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排序方式: 共有357条查询结果,搜索用时 15 毫秒
91.
Md. Ruhul Amin Farhana Yasmin Mohammed Anowar Hosen Sujan Dey Shafi Mahmud Md. Abu Saleh Talha Bin Emran Imtiaj Hasan Yuki Fujii Masao Yamada Yasuhiro Ozeki Sarkar Mohammad Abe Kawsar 《Molecules (Basel, Switzerland)》2021,26(22)
A series of methyl β-D-galactopyranoside (MGP, 1) analogs were selectively acylated with cinnamoyl chloride in anhydrous N,N-dimethylformamide/triethylamine to yield 6-O-substitution products, which was subsequently converted into 2,3,4-tri-O-acyl analogs with different acyl halides. Analysis of the physicochemical, elemental, and spectroscopic data of these analogs revealed their chemical structures. In vitro antimicrobial testing against five bacteria and two fungi and the prediction of activity spectra for substances (PASS) showed promising antifungal functionality comparing to their antibacterial activities. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) tests were conducted for four compounds (4, 5, 6, and 9) based on their activity. MTT assay showed low antiproliferative activity of compound 9 against Ehrlich’s ascites carcinoma (EAC) cells with an IC50 value of 2961.06 µg/mL. Density functional theory (DFT) was used to calculate the thermodynamic and physicochemical properties whereas molecular docking identified potential inhibitors of the SARS-CoV-2 main protease (6Y84). A 150-ns molecular dynamics simulation study revealed the stable conformation and binding patterns in a stimulating environment. In-silico ADMET study suggested all the designed molecules to be non-carcinogenic, with low aquatic and non-aquatic toxicity. In summary, all these antimicrobial, anticancer and in silico studies revealed that newly synthesized MGP analogs possess promising antiviral activity, to serve as a therapeutic target for COVID-19. 相似文献
92.
Yasmin A. Ranasinghe Gary L. Glish 《Journal of the American Society for Mass Spectrometry》1996,7(5):473-481
The reactions of phenylium with water and ammonia and their methyl homologs have been investigated using a quadrupole ion trap and semiempirical molecular orbital calculations. The results indicate that both types of molecules react with phenylium through lone pair electrons even though, for methyl-containing compounds, insertion into a C-H bond would lead to more stable products. For the excited adducts formed by reaction with methyl-containing reactant neutrals, the only dissociation observed is loss of a methyl radical. Neutral losses of H2 or CH4, which are more thermodynamically stable, are not observed, which indicates that these reactions are either not kinetically competitive or have high energy transition states due to the fact that the reactions would need to occur via orbital symmetry forbidden 1,2 eliminations. 相似文献
93.
Farrah Syazana Khattulanuar Mahendran Sekar Shivkanya Fuloria Siew Hua Gan Nur Najihah Izzati Mat Rani Subban Ravi Kumarappan Chidambaram M. Yasmin Begum Abul Kalam Azad Srikanth Jeyabalan Arulmozhi Dhiravidamani Lakshmi Thangavelu Pei Teng Lum Vetriselvan Subramaniyan Yuan Seng Wu Kathiresan V. Sathasivam Neeraj Kumar Fuloria 《Molecules (Basel, Switzerland)》2022,27(3)
Cardiovascular disorders (CVDs) are the leading risk factor for death worldwide, and research into the processes and treatment regimens has received a lot of attention. Tilianin is a flavonoid glycoside that can be found in a wide range of medicinal plants and is most commonly obtained from Dracocephalum moldavica. Due to its extensive range of biological actions, it has become a well-known molecule in recent years. In particular, numerous studies have shown that tilianin has cardioprotective properties against CVDs. Hence, this review summarises tilianin’s preclinical research in CVDs, as well as its mechanism of action and opportunities in future drug development. The physicochemical and drug-likeness properties, as well as the toxicity profile, were also highlighted. Tilianin can be a natural lead molecule in the therapy of CVDs such as coronary heart disease, angina pectoris, hypertension, and myocardial ischemia, according to scientific evidence. Free radical scavenging, inflammation control, mitochondrial function regulation, and related signalling pathways are all thought to play a role in tilianin’s cardioprotective actions. Finally, we discuss tilianin-derived compounds, as well as the limitations and opportunities of using tilianin as a lead molecule in drug development for CVDs. Overall, the scientific evidence presented in this review supports that tilianin and its derivatives could be used as a lead molecule in CVD drug development initiatives. 相似文献
94.
