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1.
N-(3-Azido-2-nitroxypropyl)-N-alkylnitramines andN-(2,3-diazidopropyl)-N-alkylnitramines were prepared by nitration and azidation ofN-alkyl-N-(2-hydroxy-3-chloropropyl)sulfamates andN-(3-azido-2-hydroxypropyl)-N-alkylsulfamates. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 206–208, January, 1999.  相似文献   

2.
Ab initio and semiempirical molecular orbital calculations have been applied to study the concerted and stepwise isotopic scrambling mechanisms of 2-chloroethyl methyl sulfide in the gas phase and in aqueous solution. The calculations reveal the structural details of the reactants, transition structures, and intermediates involved in this reaction and provide relative energy estimates. The concerted mechanism is found to be competitive with the stepwise mechanism in the gas phase, but the stepwise mechanism is favored in aqueous solution as no true transition structure for the concerted mechanism could be found using the solvation models. A combined approach of evaluating solvation energies with the generalized-Bom-plus-surface-tensions SM x solvation models of Cramer and Truhlar at ab initio optimized geometries is found to deliver the best agreement with experimentally determined reaction barriers. Together with the recent experimental results of McManus and co-workers, the present study provides insights into the controlling factors involved in the elementary reaction steps of sulfur mustards and a solid foundation for investigations into more complex reactions of related compounds.  相似文献   

3.
通过低温量热和热分析方法,测定了N-对甲基苯基-N′-(2-吡啶基)脲(以下简称NPMPN′2PU)的低温热容和热力学性质.通过对NPMPN′2PU进行低温量热,得到了NPMPN′2PU在80~370 K 温区的热容曲线,热容曲线光滑,没有任何热异常现象,由此实验热容数据计算出NPMPN′2PU在这段温区内的热力学数据.从DSC实验结果发现, NPMPN′2PU熔化峰值出现在173.86 ℃,熔化焓为204.45 kJ•mol-1.紧接熔化峰后NPMPN′2PU开始分解,分解峰只有一个,分解峰值温度为226.11 ℃.TG和DTG的实验结果表明,NPMPN′2PU失重的峰值为227.2 ℃,这些结果与DSC实验结果吻合.  相似文献   

4.
Two methods for the synthesis of N-(2-chloroethyl)glycine and-DL-alanine esters are proposed: 1) reductive amination of the C=O group of glyoxilic or pyruvic acids upon treatment with 2-chloroethylamine and sodium cyanoborohydride in methanol and 2) alkylation of 2-chloroethylamine with α-haloalkanoic acid esters in K2CO3-MeCN two-phase system. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2372–2374, December, 2007.  相似文献   

5.
The reactions of aminoalkylethoxysilanes and 2,2-dimethyl-1,3-dioxa-6-aza-2-silacyclooctane with 2-(chlormethyl)thiophene and its 5-chloroderivative lead to the correspondingN-(2-thenyl) derivatives. TheN-methyl-N-(2-thenyl)aminomethyltriethoxysilane and 5-chlorothyenyl derivative formed are converted by triethanolamine into silatranes.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 384–386, February, 1995.  相似文献   

6.
Heating cyclohexanespiro-2-oxazolidine at 160–200°C in the presence of protic acids results in its decomposition to giveN-(2-hydroxyethyl)cyclohexylamine,N-(2-hydroxyethyl)-4,5,6,7-tetrahydroindole, and 2-cyclohexylidenecyclohexanone. The possible pathways leading to these compounds are discussed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1547–1548, August, 1997.  相似文献   

7.
A method was developed for the preparation of functionally substituted N-nitrooxazolidines and N-nitrotetrahydro-1,3-oxazines by nitration of the products obtained in the reactions of N-(2-hydroxyalkyl)- and N-(3-hydroxyalkyl)sulfamates with formaldehyde.  相似文献   

8.
Cholesterol oxidase (ChOx), cholesterol esterase (ChEt), and horseradish peroxidase (HRP) have been co-immobilized covalently on a self-assembled monolayer (SAM) of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPTS) deposited on an indium–tin–oxide (ITO) glass surface. These enzyme-modified (ChOx-ChEt-HRP/AEAPTS/ITO) biosensing electrodes have been used to estimate cholesteryl oleate from 10 to 500 mg dL−1. The sensitivity, K m value, and shelf-life of these ChEt-ChOx-HRP/AEAPTS/ITO biosensing electrodes have been found to be 124 nA mg−1 dL, 95.098 mg dL−1 (1.46 mmol L−1), and ten weeks, respectively. The ChEt-ChOx-HRP/AEAPTS/ITO bio-electrodes have been used to estimate total cholesterol in serum samples. Figure Covalent immobilization of enzymes onto AEAPTS/ITO surface using EDC/NHS chemistry Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

