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61.
62.
T.P. Shakhtshneider S.A. Kuznetsova A.S. Zamay T.N. Zamay E.A. Spivak M.A. Mikhailenko 《Natural product research》2016,30(12):1382-1387
Betulin and its esters are the natural compounds with high in vitro cytotoxicity toward many cancer cells. However, the poor water solubility of these compounds has limited their applications. We prepared new composites of betulin esters using two methods, namely ball-milling of the mixtures of betulin esters with arabinogalactan and preparation of thin films of these mixtures by evaporating the aqueous solutions. These composites revealed higher water solubility as compared with the initial substances without losing the structural integrity and functionality. As a result, the new composites have shown much higher inhibitory effects against different cancer cell lines such as Ehrlich ascites carcinoma cells and lung carcinoma cells (A549) in comparison with the initial substances. The cell viability studies based on Annexin V and Propidium iodide probes have confirmed the high proapoptotic effect of betulin ester derivatives against cancer cells. 相似文献
63.
An ionic liquid material containing small size cation was synthesized and its composition and structure was determined by FT-IR, 1H NMR, 13C NMR and element analysis. However, its physical properties such as melting point, viscosity, conductivity, etc. were measured and the results show that the novel ionic liquid is composed of small cation with highly symmetry and larger anion which is very rare among the reported ionic liquid family. 相似文献
64.
Ethylidene diacetate was prepared by reacting dimethyl ether, acetic acid and syngas in the presence of a catalytic system comprising RhI3, PPh3 and CH3I. The effects of reaction temperature, pressure, time and the CO/H2 molar ratio on the conversion of dimethyl ether and the product selectivity were investigated under the same catalyst formulation. Results showed that a maximum conversion of dimethyl ether was obtained when a mixture consisting of 0.3 mol dimethyl ether and 120 ml acetic acid was reacted at 180 ℃ and 3.0 MPa for 10 h at a stirring speed of 600 rpm under a syngas flow with a CO/H2 molar ratio of 2.5, which was catalyzed by a catalyst mixture comprising 0.3 g RhI3, 6 g PPh3 and 1.3 g CH3I. The selectivity of ethylidene diacetate increased with temperature, decreased with the CO/H2 molar ratio and exhibited a maximum with pressure. 相似文献
65.
A mild and efficient synthetic protocol for the oxidation of benzil-α-arylimino oximes 3 utilizing iodobenzene diacetate (IBD) as an oxidizing agent has been developed. Oximes 3, obtained by the condensation of (E)-benzil monoxime 2 with various appropriately substituted anilines 1, on treatment with iodobenzene diacetate in dichloromethane at room temperature underwent oxidative cyclization to afford 2,3-diphenylquinoxaline-1-oxide 4 in excellent yields. 相似文献
66.
A direct and efficient method for the preparation of 5‐benzoyldihydro‐2(3H)‐furanones was realized by cyclization of 4‐benzoylbutyric acids in the presence of phenyliodine(III) triflate. 相似文献
67.
A simple, efficient, and green procedure for Knoevenagel condensation of aromatic aldehydes with malononitrile and ethyl cyanoacetate catalyzed by ethylenediammonium diacetate under solvent-free conditions at room temperature is reported. This method gives remarkable advantages such as a simple procedure, mild conditions, fast (1–45 min) reactions, and excellent yields. Additionally, the catalyst can be reused for at least five runs without significant decrease of the yields. 相似文献
68.
A series of 2-hydroxyaryl ketoximes were converted to the corresponding 1,2-benzisoxazole 2-oxides by treatment with iodobenzene diacetate (in acetic acid or methanol) or N-chlorosuccinimide in water. Both methods gave moderate to excellent yields for a variety of substituted oximes under mild conditions within short reaction times. The latter method has the advantages of an aqueous solvent and lack of halogenated organic by-products. 相似文献
69.
4-Substituted Hantzsch 1,4-dihydropyridines and 1,3,5-trisubstituted pyrazolines were oxidized to the corresponding pyridines and pyrazoles, respectively, in high yields by molecular oxygen in the presence of catalytic amount of N-hydroxyphthalimide (NHPI) and Co(OAc)2 in acetonitrile at room temperature. 相似文献
70.
Triphenylantimony dicarboxylates Ph3Sb(OAc)2 and Ph3Sb(O2CEt)2 are efficient C-phenylating agents for methyl acrylate. In the presence of the Pd(OAc)2, Li2PdCl4 or Pd2(dba)3(CHCl3) catalysts in MeCN at 50 °C, methyl cinnamate forms in 70—150% yield with respect to SbV. Copper(ii) salts do not increase the reaction yield. 相似文献