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1.
张光  张林林 《分析化学》1997,25(1):79-81
报道以5-(5-硝基-2-吡啶偶氮)-2,4-二氨基甲苯(5-NO2-PADAT_作为测定钌的分光光度法。在40%乙醇存在下PH4.0-6.5乙酸-乙酸钠缓冲溶液中5-NO2-PADAT与Ru(Ⅱ)形成稳定的红色络合物。该络合物的无机酸作用下,可转变为另一型人有较高吸收特性的络合物,适宜酸度范围分别为0.12-2.0mol/LHCl,0.12-1.2mol/LHClO4,0.12-1.0mol/L  相似文献   

2.
应用离子淌度谱仪在负高压方式下测得苯酚、2-氯代酚、2,4-二氯代酚及五氯代酚的折合淌度值分别为2.12、2.01、1.93、1.74 cm2V-1s-1,检测限分别为 1.0、0.1、0.5、0.5μg/L,2-氯代酚、2,4-二氯代酚的二聚体的折合淌度值分别为 1.60、1.47cm2V1s1,并对苯酚、2-氯代酚和2,4-二氯代酚的混合物进行了分析测定,并讨论了淌度值与分子量、分子形状之间的关系。  相似文献   

3.
萘普生及其酯类的手性分离和光学纯度测定   总被引:1,自引:1,他引:0  
以磺化β- 环糊精作为手性分离添加剂, 分别对萘普生、萘普生甲酯和萘普生氯乙酯进行了毛细管电泳手性分离研究, 当以含40 g/L 的磺化β- 环糊精的0 .010 mol/L 的三羟甲基氨基甲烷- 柠檬酸为缓冲液(pH5.0) 时,上述3 种化合物的手性分离度分别为2 .19 、2 .60 和1 .99 。 手性化合物的出峰时间和校正峰面积的相对标准偏差分别为2 .84 % 和6 .26% , 而两对映体的相对出峰时间和相对校正峰面积的相对标准偏差分别为0 .52 %和1 .86 % 。 对萘普生和萘普生氯乙酯的实际样品进行了光学纯度测定, 测定结果与HPLC 进行了比较。  相似文献   

4.
几种挥发性有机酚的离子淌度谱研究   总被引:1,自引:1,他引:0  
郭岩  陆妙琴 《分析化学》1997,25(8):951-954
篱子淌度谱仪在负高压方式下测得苯酚、2-氯代酚、2,4-二氯代酚及五氯代酚的折合淌度值分别为2.12、2.01、1.93、1.74cm^2V^-1s^-1,检测限分别为1.0、0.1、0.5、0.5μg/L,2-氯代酚、2,4-二氯代酚的二聚体折合沿度值分别为1.60、1.47cm^2V^-1S^-1,并对苯酚、进行了分析测定,并讨论了淌度值与分子量,佞子形状之间的关系。  相似文献   

5.
甲基安非他明及杂质的气相色谱/质谱分析   总被引:5,自引:0,他引:5  
张银华  陈华 《分析化学》1998,26(12):1464-1467
利用DB-5弹性石英毛细管柱气相色谱/质谱联用技术分析公安人员缴获非法生产甲基安非他明粗产品,其中含有甲基安非他明83%,及主要杂质1-苯基丙酮13.36%和2-甲亚胺基-1-基基丙烷1.33%。此外还检测到 了甲基安非他明的分解产物1-丙烯基苯0.11%、2-丙烯基苯0.03%和环丙基苯0.01%等。据此我科可以判断,该甲基安非他明是从1-苯基丙酮和甲胺反应再经催化氢化合而得。  相似文献   

6.
用^H NMR方法测定了交联度分别为10%,7.%,5%,2.5%,1%,0.5%及0.25%4 丙烯酰胺-丙烯酸与N,N‘-亚甲基双丙烯酰胺交联共聚水凝胶中水及主链质子的化学位移谱及自旋晶格驰豫时间T1,并用BBP模型进行了讨论。  相似文献   

