5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的新法合成

以2,6-二氯吡啶为起始原料,经肼基化、还原、硝化、Nietzki-Dietschy环合4步反应得到5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物.结合反应机理讨论了还原、硝化、Nietzki-Dietschy环合反应的影响因素,获得了合成-.氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的最佳工艺条件,目标产物的总收率为59.2%.用1H NMR、MS和IR谱对5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的结构进行了表征.     

5-取代氧化呋咱并[3,4-b]吡啶衍生物的合成与表征

以廉价易得的2,6-二氯吡啶为原料,经过硝化、叠氮化、热解环化步骤得到中间体[1,2,5]噁二唑并[3,4-e]四唑并[1,5-a]吡啶-3-氧化物(4b),再与浓硫酸/硝酸钾、甲醇钠和甲胺水溶液反应分别得到5-取代的氧化呋咱并[3,4-b]吡啶衍生物5~7。 研究了化合物4b结构的稳定性,发现其中的氧化呋咱环在强酸性、强碱性和弱碱性条件下较稳定,而吡啶环与叠氮基形成的四唑环结构则不太稳定。     

7-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的胺化开环反应及产物的抗肿瘤活性

7-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物(1)与胺在温和条件下反应,氧化呋咱环开环,释放一分子次硝酸,得到了蓝绿色的开环产物2-胺取代的-3-亚硝基-4-氨基-5-硝基吡啶5a~5f.发现化合物1中的6-位硝基对其氧化呋咱开环起到关键作用.利用~1H NMR,~(13)C NMR和HRMS对目标化合物进行了结构表征.用四甲基偶氮唑盐(MTT)法测试了目标化合物体外抑制人肺癌细胞株(H522)和脑胶质瘤细胞株(U87)两种肿瘤细胞的增殖活性.测试结果显示,所有目标化合物均表现较强的体外肿瘤细胞抑制活性.     

10-氯-5-二乙氧基甲基-1,3-二甲基色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮的合成和晶体结构

利用L-脯氨酸催化的5-氯水杨醛(1)与6-甲基-4-羟基吡喃酮(2)的缩合反应及硫酸铜催化下与1,3-二甲基-5-氨基吡唑(3)的串联反应,合成得到了10-氯-1,3-二甲基-5-(2-氧代丙基)色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(4)和10-氯-5-二乙氧基甲基-1,3-二甲基色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(5).化合物5的结构通过单晶X射线衍射法确定:晶体属于三斜晶系,空间群P-1;相对分子质量Mr=803.68;晶胞参数a=1.03160(10)nm,b=1.42900(13)nm,c=1.44268(15)nm;V=1.9448(3)nm~3;Z=2;晶胞密度Dc=1.372g/cm~3;吸收系数μ=0.228mm-1;单胞中电子的数目F(000)=840.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R=0.0681,w R=0.2051.在晶体结构中色烯环与吡啶环及吡唑环近似于共平面.     

改进的2-巯基-5-甲氧基咪唑并[4,5-b]吡啶合成法

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。     

5(4H)-吡啶酮并氧化呋咱及其核苷衍生物的合成及结构表征

设计了一个新化合物——5(4H)-吡啶酮并氧化呋咱(4H,5H-[1,2,5]噁二唑[3,4-b]吡啶-5-酮-1-氧化物),对它的合成方法及四乙酰核糖核苷衍生物的合成进行了研究.合成产物及中间体经1HNMR、质谱和元素分析进行了结构鉴定.     

微波辐射下硅磺酸催化的香豆素并[4,3-d]吡唑并[3,4-b]吡啶的高效合成

在硅磺酸催化下,通过微波辐射的3-酰基香豆素与5-氨基吡唑的反应,一步高产率地合成了一系列香豆素并[4,3-d]吡唑并[3,4-b]吡啶衍生物.该方法具有反应时间短(20~30 min)、选择性好、产率高、操作简单和环境友好等优点.产物的结构经红外光谱、核磁共振谱及高分辨质谱予以确定.     

