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1.
In reaction of trifluormethyl-containing 1,3-diketones with oxalyl chloride 5-substituted 4-(trifluoracetyl)furan-2,3-diones were synthesized, reaction of which with azomethines resulted in 4-substituted 5-hydroxy-5-(trifluormethyl)dihydrofuran-2,3-diones.  相似文献   

2.
Abstract

The synthesis of a new set of 2,3,4,5-substituted isoxazolidines having a sulfur containing heterocyclic moiety has been described. The structural features of the compounds have been analyzed by 1H and 13C NMR spectroscopy as well as by single crystal X-ray studies.

[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: .cif file.]  相似文献   

3.
以5-取代-3,4-二卤-2(5H)-呋喃酮为底物进行Sonogashira偶联反应, 考察了反应温度、反应时间、钯催化剂种类与用量、碱种类与用量、溶剂、底物结构等对偶联反应的影响, 合成了28种新的2(5H)-呋喃酮衍生物, 其结构用IR, 1H NMR, 13C NMR, MS和元素分析等方法进行了表征. 在优化的反应条件下, 即反应溶剂为甲苯、催化剂为3 mol% Pd(PPh3)4和10 mol% CuI、碱为6 equiv. KF、反应时间72 h、反应温度30 ℃时, 反应产率42%~84%. 利用该Sonogashira偶联反应合成新型的多官能团烯二炔结构化合物, 不仅合成途径简捷、反应条件温和, 绝大部分反应产率中等以上, 而且无需额外加入配体, 适用于芳香的和脂肪的末端炔烃.  相似文献   

4.
5.
Arylhydrazones were obtained by the reaction of arylhydrazines with -(N-acylamino)acetophenones and were converted into 3-(N-acylamino)-2-phenylindoles with substituents at positions 1, 5, 6, and 7 by Fischer cyclization.  相似文献   

6.
In the reaction of N,N-dialkyl-dichloromethaniminium chlorides 11 with 2-aminoacetophenones 12 , a general and simple route to heretofore unknown 5-aryl-substituted 2-(dialkylamino)-1,3-oxazolium salts 13 and 5-aryl-substituted 2-(dialkylamino)oxazoles 14 was found. From the 2-(dialkylamino)-1,3-oxazoles 14 , the corresponding oxazolium salts 13 were obtained after alkylation with (MeO)2SO2. The new oxazolium salts 13 were converted to 1-substituted 4-aryl-2-(dialkylamino)-1H-imidazoles 9 by treatment with NH4OAc. The possible use of these 1H-imidazoles as dye educts was explored. Analytical data, as well as AM1 calculations, reveal some remarkable differences between the structures of the neutral imidazoles 9 and their positively charged oxazolium precursors 13 .  相似文献   

7.
8.
史艳萍  陈宝泉  麻静  刘玉明  李彩文 《化学学报》2011,69(21):2561-2566
根据活性基团拼合原理, 用2-氯硒基苯甲酰氯和2-氨基-5取代-1,3,4-噻二唑缩合合成了10个新的2-(2-取代- 1,3,4-噻二唑-5-基)-苯并异硒唑-3(2H)-酮衍生物(6), 并通过IR, 1H NMR, ESI-MS和元素分析对其结构进行了确认, 采用CCK-8法测试了化合物抑制肿瘤细胞增殖活性. 结果表明, 化合物6h对人体肺癌细胞A-549, 化合物6a, 6b, 6d, 6e, 6f, 6g, 6h, 6j对人体乳腺癌细胞MCF-7, 化合物6a, 6b, 6d, 6e, 6f, 6g对人体肝癌细胞SSMC-7721抑制活性均强于阳性对照药依布硒啉, 且表现出一定的选择性, 具有进一步研究的潜在价值.  相似文献   

9.
10.
本文研究了3,5-diCl-PADMA与钯的显色反应。在0.5~4.8mol/L HClO_4溶液中,试剂与钯形成稳定的1:1配合物,其最大吸收波长为616nm,表观摩尔吸光系数为8.38×10~4L·mol~(-1)·cm~(-1)。大量的铜、钴、镍及一定量贵金属离子不干扰钯的测定。所拟方法直接应用于含钯样品的分析。  相似文献   

