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1.
Synthesis of 4-amino- and 4-hydroxy-3-(p-chlorophenyl)-valeric acids. X-ray structure of cis-4-(p-bromophenyl)-5-methyl-2-pyrrolidinone The syntheses of diastereomeric 4-amino- and 4-hydroxy-3-(p-chlorophenyl)-valeric acids and of their ring closure products (lactones and lactams), starting from 3-(p-chlorophenyl)-4-oxo-valeric acid, are described. A single-crystal X-ray structure analysis of cis-4-(p-bromophenyl)-5-methyl-2-pyrrolidinone is given. Some aspects of the biochemistry of threo-3-(p-chlorophenyl)-4-amino-valeric acid are presented.  相似文献   

2.
Searching for novel antimicrobial agents still represents a current topic in medicinal chemistry. In this study, the synthesis and analytical data of eighteen salicylanilide esters with 4-(trifluoromethyl)benzoic acid are presented. They were assayed in vitro as potential antimycotic agents against eight fungal strains, along with their parent salicylanilides. The antifungal activity of the presented derivatives was not uniform and moulds showed a higher susceptibility with minimum inhibitory concentrations (MIC) 3 0.49 μmol/L than yeasts (MIC 3 1.95 μmol/L). However, it was not possible to evaluate a range of 4-(trifluoromethyl)benzoates due to their low solubility. In general, the most active salicylanilide was N-(4-bromophenyl)-4-chloro-2-hydroxybenzamide and among esters, the corresponding 2-(4-bromophenylcarbamoyl)-5-chlorophenyl 4-(trifluoromethyl) benzoate exhibited the lowest MIC of 0.49 μmol/L. However, the esterification of salicylanilides by 4-(trifluoromethyl)benzoic acid did not result unequivocally in a higher antifungal potency.  相似文献   

3.
A rapid, simple and sensitive spectrophotometric method for the determination of some sulphanilamides is described. The method is based on the formation of blue coloured disazo dyes by the diazotization of sulphonamides viz. sulphanilamide (SA), sulphamerazine (SMR), sulphamethazine (SMZ), sulphadimethoxine (SDM), sulphamethoxazole (SMX), sulphadiazine (SDA), sulfathiazole (STZ), sulphaguanidine (SGN), sulphamonomethoxine (SMM), sulphamethoxypyridazine (SMP) in 0.5M hydrochloric acid media at ice bath followed by the azocoupling reaction with acid monoazo dye Tropaeolin O (TrO) at pH=10.5. Formed products are stable for 10h at room temperature. Effective molar absorptivities at absorbance maxima 595nm for disazo dyes were ~10(4)M(-1)cm(-1). Stoichiometric ratios of the components of disazo dyes were determined by means of mole ratio and continuous variations methods. Linear ranges for sulphanilamides determination were 0.4-14.0μgml(-1). The methods were successfully approved at suphanilamides determination in model solutions and commercial pharmaceutical preparations.  相似文献   

4.
Four new metal-organic polymeric complexes, {[Cu(mu-OH)(mu-ClPhtrz)][(H 2O)(BF 4)]} n ( 1), {[Cu(mu-OH)(mu-BrPhtrz)][(H 2O)(BF 4)]} n ( 2), {[Cu(mu-OH)(mu-ClPhtrz)(H 2O)](NO 3)} n ( 3), and {[Cu(mu-OH)(mu-BrPhtrz)(H 2O)](NO 3)} n ( 4) (ClPhtrz = N-[( E)-(4-chlorophenyl)methylidene]-4 H-1,2,4-triazol-4-amine; BrPhtrz = N-[( E)-(4-bromophenyl)methylidene]-4 H-1,2,4-triazol-4-amine), were synthesized in a reaction of substituted 1,2,4-triazole and various copper(II) salts in water/acetonitrile solutions. The structures of 1- 4 were characterized by single-crystal X-ray diffraction analysis. The Cu(II) ions are linked both by single N (1), N (2)-1,2,4-triazole and hydroxide bridges yielding one dimensional (1D) linear chain polymers. The tetragonally distorted octahedral geometry of copper atoms is completed alternately by two water and two BF 4 (-) anion molecules in 1 and 2 but solely by two water molecules in 3 and 4. Magnetic properties of all complexes were studied by variable temperature magnetic susceptibility measurements. The Cu(II) ions are strongly antiferromagnetically coupled with J = -419(1) cm (-1) ( 1), -412(2) cm (-1) ( 2), -391(3) cm (-1) ( 3), and -608(2) cm (-1) ( 4) (based on the Hamiltonian H = - J[ summation operator S i . S i+ 1]). The nature and the magnitude of the antiferromagnetic exchange were discussed on the basis of complementarity/countercomplementarity of the two competing bridges.  相似文献   

