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1.
报道了3-芳基-2-硫代-4-噻唑啉酮和3-芳基-5-苯甲酰基-2-硫代-4-噻唑啉酮系列化合物的合成,其中11种化合物示见文献报道。结构经元素分析,红外光谱,核磁共振氢谱和质谱确证,讨论了合成反尖条件下和质谱裂解途径,初步生理活性试验结果表明,2d和2e具有一定的生理活性。 相似文献
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Suresh Kumar Krishnammagari Byung Gwon Cho 《Phosphorus, sulfur, and silicon and the related elements》2018,193(5):306-316
Synthesis of 2-amino-4H-chromen-4-ylphosphonate derivatives has been accomplished by the one-pot three-component reaction of salicylaldehyde, malononitrile/ethylcyanoacetate and dialkyl phosphites in the presence of reusable deep eutectic solvent (DES) under mild conditions. The advantages of this method are mild reaction conditions, simple work-up procedure, use of DES as a green solvent and an economical protocol for the preparation of important biologically active phosphorus-containing compounds. 相似文献
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The partial molar enthalpies of mixing of NaHSO4 and KHSO4 have been measured at 528 K by dropping samples of pure compounds into molten mixtures of NaHSO4 and KHSO4 in Calvet calorimeter. From these values the molar enthalpy of mixing has been deduced.
The same method has been used for the determination of the heat capacity of the two pure compounds in the solid and liquid
states.
The phase diagram of this system has been confirmed by conductometric and thermal analysis methods.
By an optimization method the excess entropy of the liquid mixtures was also calculated.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds.In contrast to 3 or 5-aryl pyrazole,the preparation of 4-aryl pyrazole is fairly rare.Utilizing microwave irradiation,the synthesis of 4-substituted-arylpyrazole via Suzuki cross-coupling has been developed with a wide range of substrates.The remarkable advantages of this method are mild reaction conditions,simple operation,high yield,and short reaction time.Product structures were identified by MS 1H NMR 13C NMR,and elemental analysis. 相似文献
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使用INDO/CI程序计算了含金属-金属多重键的钼原子簇化合物Mo2I4(NCR)4(R=Me,Et,Ph)体系的电子光谱,所得波数及强度与实验符合.在谱带指认分析中,除看到已知的δd→δd*跃迁外,还看到了新的金属多重键具有的πd→σp-s(M)跃迁.说明R=Me,Et,Ph次序变化的取代基效应引起的体系第一吸收带红移.对Mo≡Mo键的性质也进行了讨论. 相似文献
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用2-硫代-3-正丁基-5-苯基亚甲基4-咪唑啉二酮的-S-烷基化反应合成了2-烷硫基-3-正丁基-5-苯基亚甲基-4H-咪唑啉-4-酮衍生物。探讨了S-烷基化反应的反应条件和所合成化合物的波谱性质。目标产物均为新的化合物,其结构经元素分析,IR,1H NMR和MS确正。 相似文献
10.
Charles H. Langley Jenn‐Huei Lii Norman L. Allinger 《Journal of computational chemistry》2001,22(13):1396-1425
Aliphatic aldehydes have been studied with the aid of the MM4 force field. The structures, moments of inertia, vibrational spectra, conformational energies, barriers to internal rotation, and dipole moments have been examined for six compounds (nine conformations). MM4 parameters have been developed to fit the indicated quantities to the wide variety of experimental data. Ab initio (MP2) and density functional theory (B3LYP) calculations have been used to augment and/or replace experimental data, as appropriate. Because more, and to some extent, better, data have become available since MM3 was developed, it was anticipated that the overall accuracy of the information calculated with MM4 would be better than with MM3. The best single measure of the overall accuracy of a force field is the accuracy to which the moments of inertia of a set of compounds (from microwave spectroscopy) can be reproduced. For all of the 20 moments (seven conformations) experimentally known for the aldehyde compounds, the MM4 rms error is 0.30%, while with MM3, the most accurate force field presently available, the rms error over the same set is 1.01%. The calculation of the vibrational spectra was also improved overall. For the four aldehydes that were fully analyzed (over a total of 78 frequencies), the rms errors with MM4 and MM3 are 18 and 38 cm?1, respectively. These improvements came from several sources, but the major ones were separate parameters involving the carbonyl carbon for formaldehyde, the alkyl aldehydes and the ketones, and new crossterms featured in the MM4 force field that are not present in the MM3 version. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1396–1425, 2001 相似文献
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A simple synthesis of novel and known calix[4]resorcinarenes derivatives has been achieved by the condensation of resorcinol and different aromatic aldehydes in the presence of catalytic amounts of Fe3O4 nanoparticles under solvent-free conditions.The experimental conditions have been thoroughly optimized and established,allowing significant rate enhancements and good to excellent yields.The reactions can be run safely without using any toxic organic solvents under mild reaction conditions.The Fe3O4 nanoparticles were characterized by powdered X-ray diffraction(XRD),transmission electron microscopy(TEM) and FT-IR spectroscopy. 相似文献
