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21.
Yasir Nazir Hummera Rafique Naghmana Kausar Qamar Abbas Zaman Ashraf Pornchai Rachtanapun Kittisak Jantanasakulwong Warintorn Ruksiriwanich 《Molecules (Basel, Switzerland)》2021,26(9)
Targeting tyrosinase for melanogenesis disorders is an established strategy. Hydroxyl-substituted benzoic and cinnamic acid scaffolds were incorporated into new chemotypes that displayed in vitro inhibitory effects against mushroom and human tyrosinase for the purpose of identifying anti-melanogenic ingredients. The most active compound 2-((4-methoxyphenethyl)amino)-2-oxoethyl (E)-3-(2,4-dihydroxyphenyl) acrylate (Ph9), inhibited mushroom tyrosinase with an IC50 of 0.059 nM, while 2-((4-methoxyphenethyl)amino)-2-oxoethyl cinnamate (Ph6) had an IC50 of 2.1 nM compared to the positive control, kojic acid IC50 16700 nM. Results of human tyrosinase inhibitory activity in A375 human melanoma cells showed that compound (Ph9) and Ph6 exhibited 94.6% and 92.2% inhibitory activity respectively while the positive control kojic acid showed 72.9% inhibition. Enzyme kinetics reflected a mixed type of inhibition for inhibitor Ph9 (Ki 0.093 nM) and non-competitive inhibition for Ph6 (Ki 2.3 nM) revealed from Lineweaver–Burk plots. In silico docking studies with mushroom tyrosinase (PDB ID:2Y9X) predicted possible binding modes in the catalytic site for these active compounds. Ph9 displayed no PAINS (pan-assay interference compounds) alerts. Our results showed that compound Ph9 is a potential candidate for further development of tyrosinase inhibitors. 相似文献
22.
23.
Peilin Deng Fan Yang Zhitong Wang Shenghua Chen Yinzheng Zhou Shahid Zaman Prof. Dr. Bao Yu Xia 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(27):10899-10905
Carbon dioxide (CO2) conversion is promising in alleviating the excessive CO2 level and simultaneously producing valuables. This work reports the preparation of carbon nanorods encapsulated bismuth oxides for the efficient CO2 electroconversion toward formate production. This resultant catalyst exhibits a small onset potential of −0.28 V vs. RHE and partial current density of over 200 mA cm−2 with a stable and high Faradaic efficiency of 93 % for formate generation in a flow cell configuration. Electrochemical results demonstrate the synergistic effect in the Bi2O3@C promotes the rapid and selective CO2 reduction in which the Bi2O3 is beneficial for improving the reaction kinetics and formate selectivity, while the carbon matrix would be helpful for enhancing the activity and current density of formate production. This work provides effective bismuth-based MOF derivatives for efficient formate production and offers insights in promoting practical CO2 conversion technology. 相似文献
24.
Al-Ameen Bariz OmarAli Ahmed Jasim M. Al-Karawi Adil A. Awad Necmi Dege Sevgi Kansz Erbil Agar Zaman Ahmed Hussein Iman Rajab Mohammed 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(5):476-482
Reaction of N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide), C20H18F2N4O2, ( LF ), with zinc chloride and mercury(II) chloride produced different types and shapes of neutral coordination complexes, namely, dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ2N,O]zinc(II), [ZnCl2(C20H18F2N4O2)], ( 1 ), and dichlorido[N,N′‐(cyclohexane‐1,2‐diylidene)bis(4‐fluorobenzohydrazide)‐κ4O,N,N′,O′]mercury(II), [HgCl2(C20H18F2N4O2)], ( 2 ). The organic ligand and its metal complexes are characterized using various techniques: IR, UV–Vis and nuclear magnetic resonance (NMR) spectroscopies, in addition to powder X‐ray diffraction (PXRD), single‐crystal X‐ray crystallography and microelemental analysis. Depending upon the data from these analyses and measurements, a typical tetrahedral geometry was confirmed for zinc complex ( 1 ), in which the ZnII atom is located outside the bis(benzhydrazone) core. The HgII atom in ( 2 ) is found within the core and has a common octahedral structure. The in vitro antibacterial activities of the prepared compounds were evaluated against two different bacterial strains, i.e. gram positive Bacillus subtilis and gram negative Pseudomonas aeruginosa bacteria. The prepared compounds exhibited differentiated growth‐inhibitory activities against these two bacterial strains based on the difference in their lipophilic nature and structural features. 相似文献
25.