5.
《印度化学会志》2023,100(3):100931
Some new chemo-sensors (4,4'-((1E,1′E)-(2,2′-dichloro-[1,1′-biphenyl]-4,4′-diyl)bis(diazene-2,1-diyl))bis(3,5-dihydroxybenzoic acid), 4-((E)-(4-(N-(4-((E)-(4-carboxy-2,6-dihydroxyphenyl)diazenyl)phenyl)sulfamoyl)phenyl)diazenyl)-3,5-dihydroxybenzoic acid, 4-((E)-(4-((4-((E)-(4-carboxy-2,6-dihydroxyphenyl)diazenyl)-2-sulfophenyl)amino)phenyl)diazenyl)-3,5-dihydroxybenzoic acid) were synthesized. These synthesized sensors were then characterized by FTIR, TLC, UV–Visible spectrophotometry, and NMR techniques. The sensors showed the best results for detection of all type of heavy metal ions simply by changing the colour of metal ion solution and by shifting in the λmax values of sensors due to interactions.  相似文献   

6.
Multicomponent cyclocondensation of Meldrum's acid, 2-chlorobenzaldehyde, and N-(4-bromophenyl)-3-amino-3-thioxopropanamide in the presence of N-methylmorpholine afforded N-methylmorpholinium 3-[N-(4-bromophenyl)carbamoyl]-4-(2-chlorophenyl)-6-oxo-1,4,5,6-tetrahydropyridine-2-thiolate in 65% yield. When treated with dilute HCl, the thiolate easily transformed into N-(4-bromophenyl)-4-(2-chlorophenyl)-2-oxo-6-thioxopiperidine-5-carboxamide, which reacted with alkyl halides to give products of regioselective S-alkylation in high yields. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1297–1298, May, 2005.  相似文献   

7.
利用Perkin反应和Wittig反应设计并合成了两个新型的香豆素衍生物——3-(4’-溴苯基)-7-(N-辛基-3’-溴咔唑-6’-乙烯基)香豆素(6a)和3-(4’-溴苯基)-7-(4’-甲氧基苯基-1’-乙烯基)香豆素(6b),其结构经UV,1H NMR,IR,MS和荧光光谱表征。研究结果表明,6a和6b具有荧光强度大和Stokes位移(分别为115 nm和122 nm)大的特点。  相似文献   

8.
The preparation, ESR spectra, isolation, and X-ray crystallographic structure of N-(arylthio)-2-tert-butyl-4,6-diarylphenylaminyls (1) and N-(arylthio)-4-tert-butyl-2,6-diarylphenylaminyls (2) are described. The aminyls are generated by PbO(2) oxidation of N-(arylthio)-2-tert-butyl-4,6-diarylanilines and N-(arylthio)-4-tert-butyl-2,6-diarylanilines. The kinetic ESR study shows that the aminyls are quite persistent, even in the presence of oxygen, and exist in the individual radical forms. Among the seventeen aminyls prepared, N-[(4-nitrophenyl)thio]-2-tert-butyl-4,6-diphenylphenylaminyl (1b), N-[(4-nitrophenyl)thio]-2-tert-butyl-4,6-bis(4-chlorophenyl)phenylaminyl (1f), N-[(4-nitrophenyl)thio]-4-tert-butyl-2,6-diphenylphenylaminyl (2b), N-[(4-nitrophenyl)thio]-4-tert-butyl-2,6-bis(4-chlorophenyl)phenylaminyl (2h), and N-[(3,5-dichlorophenyl)thio]-4-tert-butyl-2,6-bis(4-chlorophenyl)phenylaminyl (2j) are isolated as radical crystals. The crystallographic structures of 1b and 2b are determined by the X-ray crystallographic analyses. Aminyls 1 and 2 give similar ESR spectra consisting of 1:1:1 triplets with the a(N) values of 0.921-0.948 mT. Deuteration of the phenyl groups on the anilino benzene ring gives rise to a further splitting of the nitrogen 1:1:1 triplet by the anilino meta (0.126-0.138) and phenylthiyl ortho and para protons (0.077-0.096 mT). Upon recording at high gain, one of the partly deuterated aminyls gives satellite lines due to (33)S isotopes at natural abundance from which a(33)(S) is determined to be 0.51 mT. The ESR parameters for 1 and 2 are compared with those for structurally close N-(arylthio)-2,4,6-triarylphenylaminyl and N-(arylthio)-2,4,6-tri-tert-butylphenylaminyl.  相似文献   

