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971.
A series of new dispiropyrrolidine derivatives were synthesized via the three‐component 1,3‐dipolar cycloaddition reaction of azomethine ylides generated in situ by the decarboxylative condensation of acenaphthenequinone and sarcosine or l ‐thioproline with 5‐benzylidene‐1,3‐dimethylpyrimidine‐2,4,6‐trione. The structures of the products were identified by IR, 1H‐NMR, and HRMS spectra. 相似文献
972.
Radia Bouasla Hadjira Berredjem Malika Berredjem Malika Ibrahim‐Oualid Assia Allaoui Marc Lecouvey Nour‐Eddine Aouf 《Journal of heterocyclic chemistry》2013,50(6):1328-1332
A new series of chiral 5‐substituted bis‐oxazolidinones containing an acylsulfonamide moiety has been synthesized starting from chlorosulfonyl isocyanate, (l )‐ethyl lactate, and oxazolidin‐2‐ones. All the reactions were conducted at ambient temperature, and the N‐acylsulfonamide bis‐oxazolidin‐2‐ones were obtained with high yields within 2 h. Some of the newly synthesized compounds were evaluated in vitro against the virulent strain RH of Toxoplasma gondii and the human lymphocytes, and showed promising results. 相似文献
973.
Zhongke Yan Jianwei Zhao Lirong Qin Fan Mu Ping Wang Xining Feng 《Mikrochimica acta》2013,180(1-2):145-150
Granular nanowires with a diameter of about 60 nm were fabricated from cuprous oxide (Cu2O) by an electrochemical method using anodic aluminium oxide as the template. A non-enzymatic sensor for hydrogen peroxide (H2O2) was then developed on the basis of a gold electrode modified with Cu2O nanowires and Nafion. The resulting sensor enables the determination of H2O2 with a sensitivity of 745 μA?mM?1?cm?2, over a wide linear range (0.25 μM to 5.0 mM), and with a low detection limit (0.12 μM). The results demonstrate that the use of such granular nanowires provides a promising tool for the design of non-enzymatic chemical sensors. Figure
A non-enzymatic sensor for hydrogen peroxide (H2O2) was developed on the basis of a gold electrode modified with Cu2O nanowires and Nafion. The resulting sensor enables the determination of H2O2 with a sensitivity of 745 μA mM?1 cm?2, over a wide linear range (0.25 μM to 5.0 mM), and with a low detection limit (0.12 μM). The results demonstrate that the use of such granular nanowires provides a promising tool for the design of non-enzymatic chemical sensors 相似文献
974.
An improved One-step Beckmann rearrangement is described. 相似文献
975.
The chloromethylation of aromatic hydrocarbons proceeded efficiently using the reusable ionic liquid [emim]BF4 as promoter. The reactions were completed in 5 h at 70°C with good yields and easy workup. 相似文献
976.
A selective and effective oxidation of alcohols into the corresponding aldehydes and ketones, respectively, with a new reagent, ferric(III) nitrate supported on kieselguhr, under heterogeneous conditions is reported. 相似文献
977.
Mirosław Giurg Katarzyna Piekielska Magdalena Gębala Bartosz Ditkowski Marcin Wolański Wanda Peczyńska‐Czoch 《合成通讯》2013,43(11):1779-1789
The catalytic oxidative cyclocondensation of the o‐aminophenols 1a–f was investigated. The oxidants used were air/laccase, H2O2/horseradish peroxidase, H2O2/ebselen (3), and TBHP/diphenyl diselenide 4. The products obtained were 2‐amino‐3H‐phenoxazin‐3‐one—questiomycin A, its derivative 2b, and cinnabarinic acid and actinocin (2c,d). Substrates with methyl groups at 4 and 5 positions of benzene ring were converted to different dihydrophenoxazinones 2g,h. Compounds having chlorine atoms at the same positions underwent oxidation to planar phenoxa-zinones 2e,f with elimination of one hydrochloride molecule. 相似文献
978.
Use of microwave irradiation in the synthesis of arylidenemalononitrile and benzopyran derivatives in water without catalyst is a clean method with high yield. 相似文献
979.
Aminosulfonic acid is an environmentally friendly catalyst. Grinding a mixture of aromatic aldehydes, barbituric acid, and H2NSO3H at room temperature (without any solvent) gave 5‐arylidene barbituric acid in high yields, providing a simple and efficient route to synthesis of these compounds. 相似文献
980.
Tarek A. Salama Saad S. Elmorsy Abdel‐Galel M. Khalil Margret M. Girges Abdel‐Aziz S. El‐Ahl 《合成通讯》2013,43(8):1313-1319
A combination of tetrachlorosilane and potassium cyanide (in situ trichlorosilyl cyanide) was found to work efficiently for hydrocyanation of ketones to afford the corresponding cyanohydrins in high yield under mild conditions. 相似文献