7.
离子对高效液相色谱法分析注射用新灭菌   总被引:1,自引:1,他引:1  
建立了离子对高效液相色谱法分离与测定复方制剂(新灭菌)中的羟氨苄青霉素及氟氯青霉素含量法。采用C8.10μm,4.6×200mm柱(大连化物所Spherisorb),以含1.4%十六烷基三甲基溴化铵的pH6.5磷酸盐缓冲液-乙腈(68+32)为流动相,在紫外检测器254nm波长处检测,线性范围为0.25~2mg/mL,r=0.9999(n=5),羟氨苄青霉素及氟氯青霉素平均回收率分别为99.5%及100.7%(n=5)。精密度:羟氨苄青霉素及氟氯青霉素日内(4h)平均RSD(相对标准偏差)均为0.8%(n=15),日间(2h)平均RSD分别为0.6%和0.7%(n=3)。  相似文献   

8.
5—Br—PADAP快速光度法测定钢中铌   总被引:4,自引:0,他引:4  
研究了用2-(5-溴-吡啶偶氮)-5-二乙氨苯基酚(5-Br-PADAP)测定钢中铌显色条件,所拟方法简捷实用,可测钢中0.010%~6.00%的铌。  相似文献   

9.
研究了反应物配料比3-AMP/Cl(摩尔比)、反应温度与时间对大孔型3-氨甲基吡啶树脂(3—AMPR)性能的影响规律.在最佳合成工艺条件下制得3-AMPR的功能基含量为3.16mmol/g树脂.3-AMPR对AuCl6(2-),PtCl6(2-),IrCl6(2-),PdCl4(2-),RhCl6(3-)的吸附容量分别为800.8,387.8,386.3,133.0,105.5mg金属/g树脂;配位比分别为1.29,0.63,0.64,0.40,0.33。比较了3—AMPR、2-AMPR、4-氨基吡啶树脂(4-APK)、3—APR、2-APR五种树脂对AuCl4-、PtCl6(2-)的吸附性,其中3-AMPR为最佳。  相似文献   

10.
五种含氨基及吡啶基功能性聚合物,2,6-二氨基吡啶树脂(DAPR),2-氨基甲基吡啶树脂(2-AMPR),2-氨基吡啶树脂(2-APR),3-氨基吡啶树脂(3-APR),4-氨基吡啶树脂(4-APR)对Ir(Ⅳ)和Ru(Ⅳ)的最佳吸附酸度均为0.1molHCl/L,对Ir(Ⅳ)的吸附容量分别为1200、786、480、500和381mgIr(Ⅳ)/g树脂,其吸附摩尔比(离子/功能基)分别为2.11  相似文献   

11.
Reaction of dichloro‐ and dibromodimethyltin(IV) with 2‐(pyrazol‐1‐ylmethyl)pyridine (PMP) afforded [SnMe2Cl2(PMP)] and [SnMe2Br2(PMP)] respectively. The new complexes were characterized by elemental analysis and mass spectrometry and by IR, Raman and NMR (1H, 13C) spectroscopies. Structural studies by X‐ray diffraction techniques show that the compounds consist of discrete units with the tin atom octahedrally coordinated to the carbon atoms of the two methyl groups in a trans disposition (Sn? C = 2.097(5), 2.120(5) Å and 2.110(6), 2.121(6) Å in the chloro and in the bromo compounds respectively), two cis halogen atoms (Sn? Cl = 2.4908(16), 2.5447(17) Å; Sn? Br = 2.6875(11), 2.7464(9) Å) and the two donor atoms of the ligand (Sn? N = 2.407(4), 2.471(4) Å and 2.360(5), 2.455(5) Å). In both cases, the Sn? N(pyridine) bond length is markedly longer than the Sn? N(pyrazole) distance. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

12.
3-amino-4,6-dimethyl-2-ethylseleno[2,3-b]pyridine carboxylate (5) was prepared by a reaction of dipyridyl diselenide derivative (3) with sodium borohydride as a reducing agent followed by α-haloester. The reaction of 5 with hydrazine hydrate afforded the corresponding carbohydrazide 8. The benzylidene derivative 9 provided novel heterocycles of pyrimidoseleno pyridine and thiazinoseleno pyridine derivatives (10–12), upon treatment with triethylorthoformate, acetic anhydride, and carbon disulfide, respectively.  相似文献   

13.
Quaternization of poly(4-vinyl pyridine), (P4-VP) by common alkyl halides can be performed with relatively low (up to 65–70%) conversion yields. Here we describe fully quaternization of P(4-VP) with activated halides such as chloro 2-propanone and 2-chloroacetamide in dimethylformamide (DMF) at room temperature.  相似文献   

