共查询到20条相似文献,搜索用时 15 毫秒
1.
The isomeric structures of(E)-1-[4-(2-hydroxy-5-methoxybenzylideneamino)-phenyl] ethanone(I) and(E)-1-[4-(2-hydroxy-4-methoxybenzylideneamino) phenyl]ethanone(Ⅱ) ,both C16H15NO3,have been determined using X-ray diffraction techniques and characterized by IR,and their molecular structures have also been optimized at the B3LYP/6-31G(d,p) level using density functional theory(DFT) . The energetic behaviors of the title compounds in solvent media have been examined using B3LYP method with the 6-31G(d,p) basis set by applying the polarizable continuum model(PCM) . The total energies of the title compounds decrease with the increasing polarity of the solvent. In addition,DFT calculations of the title compounds' molecular electrostatic potentials(MEP) were performed at the B3LYP/6-31G(d,p) level of theory. X-ray study shows that the title compounds both have strong intramolecular O-H…N hydrogen bonds. The molecules of Ⅰ are linked into a one-dimensional framework structure by C-H…π interactions,while in Ⅱ,intermolecular π···π interactions result in the formation of infinite chains running along the [010]. 相似文献
2.
2,5-二取代-1,3,4-噻二唑具有杀虫、杀菌、除草、调节植物生长以及药理活性等多种功效[1-5],因而该类化合物的研究迄今仍方兴未艾.近年来,很多文献报道含芳环或芳杂环的席夫碱化合物具有很高的生物活性,因而也引起人们的高度重视[6,7].由于氟原子具有模拟效应、电子效应等特殊性质,氟原子与含氟基团的引入有时可使化合物的生物活性倍增,近年也公认含氟化合物对环境的影响最小[8].鉴于不同活性的基团在同一分子中聚集能明显改善化合物的生物活性这一特性,本文将二-(4-氟苯)甲基引入到1,3,4-噻二唑Schiff碱类化合物中,以期实现活性的叠加,有可能发现新型生物活性更好的化合物.该类化合物的合成一般采用常规加热法,但具有反应时间长,收率不高,溶剂使用量大等缺点. 相似文献
3.
4.
5.
A. R. Jalilian M. Sheikhha M. Mirzaei G. R. Aslani A. Shafiee 《Journal of Radioanalytical and Nuclear Chemistry》2004,260(2):373-377
5-[2-(2-Chlorophenoxy)phenyl]-1,3,4-oxadiazole-2-yl-4-fluorobenzoate 6a, the non-classic benzodiazepine ligand, has been shown to elicit a significant anticonvulsant activity against pentylenetetrazole-induced
convulsion. In order to perform biological studies, we decided to prepare the [18F]-labeled compound. This compound was prepared in no-carrier-added (n.c.a) form from 5-[2-(2-chlorophenoxy)phenyl]-1,3,4-oxadiazole-2-yl-4-N,N,N-trimethylanilinium
triflate 5 in one step at 125 °C in Kryptofix 2.2.2/[18F] and DMSO as the solvent followed by column chromatography. The synthesis took 20 minutes with an overall radiochemical
yield of 70-75% (EOS) and a specific activity about 74 GBq/mmole and chemical-radiochemical purity more than 95%.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
以芳甲酰肼和对硝基苯甲酰氯为主要原料, 合成出了10个酰氨基硫脲化合物5a~5j, 其中有6个(5d, 5f~5j)为新化合物. 在无需任何酸性催化剂条件下, 将制得的酰氨基硫脲在DMF中加热回流直接脱水关环合成出了9个2-芳基-5-(4-硝基苯甲酰氨基)-1,3,4-噻二唑化合物6a~6i, 其中7个(6b~6d, 6f~6i)为新化合物. 利用IR和1H NMR证明了化合物5存在两种异构体. 目标产物的结构通过IR, 1H NMR和元素分析进行了表征. 相似文献
7.
8.
2,5-二[4-(2-芳基乙烯基)苯基]噁二唑的合成及发光特征 总被引:6,自引:0,他引:6
二乙烯联苯及其衍生物是一种可发射蓝光的小分子空穴型有机发光材料, 通过Wittig-Horner反应, 将电子传输型噁二唑环“嵌入”其中, 设计合成了6个2,5-二[4-(2-芳基乙烯基)苯基]-1,3,4-噁二唑化合物. 经光谱分析和元素分析等方法确认了它们的化学结构. IR和UV-vis分析数据表明标题化合物分子结构中的C=C双键均为反式结构特征. 研究结果表明: 2,5-二[4-(2-对二甲氨基苯基乙烯基)苯基]-1,3,4-噁二唑具有良好的蓝色发光性能; 取代基对标题化合物的UV-vis吸收光谱和发光特性的影响显着. 相似文献
9.
