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101.
Sundas Mumtaz Shahid Iqbal Mazloom Shah Rafaqat Hussain Fazal Rahim Wajid Rehman Shoaib Khan Obaid-ur-Rahman Abid Liaqat Rasheed Ayed A. Dera Hanan A. Al-ghulikah Sana Kehili Eslam B. Elkaeed Hamad Alrbyawi Mohammed Issa Alahmdi 《Molecules (Basel, Switzerland)》2022,27(19)
Twenty-four analogs based on triazinoindole bearing benzimidazole/benzoxazole moieties (1–25) were synthesized. Utilizing a variety of spectroscopic methods, including 1H-, 13C-NMR, and HREI-MS, the newly afforded compounds (1–25) were analyzed. The synthesized analogs were tested against urease enzyme (in vitro) as compared to the standard thiourea drug. All triazinoindole-based benzimidazole/benzoxazole analogs (1–25) exhibited moderate to excellent inhibition profiles, having IC50 values of 0.20 ± 0.01 to 36.20 ± 0.70 μM when evaluated under the positive control of thiourea as a standard drug. To better understand the structure–activity relationship, the synthesized compounds were split into two groups, “A” and “B.” Among category “A” analogs, analogs 8 (bearing tri-hydroxy substitutions at the 2,4,6-position of aryl ring C) and 5 (bearing di-hydroxy substitutions at the 3,4-position of aryl ring C) emerged as the most potent inhibitors of urease enzyme and displayed many times more potency than a standard thiourea drug. Besides that, analog 22 (which holds di-hydroxy substitutions at the 2,3-position of the aryl ring) and analog 23 (bearing ortho-fluoro substitution) showed ten-fold-enhanced inhibitory potential compared to standard thiourea among category “B” analogs. Molecular docking studies on the active analogs of each category were performed; the results obtained revealed that the presence of hydroxy and fluoro-substitutions on different positions of aryl ring C play a pivotal role in binding interactions with the active site of the targeted urease enzyme. 相似文献
102.
Rafiq Shahid Abbas Zaheer Nawaz Muhammad Alharbi Sayer Obaid 《Journal of Thermal Analysis and Calorimetry》2021,145(6):3269-3279
Journal of Thermal Analysis and Calorimetry - A numerical model is developed to study the effects of temperature-dependent viscosity on heat transfer in magnetohydrodynamic flow of micropolar fluid... 相似文献
103.
Imtiaz Maria Shahid Fiza Hayat Tasawar Alsaedi Ahmed 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2461-2470
Journal of Thermal Analysis and Calorimetry - The present paper explores non-Fourier heat flux theory for Jeffrey fluid flow subject to a rotating disk. The current analysis is executed in the... 相似文献
104.
Semi-empirical formulae for ground state Λ-binding energy of heavy hypernuclei, in inverse powers of the mass number, using
the mass distribution in the folding model, under fairly reasonable assumptions about the range of the Λ-nucleon force are
obtained in more than one plausible way. However, they are found to give nearly identical results. A reasonable estimate of
the Λ well-depth is obtained from a chi-square fit of the available ground state Λ-binding energy data of medium and heavy
nuclei. 相似文献
105.
We propose a method to measure the photon statistics of a quantized radiation field in an electromagnetically induced transparency setup. The proposed method provides a direct way of measuring the photon statistics. This method is insensitive to the detector efficiency. 相似文献
106.
Hafiz Ghulam Abbas Saeeda Asghar Maqbool Ahmad Shahid 《Journal of Radioanalytical and Nuclear Chemistry》1995,189(1):45-50
A method for labeling of anti-carcinoembryonic antigen (CEA) monoclonal antibody (MAb) BW 431/26 is described. For preparations of99mTc-anti-CEA complex, a solution (1 ml) of tetrasodium-1,1,3,3-propanetetetraphosphate dihydrate (2.7 mg), stannous chloride dihydrate (0.12 mg) and sodium chloride (0.2 mg) in 5 ml of 0.9% saline was added to a vial containing monoclonal antibody (2 mg) from mouse (MAb BW 431/26), D-glucitol (2 mg) and sodium sulfate (2 mg) to obtain a clear solution. A quantitative labeling yield of the MAb BW 431/26 was achieved by addition of 5 ml (40.5 mCi, 1.5 Gbq) technetium-99m-pertechnetate (99mTcO4) generator eluate at room temperature within 10 minutes. The radiochemical purity determined by ITLC (Gelman, SG) plates was >95%. 相似文献
107.
