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51.
A new class of 3,4‐disubstituted pyrroles has been prepared by the reaction of 1‐aroyl‐2‐arylsul‐fonylethenes and 1,2‐diarylsulfonylethenes with tosyl methyl isocyanide.  相似文献   
52.
The high cost of the bridging liquid subdues the implementation and commercialization of oil agglomeration process. To overcome this problem, waste oils from different sectors were used in this present study. The performance of the process was assessed based on the responses like ash rejection and organic matter recovery. The aim of the present study was to investigate the usage of waste oils from different sectors and to optimize and analyze the behavioral pattern showcased by different variables (pulp density, oil dosage, agglomeration time and oil type) using response surface methodology (Box-Behnken design). Experimental investigation shows that the optimum pulp density, oil dosage, agglomeration time and oil type condition obtained as 3%, 15%, 15?min and waste engine oil, respectively. At optimum condition, the % ash rejection and % organic matter recovery obtained as 63.94% and 81.8%, respectively.  相似文献   
53.
The gelating abilities of ricinelaidic acid (d ‐REA), the trans‐isomer of ricinoleic acid (d ‐RA), and a series of its alkylammonium and alkane‐α,ω‐diammonium salts have been examined in a wide range of organic liquids. The gelation efficiency of the trans acid is much better than that of the cis, although neither is as efficient as is the completely saturated molecular gelator analogue, (R)‐12‐hydroxystearic acid (d ‐12HSA). The formation of ammonium salts also improves the gelation ability of d ‐REA in high polarity liquids. The gelating properties are highly dependent upon the chain length of the alkyl group of the alkylammonium salts, but not very dependent on the chain length of the alkane‐α,ω‐diammonium salts. Structural insights from Fourier transform infrared spectroscopy and powder X‐ray diffraction indicate that the absence or presence of unsaturation, the incorporation of (charged) ammonium centers, and the different chain lengths of the alkylammonium salts lead to different packing arrangements and different strengths of H‐bonding interactions within the gel assemblies of the d ‐REA derivatives. Insights into the relationships among the various systematic structural changes to d ‐REA and the properties of their aggregated structures, including the gel states, are provided.  相似文献   
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The aim of the present study was to evaluate the contribution of metabolites to drug–drug interaction and drug–herb interaction using the inhibition of CYP2D6 and CYP3A4 by metoprolol (MET) and its metabolites. The peak concentrations of unbound plasma concentration of MET, α‐hydroxy metoprolol (HM), O‐desmethyl metoprolol (ODM) and N‐desisopropyl metoprolol (DIM) were 90.37 ± 2.69, 33.32 ± 1.92, 16.93 ± 1.70 and 7.96 ± 0.94 ng/mL, respectively. The metabolites identified, HM and ODM, had a ratio of metabolic area under the concentration–time curve (AUC) to parent AUC of ≥0.25 when either total or unbound concentration of metabolite was considered. In vitro CYP2D6 and CYP3A4 inhibition by MET, HM and ODM study revealed that MET, HM and ODM were not inhibitors of CYP3A4‐catalyzed midazolam metabolism and CYP2D6‐catalyzed dextromethorphan metabolism. However, DIM only met the criteria of >10% of the total drug related material and <25% of the parent using unbound concentrations. If CYP inhibition testing is solely based on metabolite exposure, DIM metabolite would probably not be considered. However, the present study has demonstrated that DIM contributes significantly to in vitro drug–drug interaction. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
58.
The kinetics of thermal polymerization of methyl methacrylate initiated by the redox system Mn(III)–glycerol was studied in aqueous sulfuric acid in the temperature range of 30–40°C, and the rates of polymerization, Rp, and Mn3+ disappearance, etc., were measured. The effect of certain water-miscible organic solvents and certain cationic and anionic surfactants on the rates of polymerization has been investigated. A mechanism involving the formation of a complex between Mn3+ and glycerol whose decomposition yields the initiating free radical with the polymerization being terminated by the metal ion has been suggested.  相似文献   
59.
Novel bisheterocycles, 1,2,3‐selenadiazoles, thiadiazoles and 2H‐diazaphospholes in combination with oxadiazoles, thiadiazoles and triazoles were prepared from phenacylsulfonylacetic acid methyl ester.  相似文献   
60.
A variety of amide derivatives of (6-chloro-2,3-dihydro-1H-inden-1-yl)acetic acid were synthesized and screened for their anti-inflammatory and related biological activities. These compounds were found to be longer acting and showed residual activity exceeding that of standard indomethacin. The studies with SKF-525A, a standard hepatic microsomal enzyme inhibitor showed that probably the test compound per se is the active species. The compound 6y showed best activity profile with ED30 of 6.45 mg/kg however this compound was found to be toxic at 100 mg/kg p.o. Though these compounds exhibited appreciable analgesic and antipyretic activities but they failed to prevent the development of secondary inflammation in adjuvant induced arthritis assay. The compound 6x showed 94% inhibition of acetic acid induced writhing. Studies showed that antagonism of TNF-alpha is not possibly involved in the mechanism of action of these compounds. However these compounds were found to have only mild ulcerogenic potential at the tested dose level of 100 mg/kg p.o. in comparison to indomethacin.  相似文献   
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