Ravinaik B. Rao M. V. B. Rao P. T. S. R. K. P. Ramachandran D. Reddy D. R. S. 《Russian Journal of Organic Chemistry》2021,57(4):624-630
Russian Journal of Organic Chemistry - A series of substituted N-(4-{5-[4-(5-methyl-1,3,4-oxadiazol-2-yl)phenyl]-4-(2,3,4-trimethoxyphenyl)-1,3-thiazol-2-yl}phenyl)benzamides were designed... 相似文献
10.
It has been shown by1H NMR spectroscopy that hydrazones obtained by the condensation of hydrazides of [5-4-pyridyl)-1,3,4-oxadiazol-2-ylthio] acetic or 2-[5-(2-pyridyl)-1,3,4-oxadiazol-2-ylthio]propionic acids with aldehydes, ketones, and -dicarbonyl compounds exist in DMSO solution as a mixture of stereoisomeric forms.Institute of Chemistry, Vilnius LT-2600, Lithuania. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 966–971, July, 2000. 相似文献
11.
12.
Daniel E. Lynch 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1201-1203
The structures of 2-amino-5-methyl-1,3,4-thiadiazole, C3H5N3S, and 2-amino-5-ethyl-1,3,4-thiadiazole, C4H7N3S, have been determined for comparison with unsubstituted 2-amino-1,3,4-thiadiazole. Despite their different space groups (P21/n and Pbca, respectively), the packing modes of the methyl and ethyl derivatives are similar, with comparable three-dimensional hydrogen-bonding associations. This is in contrast to the hydrogen-bonding network in 2-amino-1,3,4-thiadiazole, which is one-dimensional and has denser packing. It is shown that both packing forms are different polymorphs of a specific subunit of each array. 相似文献
13.
Zarghi A Hajimahdi Z Mohebbi S Rashidi H Mozaffari S Sarraf S Faizi M Tabatabaee SA Shafiee A 《Chemical & pharmaceutical bulletin》2008,56(4):509-512
A new series of 2-substituted-5-[2-(2-halobenzyloxy)phenyl]-1,3,4-oxadiazoles was designed and synthesized as anticonvulsant agents. Electroshock and pentylenetetrazole-induced lethal convulsion tests showed that the introduction of an amino group at position 2 of 1,3,4-oxadiazole ring and a fluoro substituent at ortho position of benzyloxy moiety had the best anticonvulsant activity. Our results showed that this effect is mediated through benzodiazepine receptors mechanism. 相似文献
14.
4-Amino-3-(p-chlorophenyl)-5-(p-methoxybenzyl)-4H-1,2,4-triazole:X-ray and DFT-calculated Structures
The title compound, 4-amino-3-(p-chlorophenyl)-5-(p-methoxybenzyl)-4H-1,2,4- triazole I , C16H15ClN4O), has been determined using X-ray diffraction techniques and the molecular structure has also been optimized at the B3LYP/6-31 G(d, p) level using density functional theory (DFT). The triazole ring exhibits dihedral angles of 41.61(15)o and 80.73(11)o with the phenyl rings. The molecules are linked principally by N–H…N hydrogen bonds involving the amino NH2 group and a triazole N atom, forming C(5) chains which are further linked to give a two-dimensional network of molecules. The N–H…N hydrogen bonding is supported by C–H…N hydrogen bond and C–H…π interaction. Intermolecular N–H…N and C–H…N hydrogen bonds produce R22(9), R44(10) and R44(20) rings. 相似文献
15.
16.
Synthesis and Structure of 2-Isobutyl-6-(2'''',4''''-dichlorophenyl)imidazo[2,1-b]-1,3,4-thiadiazole 总被引:1,自引:0,他引:1
1INTRODUCTIONThethiadiazoleandimidazolecompoundsareextensivelystudiedduetotheirspectrumbioacti-vities[1~4].Amongthem,theimidazo[2,1-b]-1,3,4-thiadiazolederivativesarepharmaceuticallyimpor-tantbecauseoftheirimmunostimulant[5],antifugal[6],antimicrobial[7]… 相似文献
17.
18.
19.