In world, many people struggle with viral, parasitic, bacterial, cancer, and other diseases. Therefore, numerous chemists seek to develop less toxic, more selective, and effective medicines. Most therapeutic medicines are based on inhibition of specific enzymes. Acridines are interesting heterocyclic structures that are much sought after targets attributed to their wide biological activities and feature to display potent enzymes inhibitory effects. Their approach of action is owing to DNA interaction and subsequent effects on the biological functions linked to DNA and associated enzymes. In this regards, we synthesized acridine analogous through 1,4-diazabicyclo[2.2.2]octane (DABCO)–polyethylene glycol-400 (PEG-400) mediated ionic liquid approach. DABCO–PEG-400-mediated IL was prepared through the DABCO alkylation using 1-bromopentane followed by mixing with PEG-400. The synthesized analogous were investigated as inhibitors of alkaline phosphatase, which is a nonspecific phosphomonoester hydrolase that catalyzes the hydrolysis of broad spectrum of organic monophosphates. Analogue viz. 3,3,6,6-tetramethyl-9-(4-nitrophenyl)-2,3,4,5,6,7,9,10-octahydroacridine-1,8-dione was found to be potent alkaline phosphatase inhibitor. 相似文献
108.
Guangfu Wang Lixia Yan Shahid Zaman Minjie Zhang 《International journal of quantum chemistry》2020,120(18):e26334
The connective eccentricity index (CEI) of a graph G is defined as , where εG(.) denotes the eccentricity of the corresponding vertex. The CEI obligates an influential ability, which is due to its estimating pharmaceutical properties. In this paper, we first characterize the extremal graphs with respect to the CEI among k-connected graphs (k-connected bipartite graphs) with a given diameter. Then, the sharp upper bound on the CEI of graphs with given connectivity and minimum degree (independence number) is determined. Finally, we calculate the CEI of two sets of molecular graphs: octane isomers and benzenoid hydrocarbons. We compare their CEI with some other distance-based topological indices through their correlations with the chemical properties. The linear model for the CEI is better than or as good as the models corresponding to the other distance-based indices. 相似文献
109.
Pyrolysis has the potential of transforming used tyres into useful recyclable products. Pyrolytic carbon black is one of the most important products of tyre pyrolysis. Waste tyres were pyrolysed at 450 °C in a batch reactor under atmospheric pressure. The recovered pyrolytic carbon black residues were studied to investigate their characteristics for use as a possible adsorbent. EDX elemental analysis and surface area determinations were used to investigate the distinctive features of pyrolytic carbon black. Due to various inorganic additives of the original tyre that contaminated the carbon black obtained, it was treated with acid for demineralization. The demineralized carbon black was activated at 900 °C in a furnace. It was observed that acid treatment and activation increased the surface areas and decreased the concentration of contaminants. Furthermore, adsorption characteristics of methylene blue on acid‐treated and activated carbon black (prepared via acid treatment) were compared with those of commercial activated carbon in liquid phase adsorption. It was found that adsorption capacity of methylene blue on acid‐treated activated carbon black was greater. 相似文献
110.
M. H. Hashmi Abdus Subhan Adil N. A. Chughtai Farhat Rafique Chughtai M. A. Shahid 《Mikrochimica acta》1968,56(2):291-296
Summary A method has been developed for the separation and identification of 20 common amino acids by circular thin-layer chromatography. The amino acids are separated to neutral, acid, and basic groups by electrolysis and then identified by circular TLC. The method is simple and development of a chromatoplate is complete in about 3 minutes. The application of the method is illustrated by the analysis of amino acids in foods and in urine.
Zusammenfassung Zur Trennung und Identifizierung 20 gewöhnlicher Aminosäuren wurde ein chromatographisches Verfahren entwickelt. Die Aminosäuren werden elektrolytisch in neutrale, basische und saure getrennt und dann auf kreisförmiger Dünnschichte chromatographiert. Die Entwicklung des Chromatogramms ist in 3 Minuten beendet. Die Anwendung zur Analyse von Lebensmitteln und Harn wird beschrieben.相似文献