Andrii Mahun Sabina Abbrent Jiri Czernek Jan Rohlicek Hana Mackov Weihua Ning Rafa Konefa Jií Brus Libor Kobera 《Molecules (Basel, Switzerland)》2021,26(19)
Spikelets NMR spectra are very popular as they enable the shortening of experimental time and give the possibility to obtain required NMR parameters for nuclei with ultrawide NMR patterns. Unfortunately, these resulted ssNMR spectra cannot be fitted directly in common software. For this reason, we developed UWNMRSpectralShape (USS) software which transforms spikelets NMR patterns into single continuous lines. Subsequently, these reconstructed spectral envelopes of the (Q)CPMG spikelets patterns can be loaded into common NMR software and automatically fitted, independently of experimental settings. This allows the quadrupole and chemical shift parameters to be accurately determined. Moreover, it makes fitting of spikelets NMR spectra exact, fast and straightforward. 相似文献
95.
Shehla Sattar Samina Siddiqui Asim Shahzad Asghari Bano Muhammad Naeem Rahib Hussain Naeem Khan Basit Latief Jan Humaira Yasmin 《Molecules (Basel, Switzerland)》2022,27(6)
Nano-bioremediation application is an ecologically and environmentally friendly technique to overcome the catastrophic situation in soil because of petroleum waste contamination. We evaluated the efficiency of oil-degrading bacterial consortium and silver nanoparticles (AgNPs) with or without fertilizer to remediate soils collected from petroleum waste contaminated oil fields. Physicochemical characteristics of control soil and petroleum contaminated soils were assessed. Four oil-degrading strains, namely Bacillus pumilus (), Exiguobacteriaum aurantiacum ( KY010576), Lysinibacillus fusiformis ( KY010578), and Pseudomonas putida ( KY010586), were selected based on their in vitrohydrocarbon-degrading efficiency. In a lab experiment, contaminated soils were treated alone and with combined amendments of the bacterial consortium, AgNPs, and fertilizers (ammonium nitrate and diammonium phosphate). We detected the degradation rate of total petroleum hydrocarbons (TPHs) of the soil samples with GC-FID at different intervals of the incubation period (0, 5, 20, 60, 240 days). The bacterial population (CFU/g) was also monitored during the entire period of incubation. The results showed that 70% more TPH was degraded with a consortium with their sole application in 20 days of incubation. There was a positive correlation between TPH degradation and the 100-fold increase in bacterial population in contaminated soils. This study revealed that bacterial consortiums alone showed the maximum increase in the degradation of TPHs at 20 days. The application of nanoparticles and fertilizer has non-significant effects on the consortium degradation potential. Moreover, fertilizer alone or in combination with AgNPs and consortium slows the rate of degradation of TPHs over a short period. Still, it subsequently accelerates the rate of degradation of TPHs, and a negligible amount remains at the end of the incubation period. KX580766相似文献
96.
Saverio Russo Alberto Mariani Sabina L. E. Mazzanti Giacomo Ruggeri Giuseppina Conio 《Macromolecular Symposia》1997,122(1):1-6
The direct syntheses of poly(p-phenyleneterephthalamide) in presence of poly(vinylpyrrolidone) and poly(4-vinylpyridine) as matrices have been carried out following the so-called Yamazaki's and Higashi's methods. The intrinsic viscosity data of the resulting polyamide were found to be strongly dependent on the matrix used as well as on its molecular weight. 相似文献
97.
