几种咔唑衍生物(有机光导材料)的13C核磁共振谱的研究

我们测定了3-溴咔唑,3,6二溴咔唑,9-(2',3'-环氧丙基)咔唑,9-(2',3'-环氧丙基)-3-溴咔唑和9-(2',3'-环氧丙基)-3,6-二溴咔唑(后分别简称化合物1,2,3,4,5)的宽带去偶谱、偏共振谱和非去偶谱。通过对它们的¹³C核磁共振谱的数据分析比较,就以下几方面进行了归纳总结:①信号的归属方法;②环氧丙基的¹³C化学位移范围;③偶合常数的范围,这些归纳总结有助于确定此类化合物的价键特征和结构。     

3-氨基-6-(2-(4-吡啶基)乙烯基)-9-丁基咔唑的合成及性质

通过咔唑的烷基化、硝化、碘化、Heck偶联反应、水合肼还原,设计合成了一种新型D-π-A结构的咔唑衍生物3-氨基-6-(2-(4-吡啶基)乙烯基)-9-丁基咔唑(L)。化合物的结构通过红外、核磁氢谱、碳谱和质谱等技术手段的表征。通过测定在不同溶剂中的紫外、荧光、循环伏安和理论计算,初步研究了化合物L的光学、电化学性质和电子结构。研究结果表明,化合物L的紫外吸收光谱和荧光发射光谱随着溶剂极性的增加发生不同程度的红移。     

双阳离子咔唑衍生物与DNA相互作用的光谱研究

合成了一种新型的双阳离子咔唑衍生物3,6-双(1-羟乙基-4-烯基吡啶)咔唑碘盐(3,6-BHVC), 并对其进行了表征. 利用紫外-可见吸收光谱、圆二色谱、单光子和双光子荧光发射光谱探讨了该化合物与DNA的结合方式. 所有光谱测试结果表明, 该化合物在[磷酸根]/[染料]比值较低的条件下主要以插入方式与DNA结合, 在该比值较高的条件下主要以沟槽结合方式为主. 表明咔唑衍生物可以成为一种探索具有高结合能力双光子DNA探针的基本结构.     

痂囊腔菌素A与咔唑化合物间的光致电子转移

研究了咔唑、咔唑-9-乙酸、3-溴-咔唑-9-乙酸在缺氧条件下对天然苝醌化合物痂囊腔菌素A(简记为EA)的荧光猝灭行为;由竹红菌甲素(HA)和乙素(HB)的荧光寿命估算了EA在乙腈中的荧光寿命,并进而计算了三个咔唑化合物的双分子猝灭速度常数.结果表明,三个咔唑化合物在EA的可见光吸收区无光吸收,据此推测其对EA的荧光猝灭作用归因于咔唑化合物作为电子给体而EA作为电子受体的光致电子转移作用.三个咔唑化合物的Stern-Volmer猝灭常数分别为698、704和1 063L·mol-1;乙酸基对咔唑环的光致电子转移速率几乎没有影响,而溴原子取代能够增加咔唑化合物对EA的荧光猝灭程度和光致电子转移速率.此外,EA在乙腈中的荧光寿命为1.98ns,而三个咔唑化合物的双分子猝灭速率常数分别为3.52×1011,3.56×1011和5.37×1011 L·mol-1·s-1.     

9-咔唑-羧酸化合物的微波合成及其生物活性研究

9-咔唑 -羧酸化合物不但是医药[1] 、有机光导材料[2 ] 的中间体 ,而且其本身亦具有干扰素诱导能力[3] .近年来 ,我们[4 ] 应用 9-咔唑 -乙酸和丙酸作为高效液相色谱分析氨基酸、胺和醇类的衍生化试剂 .目前所合成的此类化合物很少 .近 1 5年以来 ,微波在有机合成中的应用已发展成为一个新的研究领域[5] ,许多反应已在微波炉中高产率快速地实现了 .本文采用微波辐照法快速合成了系列 9-咔唑 -羧酸化合物 3 a— 3 m,优化了反应条件 ,并测试了它们的生物活性 .反应式如下 :丷4R5丯HR3 R2R1( 1) +Br R6COOC2 H5( 2 ) 丷4R5丯R6COOHR3 R…     