9.
In the current paper we describe a novel sample preparation technique termed dispersive liquid-phase microextraction for the preconcentration and determination of 2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol (dicofol) and its degradation products in water samples that includes 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichloroethene(2,4′-DDE), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane(4,4′-DDE) and 1,1,1-trichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethane (2,4′-DDT) coupled with gas chromatography mass spectrometry (GC-MS), in which a new ionic liquid 1,3-diisooctylimidazolium hexafluorophosphate abbreviated as [D(i-C8)IM][PF6] was used as extraction solvent. For each one extraction, 1.00 mL of the methanol solution containing 40 µL of the ionic liquid was sprayed into 25.00 mL of water sample. In the meantime the ionic liquid was finely dispersed into the aqueous phase and analytes were rapidly migrated into the ionic liquid. After the solution was centrifuged for 2 min at 5000 rpm, the droplets of the ionic liquid are subsided in the bottom of the conical test tube (30.0 ± 0.2 µL). Moreover, the factors relevant to extraction efficiencies were investigated and optimised including the volume of the ionic liquid, disperser solvent, extraction time, sample pH and ionic strength. Under optimal conditions, the enrichment factors of the extraction were between 550 and 725 with an extraction efficiency ranging from 66% to 87% for each different analyte. Finally, 1.0 µL of the ionic liquid collected from above extraction was injected into the injector block of GC-MS instrument for analysis. The detection limit (S/N = 3), the relative standard deviations for 2.0 µg L?1 of the standard analyte (n = 5) and linearity in a calibration range were found to be 3–8 ng L?1, 1.0–2.7% and 10–3000 ng L?1, respectively. Good spiked recoveries over the range of 92.0–13.5% were obtained. The proposed method offers the advantages of simplicity of operation, rapidity, good extraction efficiency and enrichment factor; it has been successfully applied to determination of dicofol and its degradation products in environmental water samples.  相似文献   

10.
Two new coumarin derivatives, 7-(N,N′-diethylamino)-3-(4-hydroxyphenyl)-coumarin and 7-(N,N′-diethylamino)-3-(4-bromophenyl)-coumarin, were synthesized successfully. Their structures were verified by single crystal X-ray crystallography. The UV–vis absorption and fluorescence of the compounds were discussed. The compounds exhibit strong blue emission under ultraviolet light excitation. The molecular structures, the lowest energy transitions and the UV–vis spectra of 7-(N,N′-diethylamino)-3-(4-hydroxyphenyl)-coumarin and 7-(N,N′-diethylamino)-3-(4-bromophenyl)-coumarin have been studied with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level.  相似文献   

11.
The first-order rate constants of N-acetyl-N′-phenylthiourea (1), N-benzoyl-N′-phenyl-(2a), N-benzoyl-N′-(4-nitrophenyl)-(2b), N-benzoyl-N′-(3-chlorophenyl) (2c), N-benzoyl-N′-(4-chlorophenyl) (2d), and N-benzoyl-N′-(4-methylphenyl)thiourea (2e) were measured between 423 and 500 K. The reactions were homogeneous and unimolecular with log A (s−1) = 12.0, 13.2, 13.8, 10.9, 11.8, and 12.7 and Ea kJ mol−1 = 130.3, 141.4, 134.6, 114.9, 124.1, and 141.1, respectively. The rate data gave good Hammett correlation with σo values, and ρ is 1.99 at 450 K. © 1997 John Wiley & Sons, Inc.  相似文献   