4,5二氢[1,2,4]三氮唑并[4-3-a]喹林衍生物的合成

为了寻找正性肌力作用更强、副作用较小的治疗充血性心力衰竭的正性肌力药物 ,本文参照有关二氢喹啉酮类化合物的结构与正性肌力活性的文献报道[1- 5] ,在喹啉环上并入三氮唑 ,设计合成了 4,5二氢 [1 ,2 ,4]三氮唑并 [4 3 ａ]喹啉衍生物 ,以进一步探索二氢喹啉酮并入三唑环对其活性的影响。其结构经质谱、红外光谱和核磁共振氢谱表征。1　合成路线以苯胺为起始原料 ,经酰化、环合、硝化、还原、硫代、环合得 6 氨基 4,5二氢 [1 ,2 ,4]三氮唑并 [4 3 ａ]喹啉衍生物 :2　实验部分熔点用毛细管法测定 ,温度计未校正。红外光谱仪为ＦＴ ＩＲ1 …     

4-氯-2-甲基吡啶并[3,2-d]嘧啶的合成

吡啶并嘧啶类衍生物具有较好的生物活性,4-氯-2-甲基吡啶并[2,3-d]嘧啶是一种重要的医药中间体,已报道的合成方法成本较高且操作繁琐,不适合工业化生产.本文以2-氯-3-硝基吡啶为起始原料,经取代、还原、环合等5步反应得到目标化合物,产物结构经1 H NMR,13C NMR和MS确证,总收率为33％.该路线具有成本...     

嘧啶并呋咱核苷衍生物的制备及其活性初探

4H,6H-[1,2,5]噁二唑并[3,4-d]嘧啶-5,7-二酮1-氧化物(1)和6-甲基-4H,6H-[1,2,5]噁二唑并[3,4-d]嘧啶-5,7-二酮1-氧化物(2)是一氧化氮(NO)供体, 将它们分别在无溶剂条件下与高温熔融的全乙酰基保护的核糖、木糖、葡萄糖进行糖基化反应, 分别得到相应的噁二唑并[3, 4-d]嘧啶核苷类化合物7, 9～12, 化合物7经NH₃-MeOH处理, 去O-乙酰基制得8, 这些新型核苷化合物可作为潜在的NO供体. 部分此类化合物的生物活性研究表明, 嘧啶并呋咱核苷衍生物具有抗病毒、抗肿瘤活性, 为研究抗病毒、抗肿瘤药物提供了新结构类型的候选化合物.     

Helic[6]arene-Based Chiral Pseudo[1]rotaxanes and [1]Rotaxanes

Chiral pseudo[1]rotaxanes and [1]rotaxanes constructed from macrocyclic arenes still remain a big challenge mainly owing to the lack of such chiral macrocycles. In this work, a new system of chiral pseudo[1]rotaxanes formed by self-inclusion of helic[6]arene containing amide linked with the terminal tertiary amines was first discovered. Based on an atom-economic stopping strategy, a pair of chiral [1]rotaxanes were conveniently obtained in almost quantitative yields by blocking the pseudo[1]rotaxanes with monobenzyl bromide of tetraphenylethene. The structures of pseudo[1]rotaxanes and [1]rotaxanes were characterized by 2D NMR spectra in solution, combined with DFT calculations. The photophysical properties further revealed the efficient chirality transfer of helic[6]arene to the tetraphenylethene moiety, compared to their unthreaded chiral isomers. The discovery of the chiral pseudo[1]rotaxanes allows for a wide and available synthesis of chiral [1]rotaxanes, and also opening a new avenue to the design of chiral supramolecular materials.     

Spectrophotometric study of the supramolecular complexes of [60]- and [70]Fullerenes with biscalix[6]arene and crown[4]calix[6]arene

[60]- and [70]Fullerenes have been shown to form 1:1 supramolecular complexes with bis[2-(5,11,17,23,29,35-hexa-tert-butyl-37,38,39,40,41-pentahydroxycalix[6]arenyl-oxy ethyl ether) (1) and 5,11,17,23,29,35-hexa-tert-butyl-37,38,40,41-tetra hydroxyl-39,42-(crown-4)calix[6]arene (2) in CHCl3 medium by electronic absorption spectroscopy. Formation constants (K) of the complexes of [60]- and [70]fullerenes with 1 and 2 have been determined at room temperature from which free energy of formation values of the complexes have been estimated. The very high formation constant value of [60]fullerene/1 complex (5900 dm3 mol-1) in indicative of formation of inclusion complex. Moreover, PM3 calculations reveal that intermolecular interaction between [60]fullerene and 1 proceeds through quite deep energy molecular orbital.     