9.
Previously unknown N-(2-nitroxyethyl)isonicotinamide was synthesized by the reaction of isonicotinoyl chloride with 2-nitroxyethylamine and was used as a ligand in the reactions with PdCl2 and PtCl2 to prepare new complexes, viz., trans-bis[(2-nitroxyethyl)isonicotinamide-N]dichloropalladium(ii) and cis-bis[(2-nitroxyethyl)isonicotinamide-N]dichloroplatinum(ii), respectively. The structures of the ligand and the resulting complexes were established by X-ray diffraction analysis.  相似文献   

10.
The interactions between N-(p-chlorophenyl)-N′-(1-naphthyl) thiourea and serum albumin were investigated by fluorescence spectroscopy and UV absorption spectrum under physiological conditions. The results of spectroscopic measurements suggested that N-(p-chlorophenyl)-N′-(1-naphthyl) thiourea should have a strong ability to quench the intrinsic fluorescence of both bovine serum albumin and human serum albumin through static quenching procedure, and the hydrophobic interaction was the predominant intermolecular force stabilizing the complex. Thermodynamic parameter enthalpy changes (ΔH) and entropy changes (ΔS) were calculated according to the Vant’Hoff equation. The binding distances between N-(p-chlorophenyl)-N′-(1-naphthyl) thiourea and the proteins were evaluated on the basis of the theory of Föster energy transfer. In addition, the effects of other ions on the binding constants of complexes were also discussed. Synchronous fluorescence technology was successfully applied to the determination of serum albumins added to the CPNT solution.  相似文献   

11.
Summary The solvatochromic behaviour ofbis-(cyano)-bis-(9,10-phenanthroline)-iron(II) has been reexamined spectrophotometrically in a series of 19 solvents including water, alcohols and dipolar. aprotic media. Satisfactory correlations between the wave numbers of the long-wavelength band and solvent acceptor numbers are obtained in all media; only values, for carboxylic acids deviate from the regression line.
Spektrophotometrische Untersuchungen über die Solvatochromie der Komplexverbindung Fe(CN)2(phen)2
Zusammenfassung Das solvatochrome Verhalten vonbis-(Cyano)-bis-(9,10-phenanthrolin)-eisen(II) wurde in 19 Lösungsmitteln, darunter Wasser, Alkohole und dipolare aprotische Medien, spektrophotometrisch überprüft. In allen Medien wurden zufriedenstellende Korrelationen zwischen den Wellenzahlen der langwelligen Bande und den Akzeptorzahlen der Lösungsmittel erhalten; lediglich die Werte für Carbonsäuren weichen von der Ausgleichgeraden ab.
  相似文献   

12.
2-(Alkoxycarbonylmethylidene)-4-aryl-5-(dialkylamino)thiophen-3(2H)-ones were synthesized by condensation of N,N-(dialkyl)arylthioacetamides with dialkyl acetylenedicarboxylates. Intermediate substituted vinylic sulfides were isolated. When heated or in the presence of an acid or a base, they undergo cyclization into thiophenes.  相似文献   

13.
合成了4种N-(2,4-二硝基苯基)-N -取代苯腙类阴离子结合受体(14, 取代基 R=H, o-OCH3, o-Cl, o-OH), 应用紫外吸收光谱方法研究了其与阴离子的相互作用, 以及考察N -苯环取代基对受体分子之阴离子亲合力和选择性的影响. 实验显示: 乙腈中F、CH3CO 等阴离子使受体分子吸收光谱红移, 溶液由黄色转变为红色, 其中受体分子2对 F表现出高选择性的灵敏响应. 实验表明受体-阴离子间形成了氢键型超分子配合物, Job作图法给出了受体分子与阴离子的1∶1结合计量比, 1H NMR滴定为受体分子与阴离子间的氢键作用本质提供了直接证据.  相似文献   