12.
为了寻找具有生物活性的新型芳香基噻唑联哌啶酰胺类先导化合物,设计并合成了15个未见文献报道的芳基噻唑联哌啶酰胺类化合物,其结构经1HNMR、13CNMR和HRMS确证,生物活性测定结果显示,部分目标化合物表现出高效的抑菌和杀虫活性,如在200μg/mL浓度下,5-(3-溴苯基)-4-甲基-2-(1-((4-硝基苯基)磺酰基)哌啶-4-基)噻唑(6b)对黄瓜霜霉病的抑菌活性为100%,优于嘧菌酯,5-(4-溴苯基)-2-(1-((4-氯苯基)磺酰基)哌啶-4-基)-4-甲基噻唑(6c)对水稻纹枯病的抑菌活性为58.86%,与嘧菌酯相当;在500μg/m L浓度下,(4-(5-(3-溴苯基)-4-甲基噻唑-2-基)哌啶-1-基)(间甲基苯基)酮(6h)对粘虫的杀虫活性为100%.  相似文献   

13.
1INTRODUCTIONThepyrazolo[3,4-b]pyridineclassofcompoundspossessmanybiologicalandpharmacologicalactivi-ties[1],suchasactiveanti-concretionmedicaments[2]aswellasactiveanti-gramnegativeandpositivebacteriaagents[3].Thereforethesynthesesofsuchcompoundshavearousedgreatattentionofalargenumberofchemists.Themostimportantsyntheticrouteisthecondensationreaction[4~11]ofamino-pyrazoleandα,β-unsaturatedcompounds.Theorganicreactionundermicrowaveirradia-tionhastheadvantagesoffastreactionspeed,shorttime…  相似文献   

14.
The interaction of 4-hydroxycoumarin with phenyl-, 2-chlorophenyl- and 4-bromophenyhydrazine hydrochlorides in the presence of triethylamine led in all cases to the corresponding 4-(arylhydrazino)-coumarins and 1-aryl-3-(2-hydroxyphenyl)-2H-pyrazolin-5-ones. 4-(Arylhydrazino)coumarins reacted with 4-chlorobenzaldehyde in the presence of piperidine acetate to give the corresponding 2-aryl-3-(4-chlorophenyl)[1]benzopyrano[4,3-b]pyrazol-4-ones. The reaction of 4-(4-bromophenylhydrazino)-coumarin with 4-chlorobenzaldehyde in the presence of piperidine acetate and an excess of piperidine gave 2-(4-bromophenyl)-5-(4-chlorophenyl)-3-(2-hydroxyphenyl)-4-(piperidinocarbonyl)pyrazole, but the reaction of phenyl- and 4-(2-chlorophenylhydrazino)coumarins with 4-chlorobenzaldehyde gave 1-aryl-5-(4-chlorophenyl)-3-(2-hydroxyphenyl)-4-(1-piperidino)carbonyl-4,5-dihydropyrazoles.  相似文献   

15.
胥杨  薛思佳  孙晋峰  方治坤  尹安琴  陈龙 《有机化学》2008,28(11):1997-2000
以5-邻氯苯基-2-呋喃甲酰氯和丙氨酸为起始原料, 通过非均相法得到N-(5-邻氯苯基-2-呋喃甲酰氨基)丙氨酸, 再与10种不同取代苯胺反应, 通过N,N’-二环己基碳二亚胺和4-二甲氨基吡啶(DCC/DMAP)偶合法设计合成了10个未见文献报道的N-(5-邻氯苯基-2-呋喃甲酰氨基)丙氨酰胺类衍生物4a~4j. 通过元素分析, 1H NMR, IR 和MS确定化合物的结构, 初步生物活性测试表明标题化合物具有一定的除草活性.  相似文献   

16.
The kinetics of the free radical copolymerization in solution of N-(4-bromophenyl)maleimide (MBPMI), N-(2, 4-dibromophenyl)maleimide (DBPMI) and N-(2, 4, 6-tribromophenyl)maleimide (TBPMI) with styrene (St), methyl acrylate (MA), methyl methacrylate (MMA) and acrylonitrile (AN) at low and high conversions were described. Some characteristic properties of the copolymers obtained, particularly their thermal behaviour were also presented.  相似文献   