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以对称二氨基硫脲为原料,与冰醋酸反应生成5-甲基-4-氨基-1,2,4-三唑-3-硫酮(1);在弱酸性条件下,1与取代水杨醛反应生成席夫碱中间体5-甲基-4-(N-取代邻羟苯基)亚胺基-1,2,4-三唑-3-硫酮(2a~2c);最后在碱性条件下分别与N-取代苯基-2-氯乙酰胺发生烷基化反应生成15种未见报道的目标化合物3-(N-取代苯基-2-乙酰胺基)硫基-4-(N-取代邻羟苯基)亚胺基-5-甲基-1,2,4-三唑(3a~3o),其结构经IR,1H NMR,13C NMR确证.初步生物测试表明,质量分数为0.01%时,3a~3o对白色念珠菌的抑菌率均达90%以上,具有很强的抑菌活性;对金黄色葡萄球菌、大肠杆菌的抑菌率达80%以上,具有较强的抑菌活性. 相似文献
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On the basis of the calculated atomic polar tensors the generalized atomic polar tensor charges have been calculated for 4-isopropylphenol (4-IP) and related compounds: benzene, quinone, phenol and p-nitroaniline (p-NA). The second order Möller–Plesset perturbation method and Huzinaga–Dunning's double valence ζ basis set supplemented by d polarisation function on heavy atoms and p on hydrogen atoms (D95V**) have been used. Analysis of the atomic charges has been done. It is found that the phenyl rings of the 4-IP and p-NA molecules have an intermediate structure between the aromatic ring and the quinoid one. 相似文献
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Yulia M. Sadykova Larisa M. Sadikova Alena V. Zalaltdinova Yulia K. Voronina Alexander R. Burilov Michael A. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):705-710
AbstractThe reaction of 4-chloro- and 4-bromoresorcinol with 2-ethoxyvinylphosphonic acid dichloroanhydride has been investigated for the first time. It has been determined that the product of the reaction is the mixture of structural isomers of bicyclic phosphonates at the ratio of 9:1. The structure and composition of the compounds have been elucidated from 1H, 31P, and 13C NMR spectroscopy, mass-spectrometry (MALDI-TOF), as well as elemental and X-ray analysis. 相似文献
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A convenient method for the synthesis of condensed tricyclic pyridines using intramolecular cyclization of 4-arylpyridines is reported. The tricyclic compounds, 2-azafluorenone (9), 2-azafluorenone (10), 2-azafluorenol (11), lactones 12 and 13, and anhydride 14 have been prepared. 相似文献
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Stancho Stanchev Frank Jensen Ilia Manolov 《International journal of quantum chemistry》2008,108(8):1340-1351
4‐Hydroxycoumarins are compounds with a lot of applications as drugs and herbicides. They have very interesting spectral and chemical properties, which are investigated theoretically and experimentally. Some new 4‐hydroxycoumarins with arylydene‐β‐ketoester or arylydene‐2,4‐pentanedione side chain were synthesized by two step synthetic scheme. Their structure was characterized by UV–vis, IR, and 1H NMR methods. The spectral behavior of the optimized structures of these compounds was reproduced by the hybrid DFT methods B3LYP and B3P86 with 6‐31G** and aug‐cc‐pVDZ basis sets. Electronic excited states and vibrational frequencies were calculated. HF method was also used for comparison, because of the lack of electronic correlation. The theoretical spectra were compared with the experimental ones. A lot of compounds show good agreement between experimental and some of the theoretical data, especially obtained by aug‐cc‐pVDZ basis set. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献
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由溶胶-凝胶法制得的Ni-La化合物经热分解制备了纳米尺度NiLa2O4尖晶石,在750 oC焙烧后形成了结晶良好的尖晶石结构.采用差热分析、X射线衍射、透射电镜、扫描电镜和粒度分布分析等手段表征了该尖晶石的物理化学性质.结果表明,该纳米颗粒有规则的外形和确定的晶面,由平均粒径为40 nm的规整半球晶粒组成.精修的晶胞参数a=3.861205?和c=12.6793?.在NaBH4选择还原亚胺制相应仲胺的反应中,该新型纳米NiLa2O4尖晶石可用作高效多相催化剂,得到了较高的产物产率.所有反应可在室温和相对较短的时间内完成.在优化的反应条件下,均可得到带有不同芳基的,包括带有吸电子和供电子基团的仲胺.该催化剂回收简便,重复使用4次,其催化活性未见明显下降. 相似文献
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Jian Ping LI* Ping LIU Yu Lu WANG College of Chemistry & Environmental Science Henan Normal University Xinxiang Key Laboratory of Environmental Science Technology of High Education of Henan Province Xinxiang 《中国化学快报》2003,14(7)
Azo compounds are widely utilized as analytic reagents and dyes1, they can also be used in material of non-linear optics, material of optics information storing in laser disks, and dyes with oil solubility in photochromy in modern technology2. Recently, many noteworthy studies have shown that some azo compounds possess excellent optical memory and photoelectric properties3,4. For example, polymer scaffolds bearing azobenzene-potential are useful for optical information storage, azo-dye doped… 相似文献
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Sara Mahdjoub Muhammet Yildirim Sihem Lakehal Houssem Boulebd Abdelmadjid Debache 《合成通讯》2013,43(18):2366-2381
AbstractA simple and efficient protocol for one-pot three-component synthesis of structurally diverse dialkyl 2-amino-3-cyano-4H-chromen-4-ylphosphonates from the condensation of salicylaldehydes, malononitrile, and trialkyl phosphite using silver nanoparticles as catalyst in ethanol at reflux has been developed. Selected new compounds were evaluated for their antioxidant activity by free radical screening using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Among the compounds employed, 5a, 5?b, and 5?h showed promising DPPH radical scavenging activities compared to the experimental standards at low concentration (100?µg/mL) after 24?h incubation. 相似文献