemistry》2019,89(11):2314-2320
New pyrazole and pyridine derivatives have been synthesized from sulfanilamide and phenazone via diazotization and coupling with a wide range of α-CH acids followed by heterocyclization with hydrazine derivative, hydroxylamine and cyanoacetamide. The antimicrobial tests of the products demonstrate high to moderate activity against Gram (?ve) bacteria and the tested fungi. No positive action of the products is observed against Gram (+ve) bacteria.
相似文献6.
Structural Chemistry - Metal carbonyl complexes, which have been known as effective catalysts since early days, find use in many fields both directly and indirectly. Although the use of metal... 相似文献
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Topcuoglu Bulent Ozmen Suleyman Fatih Boztosun Ismail Gulludag Cevdet Bertan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):783-797
Journal of Radioanalytical and Nuclear Chemistry - In this study, natural (226Ra, 232Th, 40K) and artificial (137Cs) radionuclide activity concentration levels of 63 greenhouse soils collected from... 相似文献
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Brahim Khemaies Rouissi Khalil Soussi-Baatout Amira Khattech Ismail 《Journal of Thermal Analysis and Calorimetry》2021,143(4):3173-3179
Journal of Thermal Analysis and Calorimetry - The thermochemical and kinetic studies of diammonium hydrogen phosphate precipitation in phosphoric acid with ammonia were followed using a... 相似文献
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