17.
2,2′,4-三(2-氯苯基)-5-(3,4-二甲氧基苯基)-4′,5′-二苯基-1,1′-二咪唑(CZ-HABI)是一种高效的光引发剂,其结构通过傅里叶红外光谱仪、核磁共振仪、紫外吸收光谱进行表征.复合引发体系(PI)由光引发剂CZ-HABI、增感剂4,4′-双(二乙氨基)苯甲酮(EMK)、供氢体N-苯基甘氨酸(NPG)组成,利用实时红外(RT-IR)对该复合光引发体系进行了光聚合反应动力学研究,结果表明:在没有供氢体条件下,基本上没有引发效果,增加供氢体后,引发效率大幅增加;增加复合光引发体系用量能提高光聚合反应的双键转化率,且最大聚合速率与[PI]1/2成正比;随着光强的增强,单体的双键转化率与最大反应速率均增大;复合光引发体系引发双丙烯酸酯类单体的最终双键转化率比三丙烯酸酯类单体要高.复合光引发体系的引发效率比ITX/EDAB光引发体系的引发效率高,与1-羟基环己基苯基甲酮(184)、2-羟基-2-甲基-1-苯基-1-丙酮(1173)的引发效果相近.  相似文献   

18.
气相色谱-串联质谱法测定土壤中的有机氯农药   总被引:12,自引:3,他引:9  
贾丽娟  邓芸芸 《色谱》2008,26(6):697-703
建立了气相色谱-串联质谱测定土壤中有机氯农药的方法,同时测定了上海郊区的20个农业土壤。样品前处理包括加速溶剂萃取(弗罗里硅土池内净化)和凝胶渗透色谱净化在线浓缩。采用多反应监测模式的气相色谱-串联质谱分析有机氯农药,降低了背景干扰,提高了分析的灵敏度。在0.001~2 mg/L的质量浓度范围内,各种农药标准溶液的线性相关系数均大于0.995。分别向3种实际土壤样品中添加农药的混合标准溶液,所测定的有机氯农药的平均回收率为65.9%~140.0%,相对标准偏差为1.5%~20.3%(n=5)。有机氯农药的检出限(S/N=3)为0.1~3.0 μg/kg,定量限(S/N=10)为0.3~8.0 μg/kg。实际土壤样品的测定结果表明:六六六(1.82~3.70 μg/kg)和六氯苯(0.94~9.8 μg/kg)有少量检出,滴滴涕的检出率高达100%,其含量范围较宽(1.08~308.76 μg/kg),平均值为53.28 μg/kg,其中85%的样品中滴滴涕含量/(滴滴伊+滴滴滴)含量的比值小于1,表明滴滴涕主要来自于早期的使用  相似文献   

19.
Disazo dyes from 6-amino-1-hydroxy-naphthalene-3-sulfonic acid (J acid) were synthesized by coupling ortho-hydroxy monoazo dyes with different diazonium compounds in acid medium (dyes No 3 – 14 . A second coupling to the ortho position of the amino group was also possible with the copper complexes of o,o' -dihydroxy monoazo dyes from 8-amino-1-hydroxynaphthalene-3,6-disulfonic acid (H acid) dyes No 19 – 22 ). This is a reversal of the well known rule that the formation of disazo dyes with aminonaphthol-sulfonic acids is only practicable when an acid coupling is followed by an alkaline one. 5-Amino-1-hydroxy-naphthalene-3-sulfonic acid (M acid), which is said to form no disazo dyes, could be coupled twice with several diazonium compounds to yield disazo dyes (dyes No 24 , 26 , 27 , 29 ).  相似文献   

20.
Some new azo sulfa drugs 3-cyano-4,6-diphenyl-1-[4-(N-substituted)sulfamyl]phenylazo-2-pyridinone dyes (1-6) and 3-cyano-4,6-diphenyl-1-[4-(N-substituted)sulfamyl]phenylazo-2-pyridinethione dyes (1′-6′) were synthesized by coupling of 4-(N-substituted)sulfamylbenzene diazonium salts with 3-cyano-4,6-diphenyl-2-pyridinone and/or with 3-cyano-4,6-diphenyl-2-pyridin-ethione. The corresponding iron (1a-6a, 1′a-6′a), copper (1b-6b, 1′b-6′b) and mercury (1c-6c, 1′c-6′c) chelates wvere also prepared. All synthesized compounds were screened in vitro for antibacterial and antifungal activities.  相似文献   

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