One-pot synthesis of oxygen and nitrogen-bridged calix[2]arene[2]triazines

A simple and powerful one-pot reaction method was developed for the synthesis of heteracalixaromatics. In the presence of a base, one-pot macrocyclic condensation reaction between cyanuric chloride and 1,3-phenylene diols and diamines proceeded effectively under very mild conditions to afford a number of functionalised oxygen and nitrogen-bridged calix[2]arene[2]triazines in 33–54% yields. The method was applied in a multigram-scale (14.4 g) preparation of tetraoxacalix[2]arene[2]triazine.     

Monofunctionalized pillar[5]arene-based stable [1]pseudorotaxane

A new monofunctionalized pillar[5]arene bearing imidazolium moiety that formed stable [1]pseudorotaxane even at high concentration (100 mmol/L) was reported. [1]Rotaxane was obtained effi ciently through thiol-ene reaction from [1]pseudorotaxane which further confi rmed the formation of [1]pseudorotaxane.     

Cucurbit[5]uril, Decamethylcucurbit[5]uril and Cucurbit[6]uril. Synthesis, Solubility and Amine Complex Formation

A simple way to prepare cucurbit[5]uril is described. The macrocycles of the cucurbituril type are nearly insoluble in water. The solubilities of cucurbit[5]uril, decamethylcucurbit[5]uril and cucurbit[6]uril in hydrochloric acid, formic acid and acetic acid of different concentrations have been investigated. Due to the formation of complexes between cucurbit[n]urils and protons the solubility increases in aqueous acids. The macrocyclic ligands are able to form complexes with several organic compounds. Thus, the complex formation of the cucurbituril macrocycles with different amines has beenstudied by means of calorimetric titrations. The reaction enthalpy gives noevidence of the formation of inclusion or exclusion complexes. ¹H-NMR measurements show that in the case of cucurbit[5]uril and cucurbit[6]uril the organic guest compound is included within the hydrophobic cavity. Decamethylcucurbit[5]uril forms only exclusion complexes with organicamines. This was confirmed by the crystal structure of the decamethylcucurbit[5]uril-1,6-diaminohexane complex.     

Synthesis and self-assembly of novel calix[4]arenocrowns: formation of calix[4]areno[2]catenanes

A series of novel calix[4]arenocrowns 1a-c were efficiently synthesized by a one-pot reaction of calix[4]monohydroquinone diacetate 5 with ditosylate 6 and its analogues in the presence of sodium hydroxide. It was found that the calix[4]arenocrowns could form stable pseudorotaxane-type complexes 2a-c with paraquat, and further self-assemble into calix[4]areno[2]catenanes 3a-c with dicationic salt 8 and p-bis(bromomethyl)benzene.     

Synthesis and Characterization of Boron Complex of Calix[4]arene

IthasbeenshownthatcalixarenescanperformselectiveiontranspoFtandformneutralcomplexeswithcanonsthroughprotonlossl.Olmsteadreported'thesynthesisandXraycrystalstructuresofTitanium(IV),Iron(ill)andCobalt(II)complexesofp-tertbutylcalix[4]areneandfoundthatacompleteexchangeofallfourOHgroupsinp-lertbutylcalix[4]arenetookplacewhentreatedwithTi(NMe=).togivethearyloxocomplex[{Ti(p-lerl-butylcalix[4]arene)},]'6whichmaybeformallydescribedasacentrosymmetrictitaniumaryloxidedimerconsistingoftwoTi(P-lerl…     

Synthesis and Conformational Properties of Bis（calix [4] arene）

The bis(calix [4] arene)3 was synthesized in moderate yield by the reaction of p-tert-butylcalix [4] arene (1) with 1,4-bis(chloromethyl) benzene (2). The conformation of all alkylated product 4 was investigated by the variable-temperature ^1H-NMR.     

新型杯[4]芳烃衍生物的合成

以对叔丁基杯[4]芳烃为起始原料,通过一步或两步取代反应合成了对叔丁基杯[4]芳烃的衍生物(1和2),其结构经FT-IR,^1H NMR,FAB-MS表征．     

Construction of a hetero pseudo[2]rota[2]catenane

A novel ammonium template containing three ammonium sites was synthesized. Two ammoniums located on the linear component served as template for cucurbit[6]uril to form the CB-based pseudo[2]rotacane while another one located on the macrocyclic component played a role of template for clipping reaction. As a result of a ‘‘threading-followed-by-clipping' approach, a novel hetero pseudo[2]rota[2]catenane was successfully constructed.