14.
Experiments were performed to determine whether F- and CF3-substituted pyridines undergo quaternization with iodomethane (1:1 molar ratio in THF) and 1,3-diiodopropane (2:1 molar ratio in MeCN). 2-Fluoropyridine and 2-(trifluoromethyl)pyridine did not react with MeI even under prolonged reflux, while 3-fluoropyridine, 3,5-difluoropyridine, 3-(trifluoromethyl)pyridine and 4-(trifluoromethyl)pyridine gave methiodide salts in 28-72% yield. 2-Fluoropyridine did not react with I(CH2)3I, 3-fluoropyridine gave the bis-quaternary salt and 3,5-difluoropyridine yielded a mono-quaternary derivative. Both 3- and 4-(trifluoromethyl)pyridine furnished the bis-quaternary products in 53 and 55% yield, respectively. The bis-quaternary salts are potentially useful in the treatment of organophosphorus nerve agent poisoning.  相似文献   

15.
Cyanothioacetamide ( 1 ) reacted with but‐2‐enal ( 2 ) to give the corresponding 4‐methyl‐2‐sulfanylpyridine‐3‐carbonitrile ( 7 ) which was used as a good starting material for the synthesis of 1‐(3‐amino‐4‐methylthieno[2,3‐b]pyridin‐2‐yl)ethan‐1‐one ( 10 ), 3‐amino‐4‐methylthieno[2,3‐b]pyridine‐2‐carboxamide ( 15 ), 3‐amino‐4‐methylthieno[2,3‐b]pyridine‐2‐carboxylate ( 18 ) and 3‐amino‐4‐methylthieno[2,3‐b]pyridin‐2‐ylarylketone 25a‐c through its reactions with each of (1‐chloroacetone ( 8 ), 3‐chloropentane‐2,4‐dione ( 11 ) or ethyl 2‐chloro‐3‐oxo‐butanoate ( 19 )), 2‐chloroacetamide ( 13 ), ethyl 2‐chloroacetate ( 16 ) and 2‐bromo‐1‐arylethan‐ 1 ‐one 23a‐c , respectively. Considering the data of elemental analyses, IR, 1HNMR, mass spectra and theoretical calculations, structures of the newly synthesized heterocyclic compounds were elucidated.  相似文献   

16.
New pyridine, pyrazoloyridine, and furopyridine derivatives substituted with naphthyl and thienyl moieties were designed and synthesized starting from 6-(naphthalen-2-yl)-2-oxo-4-(thiophen-2-yl)-1,2-dihydropyridine-3-carbonitrile (1). The chloro, methoxy, cholroacetoxy, imidazolyl, azide, and arylamino derivatives were prepared to obtain the pyridine-C2 functionalized derivatives. The derived pyrazolpyridine-N-glycosides were synthesized via heterocyclization of the C2-thioxopyridine derivative followed by glycosylation using glucose and galactose. The furopyridine derivative 14 and the tricyclic pyrido[3′,2′:4,5]furo[3,2-d]pyrimidine 15 were prepared via heterocyclization of the ester derivative followed by a reaction with formamide. The newly synthesized compounds were evaluated for their ability to in vitro inhibit the CDK2 enzyme. In addition, the cytotoxicity of the compounds was tested against four different human cancer cell lines (HCT-116, MCF-7, HepG2, and A549). The CDK2/cyclin A2 enzyme inhibitory results revealed that pyridone 1, 2-chloro-6-(naphthalen-2-yl)-4-(thiophen-2-yl)nicotinonitrile (4), 6-(naphthalen-2-yl)-4-(thiophen-2-yl)-1H-pyrazolo[3,4-b]pyridin-3-amine (8), S-(3-cyano-6-(naphthaen-2-yl)-4-(thiophen-2-yl)pyridin-2-yl) 2-chloroethanethioate (11), and ethyl 3-amino-6-(naphthalen-2-yl)-4-(thiophen-2-yl)furo[2,3-b]pyridine-2-carboxylate (14) are among the most active inhibitors with IC50 values of 0.57, 0.24, 0.65, 0.50, and 0.93 µM, respectively, compared to roscovitine (IC50 0.394 μM). Most compounds showed significant inhibition on different human cancer cell lines (HCT-116, MCF-7, HepG2, and A549) with IC50 ranges of 31.3–49.0, 19.3–55.5, 22.7–44.8, and 36.8–70.7 μM, respectively compared to doxorubicin (IC50 40.0, 64.8, 24.7 and 58.1 µM, respectively). Furthermore, a molecular docking study suggests that most of the target compounds have a similar binding mode as a reference compound in the active site of the CDK2 enzyme. The structural requirements controlling the CDK2 inhibitory activity were determined through the generation of a statistically significant 2D-QSAR model.  相似文献   