11.
12.
5—Br—PNPFF与镍(Ⅱ)的显色反应及其分析应用   总被引:1,自引:0,他引:1  
研究了新试剂1-(5’-溴-2’-吡啶基)-5-(4’-硝基苯基)-3-(2’-呋喃基)甲■(5-Br-PNPFF)与镍(Ⅲ)的显色反应条件。在吐温-80存在下,pH5.0的邻苯二甲酸氢钾-氢氧化钠缓冲介质中,镍(Ⅲ)与5-Br-PNPFF形成1:2的深绿色配合物,其最大吸收峰在7 10nm处,ε_(710)=4.89×10~4 L/mol.cm~(-1)。选择性好,镍含量在0~300μg/L范围内符合比尔定律。用所拟方法测定钢铁中的微量镍,结果满意。  相似文献   

13.
Russian Journal of General Chemistry - A series of semicarbazones have been obtained from 2-substituted 5-acetylfurancarboxylic acid esters. When oxidized with selenium dioxide in acetic acid,...  相似文献   

14.
15.
冯泳兰 《分析化学》2000,28(3):311-313
研究了1-(2-羟基-3,5-二硝基苯基)-3-[4(苯基偶氮)苯基]-三氮烯(HDNPAPT)试剂与汞离子的显色反应。在非离子表面活性剂TritonX-100存在下,pH10.3的NH3·H2O-NH4Cl介质中,汞与HDNPAPF形成1:4的红色络合物,表观摩尔吸光系数ε525=1.63×105·mol-1·cm-1,汞离子浓度在0~0.64mg/L范围内符合比尔定律。方法应用于废水中微量汞的测定。  相似文献   

16.
A number of 1-substituted 3-(2-aminoethyl) indoles were prepared, in one step, by alkylation of the corresponding 3-(2-aminoethyl)indoles (tryptamines) in the presence of NaH.  相似文献   

17.
3-(2-Quinolyl)- and 3-(5-carbethoxyfuryl-2)coumarins were prepared by reaction of substituted salicylaldehydes and hetarylacetonitriles. Alkylation and acylation of 3-hetaryl-7-hydroxycoumarins were studied. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 432–434, September–October, 2005.  相似文献   

18.
研究了试剂2_(5_溴_2_吡啶偶氮 )_5_二甲氨基苯胺 (5_Br_PADMA)与铱 (Ⅲ )的显色反应 ;在 pH4.75~6.00的HAc -NaAc缓冲溶液中 ,铱 (Ⅲ )与5_Br_PADMA形成摩尔比为1∶2型稳定的红色络合物 ,在0.6mol/LH2SO4溶液中 ,其最大吸收波长为558nm ,表观摩尔吸光系数为5.1×104L/(mol·cm) ,铱 (Ⅲ )含量在0~0.8mg/L范围内符合比尔定律 ,采用加入适量EDTA的方法消除了Fe3 + 、Co2 + 、Ni2 + 等干扰离子 ,建立了在二元络合物体系中测定微量铱 (Ⅲ )的灵敏度高、选择性好、简便、稳定的分光光度法  相似文献   

19.
合成了 1 -(4 -硝基苯基 ) -3 -(5-硝基 -2 -吡啶 ) -三氮烯 ,并研究了它与汞(Ⅱ )的显色反应。在TritonX -1 0 0的存在下 ,pH1 1 2的Na2 B4 O7-NaOH缓冲溶液中 ,试剂与汞生成 2∶1型桔黄色配合物 ,在 4 3 8nm和 52 5nm处分别有一正一负两个吸收波峰 ,用双峰双波长测定 ,其表观摩尔吸光系数为 2 1× 1 0 5L·mo1 1·cm 1,Hg2 +的浓度在 0~ 2 80 μg/L范围内符合比耳定律。成功地测定了人发和尿液中微量的汞。  相似文献   

20.
5-Substituted tetrazoles readily react with trifluoroacetic anhydride at 20–25°C to give the corresponding 2-substituted 5-trifluoromethyl-1,3,4-oxadiazoles, in contrast to published data according to which the title compounds are converted into 1,3,4-oxadiazole derivatives on heating with carboxylic acid anhydrides or chlorides at 100–120°C. The reaction is governed not only by the rate of acylation of the tetrazole ring and temperature conditions but also by the stability of intermediate N-acyltetrazoles.  相似文献   

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