新型含取代嘧啶结构的氰基丙烯酸酯类化合物的合成与除草活性研究

为了从氰基丙烯酸酯类衍生物中寻找新的活性化合物,通过活性亚结构拼接方法,设计并合成了一系列未见文献报道的新型含取代嘧啶结构的氰基丙烯酸酯类化合物.其结构均经核磁共振氢谱、碳谱和元素分析确证.初步的生物活性测试结果表明,部分目标化合物显示出较好的除草活性.在1500 g/ha剂量下,化合物9a和9b对芥菜的茎叶处理除草活性分别为90%和100%,化合物9a和9b对繁缕的茎叶处理除草活性分别为90%和100%,化合物9a和9b对小藜的茎叶处理除草效果分别为95%和100%;此外,化合物9b在750 g/ha剂量下对芥菜、繁缕及小藜茎叶处理抑制率均达100%,化合物9b在375 g/ha剂量下对芥菜、繁缕及小藜茎叶处理抑制率分别为90%,80%和90%.     

新型咔唑取代乙炔化合物的合成

分别以咔唑和2-羟基咔唑为原料,通过Sonagashira偶联反应和N-烷基化反应合成了6个新型的咔唑取代乙炔化合物:2-乙炔基-9-苄基咔唑,2-乙炔基-9-正丁基咔唑,2-乙炔基-9-正己基咔唑,3-乙炔基-9-苄基咔唑,3-乙炔基-9-正丁基咔唑和3-乙炔基-9-{4·[4·(硝基)苯基偶氮苯]氧}亚丁基咔唑,其...     

新型吲哚咔唑化合物的合成与抗肿瘤活性

设计合成了一系列吲哚咔唑结构的抗肿瘤新化合物. 通过对反应溶剂进行选择和调整, 优化了吲哚咔唑母核合成的反应条件, 使后处理更为简便. 用溴化噻唑蓝四氮唑(MTT)法对所合成的9个目标化合物进行了体外细胞毒活性测试, 结果表明, 化合物4a, 4b, 4d, 4f和4i对人结肠癌HCT116和鼠白血病P388细胞的活性均强于阳性对照ED-571, 其中化合物4f对P388细胞的活性是阳性对照的10倍.     

新型含咔唑环芳氨基乙酰腙衍生物的合成及其蛋白酪氨酸磷酸酶1B(PTP1B)抑制活性评价

为寻找新型蛋白酪氨酸磷酸酶1B (PTP1B)抑制剂,设计并合成了一系列新型含咔唑环芳氨基乙酰腙衍生物.其结构和构型用IR、~1H NMR、~(13)C NMR和2D NMR(包括~1H-~1H COSY、~1H-~(13)C HMBC和NOESY)谱及元素分析进行了确证.通过对PTP1B抑制活性的测试发现,目标化合物对PTP1B有较强的抑制作用,且大多数化合物的IC_(50)值低于阳性对照药物齐墩果酸,其中N'-(9-辛基咔唑-3-亚甲基)-2-(4-硝基苯氨基)乙酰肼(3t)活性最高,IC_(50)=(2.78±0.04)μmol/L.利用分子对接研究了化合物3t与PTP1B酶的结合情况.     

N-硝基-N，N’-二苯基脲衍生物的合成及抑菌活性

采用"一锅法"设计合成了9个N-硝基脲衍生物,收率50.2%～76.8%.通过红外光谱、核磁共振氢谱及元素分析等测试技术确证了它们的结构.初步抑菌活性测试表明,当质量浓度为50 mg/L时,各化合物对所测试菌种均表现出不同程度的抑菌活性.其中,化合物3d和3e对水稻纹枯菌的抑菌率超过50%.量化计算结果表明,分子中的脲桥是该类化合物的抑菌活性部位.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.