17.
以2,6-二氯吡啶为起始原料,经甲氧基化、硝化、氨基化、还原及成环5步反应得到2-巯基-5-甲氧基咪唑并[4,5-b]吡啶,总收率45.7%。重点比较了2-氯-6-甲氧基吡啶和2,6-二氯吡啶硝化反应条件及收率的差异,讨论了水合肼、NaOH的用量对目标产物收率的影响。用1HNMR、MS和IR测试技术对目标产物结构进行了表征。  相似文献   

18.
洪新  李云赫  高畅  范博  庞宇莹  张丹  唐克 《燃料化学学报》2018,46(10):1184-1192
合成了一系列不同硅铝比的ZSM-5分子筛,采用XRD、FT-IR、ICP、SEM、NH_3-TPD和N_2吸附-脱附等方法对其进行了表征,研究了不同硅铝比ZSM-5分子筛对模拟柴油中苯胺和吡啶的吸附脱除性能。结果表明,所合成的ZSM-5分子筛均具有典型MFI结构;与合成原料混合物中的硅铝比相比,实际硅铝比稍有降低。ZSM-5分子筛的酸量随硅铝比的增加而降低,硅铝比较小的ZSM-5(1)和ZSM-5(2)的吸附脱除苯胺或吡啶的效果明显优于其他样品,并且所有样品吸附脱除吡啶的效果均优于苯胺。ZSM-5(2)上苯胺和吡啶的吸附等温线符合Langmuir-Freundlich混合模型。  相似文献   

19.
Cancer is one of the main global health problems. In order to develop novel antitumor agents, we synthesized 3,4-dihydropyrimidine-2(1H)-one (DHPM) and 2,6-diaryl-substituted pyridine derivatives as potential antitumor structures and evaluated their cytotoxic effects against several cancer cell lines. An easy and convenient method is reported for the synthesis of these derivatives, employing cobalt ferrite (CoFe 2 O 4 @SiO 2 -SO 3 H) magnetic nanoparticles under microwave irradiation and solvent-free conditions. The structural characteristics of the prepared nanocatalyst were investigated by FTIR, XRD, SEM, and TGA techniques. In vitro cytotoxic effects of the synthesized products were assessed against the human breast adenocarcinoma cell line (MCF-7), gastric adenocarcinoma (AGS), and human embryonic kidney (HEK293) cells via MTT assay. The results indicated that compound 4r (DHPM derivative) was the most toxic molecule against the MCF-7 cell line (IC 50 of 0.17 μg/mL). Moreover, compounds 4j and 4r (DHPM derivatives) showed excellent cytotoxic activities against the AGS cell line, with an IC 50 of 4.90 and 4.97 μg/mL, respectively. Although they are pyridine derivatives, compounds 5g and 5m were more active against the MCF-7 cell line. Results showed that the candidate compounds exhibited low cytotoxicity against HEK293 cells. The kinesin Eg5 inhibitory potential of the candidate compounds was evaluated by molecular docking. The docking results showed that, among the pyridine derivatives, compound 5m had the most free energy of binding (–9.52 kcal/mol) and lowest Ki (0.105 μM), and among the pyrimidine derivatives, compound 4r had the most free energy of binding (–7.67 kcal/mol) and lowest Ki (2.39 μM). Ligand-enzyme affinity maps showed that compounds 4r and 5m had the potential to interact with the Eg5 binding site via H-bond interactions to GLU116 and GLY117 residues. The results of our study strongly suggest that DHPM and pyridine derivatives inhibit important tumorigenic features of breast and gastric cancer cells. Our results may be helpful in the further design of DHPMs and pyridine derivatives as potential anticancer agents.  相似文献   

20.
王立升  张森  刘华文  李东  刘旭 《合成化学》2016,24(7):582-586
以2-甲基吡啶为原料,经氧化、硝化、还原反应合成了重要中间体4-氨基-2-甲基吡啶(3); 3分别经1,4-加成反应、Heck反应及取代反应合成了11个吡啶类化合物(4~14),其中5, 6和8~14为新化合物,其结构经1H NMR, 13C NMR, MS和HR-MS进行表征。  相似文献   

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