14.
Li D  Chang X  Hu Z  Wang Q  Li R  Chai X 《Talanta》2011,83(5):1742-1747
A new material has been synthesized using dry process to activate bentonite followed by N-(2-hydroxyethyl) ethylenediamine connecting chlorosilane coupling agent. The synthesized new material was characterized by elemental analysis, FT-IR and thermogravimetry which proved that bentonite was successfully modified. The most interesting trait of the new material was its selective adsorption for rare earth elements. A variety of conditions of the new material were investigated for adsorption. The optimal conditions were determined with respect to pH and shaking time. Samarium (Sm) was quantitatively adsorbed at pH 4 and shaking time of 2 min onto the new material. Under these conditions the maximum static adsorption capacity of Sm(III) was found to be 17.7 mg g−1. The adsorbed Sm(III) ion were quantitatively eluted by 2.0 mL 0.1 mol L−1 HCl and 5% CS (NH2)2 solution. According to IUPAC definition, the detection limit (3σ) of this method was 0.60 ng mL−1. The relative standard deviation (RSD) under optimum conditions was less than 3% (n = 8). The new material also was applied for the preconcentration of trace Sm(III) in environmental samples with satisfactory results.  相似文献   

15.
以对氨基苯酚(1)为原料,经氨基的羟乙基化、酚羟基的苄基保护、氯代、脱保护制得N,N-二 (2-氯乙基) -对氨基苯酚(5);在碳酸铯作用下,5与溴丙炔经O-烷基化反应合成了新化合物--O-炔丙基-N, N-二(2-氯乙基)-4-氨基苯酚,其结构经1H NMR, 13C NMR和MS表征。  相似文献   

16.
The reaction ofN-2-nitroxyethylpicolinamide with PdCl2 afforded the new complexcis-[2-(2-pyridyl)-2-oxazoline-N,N′]dichloropalladium(u). The structure of this complex was established by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 561–563, March, 2000.  相似文献   

17.
The non-oxidative thermal degradation of poly (di-2-chloroethyl itaconate) (PD2CEI) was studied by TG and by analysing the thermal products. The major processes occurring during thermal analysis are crosslinking, depolymerisation and carbonisation. The thermal degradation activation energy increased with increasing sample mass loss. The thermal degradation of PD2CEI was compared to that of the structurally similar poly(2-chloroethyl methacrylate) (P2CMA).  相似文献   

18.
19.
N′-(取代嘧啶-2-基)-N-菊酰硫脲的合成与生物活性研究   总被引:7,自引:0,他引:7  
采用活性基团拼接法, 将第一菊酸构型中的最高活性组分(+)-反式菊酸以及二氯菊酸引入到含取代嘧啶环的酰基硫脲结构中, 合成了5个未见文献报道的N′-(取代嘧啶-2-基)-N-(+)-反式菊酰硫脲衍生物(3a3e)和3个均未见文献报道的N′-(取代嘧啶-2-基)-N-二氯菊酰硫脲(3f3h), 结构经元素分析、IR和1H NMR得到确证. 初步的生物活性测试结果表明: 大部分化合物具有较好的杀菌活性, 有的化合物兼具除草和杀菌活性, 有的化合物兼具杀虫和杀菌活性.  相似文献   

20.
The geometric parameters, the charge distribution, and the energetics of N-methyl-2-(N-ethylanilino)-3-(indol-1-yl)-and N-methyl-2-(N-ethylanilino)-3-(indol-3-yl)maleimides and their conjugated acids were studied by density functional theory calculations at the B3LYP/6-31G(d) level. The mechanism of the tandem hydride transfer/cyclization sequence, which occurs after protonation of N-methyl-2-(N-ethylanilino)-3-(indol-1-yl)-and N-methyl-2-(N-ethylanilino)-3-(indol-3-yl)maleimides, was analyzed. The investigation of the potential energy surface for the tandem hydride transfer/cyclization of the iminium cation that formed upon protonation revealed that the hydride transfer followed by intramolecular cyclization at position 7 of the indole fragment in N-methyl-2-(N-ethylanilino)-3-(indol-1-yl)maleimide is the preferable process, unlike alternative intramolecular cyclization involving the cationic center at the C(2) atom of the indole fragment and the benzene ring of the N-ethylaniline fragment of the indoleninium cation in N-methyl-2-(N-ethylanilino)-3-(indol-3-yl)maleimide. A study of the key intermediates of the assumed reaction mechanism demonstrated that these intermediates are actually stationary points on the potential energy surface (minima and transition states). Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2069–2073, December, 2006.  相似文献   

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