A new sono-electrochemical method for enhanced detoxification of hydrophilic chloroorganic pollutants in water 总被引:8,自引:0,他引:8
Yasman Y Bulatov V Gridin VV Agur S Galil N Armon R Schechter I 《Ultrasonics sonochemistry》2004,11(6):649-372
A new method for detoxification of hydrophilic chloroorganic pollutants in effluent water was developed, using a combination of ultrasound waves, electrochemistry and Fenton's reagent. The advantages of the method are exemplified using two target compounds: the common herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and its derivative 2,4-dichlorophenol (2,4-DCP). The high degradation power of this process is due to the large production of oxidizing hydroxyl radicals and high mass transfer due to sonication. Application of this sono-electrochemical Fenton process (SEF) treatment (at 20 kHz) with quite a small current density, accomplished almost 50% oxidation of 2,4-D solution (300 ppm, 1.2 mM) in just 60 s. Similar treatments ran for 600 s resulted in practically full degradation of the herbicide; sizable oxidation of 2,4-DCP also occurs. The main intermediate compounds produced in the SEF process were identified. Their kinetic profile was measured and a chemical reaction scheme was suggested. The efficiency of the SEF process is tentatively much higher than the reference degradation methods and the time required for full degradation is considerably shorter. The SEF process maintains high performance up to concentrations which are higher than reference methods. The optimum concentration of Fe2+ ions required for this process was found to be of about 2 mM, which is lower than that in reference techniques. These findings indicate that SEF process may be an effective method for detoxification of environmental water. 相似文献
98.
Reactions of the new acyclic ligand DNBH with RuCl3 · 3H2O, followed by addition of a secondary ligand L (L = PPh3, 1,10-phenanthroline, 2,2-bipyridine, pyridine and 2,4-diaminotoluene), yield six binuclear metal complexes, TR1–TR6. Two different methods were employed: template and a two-step synthesis, both yielding the same complexes. DNBH and its metal complexes were characterised by a combination of spectroscopic, elemental and magnetic susceptibility data. Coordination was found to be through the carbonyl oxygen of amide and phenolic oxygen in the octahedral environment of the metal. DNBH and some of the metal complexes display antibacterial properties. 相似文献
99.
Naji Al Dahoudi Amal AlKahlout Sabina Heusing Petra Herbeck-Engel Rudolf Karos Peter Oliveira 《Journal of Sol-Gel Science and Technology》2013,67(3):556-564
Crystalline indium doped zinc oxide (IZO) nanopowders were synthesized using hydrothermal treatment processing. Increasing the doping ratio of indium in the zinc oxide significantly influences the phase structure and shape of the nanopowders resulting in nanorod to nanoparticulate morphologies. As the doping profile increases, the crystallite size decreases, the band gap energy blue shifts and the specific surface area increases (measured by BET method). Additionally Raman spectroscopy exhibited shifts of several peaks, as well as revealed new peaks, confirming the substitution of indium ions within the zinc oxide lattice sites. An IZO suspension made of IZO nanoparticles (In/Zn = 3 atm.%) with a zeta potential greater than 30 mV at pH = 6 was successfully spin-coated on glass substrates for to make transparent conductive coatings evincing sheet resistances as low as 35 kΩ□ (ρ = 4.9 × 10?3 Ω m,) with transmission in the visible range as high as 90 %. 相似文献
100.
Valentina Pedoia Sabina Strocchi Vittoria Colli Elisabetta Binaghi Leopoldo Conte 《Magnetic resonance imaging》2013
In this study new evaluation strategies for comparing different Statistical Parametric Maps computed from fMRI time-series analysis software tools are proposed. The aim of our work is to assess and quantitatively evaluate the statistical agreement of activation maps. Some pre-processing steps are necessary to compare SPMs (Statistical Parametric Maps), including segmentation and co-registration. The study of the statistical agreement is carried out following two ways. The first way considers SPMs as the result of two classification processes and extracts confusion matrix and Cohen's kappa index to assess agreement. Some considerations will be made on the statistical dependence of classes and a new formulation of kappa index will be used for overcoming this problem. The second way considers SPMs as two 3D images, and computes the similarity of SPMs images with a fuzzy formulation of the Jaccard Index. Several experiments were conducted both to assess the performance of the proposed evaluation tools and to compare activation maps computation pipelines from two widely used software tools in a clinical context. 相似文献