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181.
Purushottam Sidramappa Jamkhandi Srinivas Rajagopal 《Monatshefte für Chemie / Chemical Monthly》1968,99(4):1390-1394
Zusammenfassung Eine große Zahl von 3-acylierten 4-Hydroxy-1-thiacumarinen mit verschiedenen Halogen- oder Alkylsubstituenten am Benzolkern wurde durch Kondensation von 4-Hydroxy-1-thiacumarinen mit verschiedenen aliphatischen Säuren in Gegenwart von POCl3 synthetisiert.
Diese Veröffentlichung wird ein Teil der Dissertation vonP. S. Jamkhandi zur Erlangung des Ph.D. der Karnatak University sein. 相似文献
The synthesis of a large number of 3-acylated 4-hydroxy-1-thiacoumarins carrying various substituents in the benzenoid nucleus (halogen, alkyl) has been carried out by the condensation of 4-hydroxy-1-thiacoumarins with various aliphatic acids in the presence of phosphorus oxychloride.
Diese Veröffentlichung wird ein Teil der Dissertation vonP. S. Jamkhandi zur Erlangung des Ph.D. der Karnatak University sein. 相似文献
182.
Nand K. Singh Nagendra Singh Ajit Sodhi Anju Shrivastava Guru C. Prasad 《Transition Metal Chemistry》1996,21(6):556-559
Summary The new potential tetradentate ligand N-salicyl-N-thiobenzohydrazide (H2SBTH) and its Cu complex, [Cu(SBTH)], have been prepared and characterized by physico-chemical studies. In vivo antitumour activity of [Cu(SBTH)] has been tested against breast tumour in C3H/J strain mice; LD
50 values were also calculated. The cytotoxicity and antitumour effect of [Cu(SBTH)] is a maximum at 100 mg kg-1 body weight injected intraperitoneally in mice carrying breast tumour. In vitro results of the ligand and the complex on P-815 (murine mastocytoma) and K-562 (human erythroleukemia cells) indicate that these compounds show significant inhibition on 3H-thymidine and 3H-uridine incorporation in DNA and RNA in these tumour cells. Light microscopic study of the treated tumour mass demonstrated that certain cellular degradation, such as disappearance of mitotic figures, loss in cellular compactness, distortion of nucleus and disruption of cytoplasmic boundaries, take place in complex-treated mice with tumours. 相似文献
183.
Sushant Kumar Shrivastava Brijesh K. Patel Prabhash Nath Tripathi Pavan Srivastava Piyoosh Sharma Avanish Tripathi Ankit Seth Manish Kumar Tripathi 《Chemical Papers》2018,72(11):2769-2783
Some promising 4-thiazolone derivatives as lipoxygenase inhibitors were designed, synthesized, characterized and evaluated for anti-inflammatory activity and respective ulcerogenic liabilities. Compounds (1b, 1e, 3b, and 3e) exhibited considerable in vivo anti-inflammatory activity (57.61, 79.35, 75.00, and 79.35%) against carrageenan-induced rat paw edema model, whereas compounds (1e, 3b, and 3e) were found active against the arachidonic acid-induced paw edema model (55.38, 55.38, and 58.46%). The most potent compound (3e) exhibited lesser ulcerogenic liability compared to the standard diclofenac and zileuton. Further, the promising compounds (1e and 3e) were evaluated for in vitro lipoxygenase (LOX; IC50?=?12.98 µM and IC50?=?12.67 µM) and cyclooxygenase (COX) inhibition assay (COX-1; IC50?>?50 µM and, COX-2; IC50?>?50 µM). The enzyme kinetics of compound 3e was evaluated against LOX enzyme and supported by in silico molecular docking and molecular dynamics simulations studies. Overall, the results substantiated that 5-benzylidene-2-phenyl-4-thiazolones are promising pharmacophore for anti-inflammatory activity. 相似文献
184.
From a study of the polarograms of chlorides of lanthanum, praseodymium, neodymium, samarium, gadolinium, dysprosium and yttrium in 0.IN lithium chloride together with 0.01% gelatin as maximum suppressor, it has been shown that the reduction proceeds in two stages. M+3 + e ? M+2 and M+2 + 2e ? MIn the case of the less basic elements, anomalies in the heights of the second steps have been observed and these anomalies have been qualitatively explained on the basis of disturbing electrode reactions. The half-wave potentials for each step have been listed.Gelatin has not been found to be very efficient as a suppressor of maxima. In some cases a maximum is in evidence though partially. 相似文献
185.
O. N. Shrivastava J. K. Gupta C. M. Gupta 《Monatshefte für Chemie / Chemical Monthly》1973,104(1):57-63
Zusammenfassung An der Quecksilber-Tropfenelektrode zeigt In3+ bei Gegenwart von Glykolsäure, Brenztraubensäure, Buttersäure oder Lävulinsäure das für quasireversible Elektrodenprozesse typische Verhalten.