Syed Tawab Shah Zaira Zaman Chowdhury Mohd. Rafie Bin Johan Irfan Anjum Badruddin H. M. T. Khaleed Sarfaraz Kamangar Hussein Alrobei 《Molecules (Basel, Switzerland)》2022,27(3)
Functionalized magnetite nanoparticles (Fe3O4) were prepared using the coprecipitation method followed by functionalization with a multipotent antioxidant (MPAO). The MPAO was synthesized and analyzed using FTIR and NMR techniques. In this study, the functionalized nanoparticles (IONP@AO) were produced and evaluated using the FTIR, XRD, Raman, HRTEM, FESEM, VSM, and EDX techniques. The average determined particle size of IONP@AO was 10 nanometers. In addition, it demonstrated superparamagnetic properties. The magnitude of saturation magnetization value attained was 45 emu g−1. Virtual screenings of the MPAO’s potential bioactivities and safety profile were performed using PASS analysis and ADMET studies before the synthesis step. For the DPPH test, IONP@AO was found to have a four-fold greater ability to scavenge free radicals than unfunctional IONP. The antimicrobial properties of IONP@AO were also demonstrated against a variety of bacteria and fungi. The interaction of developed nanoantioxiants with biomolecules makes it a broad-spectrum candidate in biomedicine and nanomedicine. 相似文献
26.
In this paper, recent advances in the study of rheological behavior of concentrated bimodal suspensions are briefly reviewed. The predictive models are divided into two categories, namely, the effective volume fraction (or hard sphere scaling) approach and the separation of contributions approach. Predictions of both approaches are compared with experimental data of electrostatically and sterically stabilized suspensions. It is shown that the predictions of both hard sphere scaling and the scaling method of Zaman and Moudgil (J. Colloid Interface Sci. 212 (1999) 167) to separate the contributions of fine and coarse particles are in good agreement with the experimentally observed results. The approach by Dames, Morrison, Wilenbacher (Rheol. Acta 40 (2001) 434) to separate the hard-sphere and non-hard-sphere contributions is investigated using the aqueous silica and polystyrene suspensions respectively. A good agreement is shown for aqueous silica suspensions. However, significant differences between the predictions and experimental data are found for the sterically stabilized polystyrene suspensions, suggesting a more generalized expression is needed. As an attempt to classify the models on the viscosity of colloidal suspensions, the present study will provide guidelines for interpretation of experimental results and for the development of more comprehensive predictive methodologies for polydispersed colloidal dispersions. 相似文献
27.
Development and application of sub‐2‐μm particle CO2‐based chromatography coupled to mass spectrometry for comprehensive analysis of lipids in cottonseed extracts 下载免费PDF全文
28.
K.R. Allakhverdiev M.A. Nizametdinova E.Yu. Salaev R.M. Sardarly N.Yu. Safarov E.A. Vinogradov G.N. Zhizhin 《Solid State Communications》1980,36(6):527-532
The lattice vibration spectra of TlS and TllnSe2 crystals were investigated by infrared reflectivity in the wavenumber range from 20 to 5000 cm?1. The frequencies of K = 0 phonons were determined by Kramers-Kronig analysis of the spectra. All five infrared active lattice vibrations predicted by the group theoretical analysis were identified. The normal coordinates of vibrations for five infrared active phonons were determined. In the approximation which does not take into consideration long range Coulomb interaction values of the force constant and effective changes are obtained for TlSe, TlS and TllnSe2 crystals. 相似文献
29.
I. M. Biktagirov L. Kh. Faizullina Sh. M. Salikhov M. G. Safarov F. A. Valeev 《Russian Journal of Organic Chemistry》2014,50(9):1317-1322
4,4-Dimethyl-3-nitro-10,11-dioxatricyclo[6.2.1.02,6]undec-5-en-7-one possessing a bicyclic iridoid skeleton was synthesized in two steps from isolevoglucosenone which was obtained in turn from levoglucosenone through 4-benzyloxy-2-tosyloxy derivative. 相似文献
30.
M. A. Kukaniev M. M. Akbarova Z. G. Sangov S. S. Safarov D. M. Osimov 《Chemistry of Heterocyclic Compounds》2010,46(5):605-607
A one-reactor method has been developed for the synthesis of 3-methyl-6-R-6H-thiazolo[4,3-b]-1,2,4-triazolo[4,3-d]-1,3,4-thiadiazoles
by the condensation of aromatic aldehydes, thioglycolic acid, and 4-amino-5-methyl-1,2,4-triazole-3(2H)-thione in a sulfuric
acid medium. 相似文献