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991.
Singh SK Vobbalareddy S Kalleda SR Rajjak SA Casturi SR Datla SR Mamidi RN Mullangi R Bhamidipati R Ramanujam R Akella V Yeleswarapu KR 《Organic & biomolecular chemistry》2004,2(17):2442-2450
Analogs of 1,5-diarylpyrazoles with a novel pharmacophore at N1 were designed, synthesized and evaluated for the in-vitro cyclooxygenase (COX-1/COX-2) inhibitory activity. The variations at/around position-4 of the C-5 phenyl ring in conjunction with a CF3 and CHF2 groups at C-3 exhibited a high degree of potency and selectivity index (SI) for COX-2 inhibition. The in-vivo evaluation of these potent compounds with a few earlier ones indicated the 4-OMe-phenyl analog and the 4-NHMe-phenyl analog with a CF3, and the 4-OEt-phenyl analog with a CHF2 group at C-3 to possess superior potency than celecoxib. In addition to its impressive anti-inflammatory, antipyretic, analgesic and anti-arthritic properties, compound (DRF-4367) was found to possess an excellent pharmacokinetic profile, gastrointestinal (GI) safety in the long-term arthritis study and COX-2 potency in human whole blood assay. Thus, compound was selected as an orally active anti-inflammatory candidate for pre-clinical evaluation. 相似文献
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Megat Harun Al Rashid Megat Ahmad Abdul Aziz Mohamed Che Seman Mahmood Rafhayudi Jamro Muhammad Rawi Muhammad Zin 《Journal of Physics and Chemistry of Solids》2007,68(12):2349-2352
Nanocrystalline alumina powder was produced from calcinations of Al13-oxalate precipitates at 1100 °C. A nearly normal distribution of agglomerated alumina powder was obtained with an average particle size of about 1 μm. XRD measurement confirmed that the alumina produced was of high purity and crystalline α-phase. Microstructural features of both the precipitates and alumina obtained were studied using the small angle neutron scattering (SANS) technique. SANS examinations show the formation of microstructures in the alumina powder of mass fractals type with dimension of ∼2.8 indicative of low intra-granular porosity. 相似文献
996.
Abid Abdul Ghafoor Ashiq Muhammad Faheem Alfryyan Nada Manzoor Sumaira Nisa Mehar Un Al-Buriahi M. S. Alomairy Sultan Alrowaili Z. A. Ashiq Muhammad Naeem 《Journal of Solid State Electrochemistry》2022,26(10):2107-2118
Journal of Solid State Electrochemistry - The discovery of highly active and cost-effective materials capable of catalyzing the oxygen evolution reaction (OER) is essential for water splitting. In... 相似文献
997.
Muhammad Bachal Korai Ghulam Abbas Shar Gul Afshan Soomro Muhammad Aslam Korai Maqsood Ahmed Mirbahar Abdul Samad Nisar Abbas Shar 《印度化学会志》2022,99(4):100360
A simple and rapid spectrophotometric technique has been designed for the trace copper analysis employing 1-(2-Thiazolylazo)-2-naphthol (TAN) reagent in aqueous micellar solution of cetyl trimethylammonium bromide (CTAB) as a surfactant. Copper complexed with 1-(2-Thiazolylazo)-2-naphthol to form bis[1-(2-Thiazolylazo)-2-naphthol]copper. The present spectrophotometric technique was very important since the micellar system was used in place of the toxic, high cost and time-consuming solvent extraction steps. The technique showed an enhanced detection efficiency, specificity, and molar absorptivity. It was found that the molar absorption coefficient and sensitivity of Sandel were ε 2.45 × 104 L mol?1cm?1 and 2.6 ngcm?2 at λmax 578.4 nm. A linear calibration plot in the range 0.12–5.0 μg mL?1 was obtained; a stoichiometric metal ligand ratio [M:L] of 1:2 was found for the formation of Cu-[TAN]2. The complex was formed at pH 9.5 and was stable up to 24 h. The proposed technique has been employed to study copper from different alloys, biological, environmental and pharmaceutical samples. 相似文献
998.
Sjahro Noerhidajat Yunus Robiah Abdullah Luqman Chuah Rashid Suraya Abdul Asis Ahmad Jaril Akhlisah Z. N. 《Cellulose (London, England)》2021,28(12):7521-7557
Cellulose - Inappropriate discharge of industrial wastewater and household effluent has led to an accumulation of hazardous organic substances, oil and grease, heavy metal ions, dyes, and leftover... 相似文献
999.
Traditional risk measurements have proven inadequate in capturing tail risk and nonlinear correlation. This study proposes a novel approach to measure financial risk in the Internet finance industry: a new Value-at-Risk (VaR) measurement based on quantile regression neural network (QRNN). Sparrow Search Algorithm (SSA) is utilized to optimize the QRNN model, which improves the model's performance in predicting internet finance risk. By comparing the TGARCH-VaR and QR-VaR approaches, our study demonstrates the effectiveness of the QRNN-VaR approach and its potential to improve the accuracy of risk prediction in the Internet finance industry. This study further examines and compares the risks between the traditional and internet finance industries. It also considers the unique impact of COVID-19 on industry risk based on statistical testing for differences and machine learning models. Our results indicate that the level of risk in the Internet finance industry is higher than in the traditional finance industry. Moreover, COVID-19 has contributed to increased risk within the Internet finance industry. These findings have significant implications for investors and policymakers seeking to better understand and manage risks within the Internet finance industry, particularly in the ongoing COVID-19 pandemic. 相似文献
1000.
Nadeem Muhammad Muhammad Zia-ul-Haq Amjad Ali Sumaira Naeem Azeem Intisar Dongxue Han Hairong Cui Yan Zhu Jia-Lun Zhong Abdul Rahman Binnian Wei 《Arabian Journal of Chemistry》2021,14(3):102972
Ion chromatography (IC) is a well-known technique for trace determination of inorganic ions and small organic acids. Recently, it has also appeared as a promising alternative to reverse phase chromatography for the determination of polar pesticides and pharmaceutical drugs in various sample matrices. Therefore, this study aims to provide a comprehensive overview of the application of IC coupled to fluorescence (FLD) or UV detector for the determination of pesticides and pharmaceutical drugs in samples from all walks of life. Apart from advantages and limitations, a short comparison of IC-FLD/UV with other techniques especially reverse-phase chromatography was drawn to envision future research efforts in this direction. Finally, several related areas such as IC hyphenation with different detectors (spectroscopic and spectrometer), miniaturization, automation, green chemistry, mobile phase, column, sample preparation, etc., were discussed to highlight its application for the determination of a wide range of analytes in the complex sample matrix. 相似文献