Mit 1 Abbildung 相似文献
Studies of the electrochemical behaviour of indium at the dropping-mercury electrode in the presence of some monocarboxylic acids
In the presence of glycolic, pyruvic, butyric or laevulinic acid In3+ at the dropping-mercury electrode behaves in a manner typical of quasi-reversible electrode processes.
Mit 1 Abbildung 相似文献
186.
AbstractInterlaminar fracture toughness had been the subject of great interest for several years and is still interesting to the research community. In this article, a comprehensive analysis of fracture toughness in FRP laminates is presented. Primarily, toughness studies are undertaken on glass and carbon fiber reinforced composites under mode-I and mode-II loading conditions. The fracture behavior and its failure pattern depend on a number of parameters: fiber sizing/coating, matrix modification, insert film, fiber volume fraction, stacking sequence, specimen geometry, loading rate and temperature change. In fact, a state-of-the-art process enables increasing fracture resistance with “matrix toughening by carbon nanotubes (CNT) inclusion”. It enables production of materials having ultra-high strength and low weight. The present study has highlighted the available techniques of CNT incorporation: mechanical mixing, grafting and interleaving. Other aspects, such as the dispersion level, matrix viscosity, fiber surface roughness, loading weight %, bonding strength with epoxy, height and density of grown CNT, energy absorption mechanism during delamination, etc., have been examined as well. Although a clear correlation of all these parameters with fracture toughness is hard to establish, there is growing understanding of the surface-grown CNTs and interleaving processes as they ensure significant increase in fracture toughness. 相似文献
187.
A series of novel calix[4]arene-based neutral semicarbazone and thiosemicarbazone receptors have been synthesized and characterized. The molecular receptor 4a recognizes in preference to other anions (Cl−, Br−, I−, , and ) through a 1:1 binding-stoichiometry. 相似文献
188.
Trials were conducted to evaluate the performance of three commonly used puddling implements, i.e. animal drawn rotary puddler (I1), 3-tine tiller (I2) and local plough (I3) under controlled soil bin conditions for different numbers of passes of each implement. The performance of the rotary puddler was found to be better when operated more than twice under the controlled conditions in terms of quality and quantity of puddling. It was found that the rotary puddler gave a higher puddling index and required less energy to puddle the soil. The rotary puddler provided good “puddle” with a puddling index of 50% after two passes whereas, the other two implements required more than five passes for the same quality of puddling or puddling index in sandy clay loam soil 相似文献
189.
Results of SEM and XRD studies, optical absorption spectra and photoluminescence emission spectra are presented for the films of (Cd0.95‐Pb0.05)S:CdCl2, Gd/Dy prepared by chemical bath deposition technique and using thiophenol and methanol as capping agents. The deposition of films is based on precipitation followed by condensation on the substrates. SEM studies show existence of irregular distribution of particles alongwith presence of rod/tube type structure. The XRD studies show diffraction lines of CdS, PbS and CdCl2. Blue shift has been observed in absorption spectra showing quantum confinement. Particle sizes determined from XRD studies and absorption spectral studies are found to lie in the nano range. Photoluminescence emission spectra consist of emissions in blue and green‐yellow regions. The observed emissions are related to the combination of defect levels and levels due to rare earths. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
190.
Navjot Sandhu Satish Kumar Pandey Ram Kumar Tittal Kamlesh Kumar Ashish Pratap Singh Rajesh K. Yadav Rahul Shrivastava Atul Pratap Singh 《Journal of heterocyclic chemistry》2021,58(12):2381-2389
The dimethyl sulfite as an alkylating as well as alkoxylating reagent is well known in synthetic organic as well as organometallic chemistry for a long time. Herein, we have utilized dimethyl sulfite as an alkylating reagent and reacted with fluorescein derivative, N-fluorescein-lactam-hydrazine ( B ). This reaction leads to the generation of tetramethylated fluorescein lactam hydrazine ( A ). The newly designed and synthesized molecule ( A ) has been characterized by 1H, 13C NMR and HRMS data. The antimicrobial activity of the synthesized alkylated fluorescein derivative has been tested against E. coli, P. aeruginosa, Salmonella typhimurium and S. aureus microbial agents. Time-kill assay results also confirmed that fluorescein derivative is a potent antimicrobial agent and revealed that the time-kill assay of fluorescein derivative is value-added than the well-known antibiotic. In addition, quantum chemical study was used to analyze its activity trend and correlated with the experimental data. The computed results of DFT revealed that the lipophilicity as well as the LUMO-HOMO band gap (ΔELUMO-HOMO = 4.75 eV) of compound A make it more suitable as an antimicrobial agent to match with in vitro antimicrobial experimental results. The MIC and MBC values of compound A were observed to be lower in contrast to fluorescein and ampicillin for all the tested bacterial strains, which were approximately 3- to 4-fold lower than MIC and MBC values of the later. Results obtained from the study clearly indicate that compound A has better antimicrobial and bactericidal activity in comparison to ampicillin and fluorescein. Synthesized compound can be a better substitute of traditionally used antibiotics, Ampicillin. 相似文献