新型含取代噁二唑结构的吡唑肟类化合物的合成与生物活性研究

为了寻找具有较好生物活性的吡唑肟类衍生物,采用活性基团拼接方法,设计合成了一系列新型含取代噁二唑结构的吡唑肟类化合物.利用~1H NMR、~(13)C NMR和元素分析等手段确证了目标化合物的结构.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杀虫活性.当测试浓度降为100μg/m L时,3个化合物对粘虫仍具有较好的杀虫效果,杀死率分别为70%,60%和70%.另外,1个化合物在测试浓度为500μg/m L时对蚜虫也表现出一定的杀虫作用,杀死率为60%.     

鱼藤酮类衍生物的研究进展

鱼藤酮类衍生物是一类从鱼藤属等植物中提取出来的具有杀虫活性的异黄酮类化合物. 从1932年至今, 已经从植物中提取分离出47种鱼藤酮类化合物. 这一类化合物之所以具有很好的杀虫活性, 是由于对还原型烟酰胺腺嘌呤二核甘酸(NADH)的抑制作用而阻断了线粒体的呼吸. 对天然鱼藤酮类衍生物的结构、活性和合成方面的研究分别进行了概括.     

含2-(取代苯基)噁唑基的邻甲酰胺基苯甲酰胺类化合物合成及杀虫活性研究

为了研究邻甲酰胺基苯甲酰胺类化合物的杀虫活性,总结该类化合物的构效关系、合成高活性化合物,以2-氨基-3-羟基丙酸与取代2-硝基苯甲酸为原料,经过酯化反应、缩合反应、硝基还原反应、三光气缩合反应等一系列步骤,合成了29个2-(取代苯基)噁唑基的邻甲酰胺基苯甲酰胺类目标化合物,产率在30%~50%之间.根据离体杀东方粘虫活性测定实验结果可知,该类化合物对东方粘虫表现出一定的杀虫活性,其中目标化合物2-(2-溴苯基)-N-(4-氯-2-甲基氨基甲酰基-6-甲基苯基)噁唑-4-甲酰胺(11p)活性最高.通过对目标化合物的结构与杀虫活性的分析,总结出该类化合物的构效关系,筛选出了较高活性的目标化合物.     

Aspernigerin类似物的合成及生物活性研究

以天然产物Aspernigerin为先导,将Aspernigerin结构中的一个1,2,3,4-四氢喹啉基团以芳胺类化合物替代,设计合成了15个未见文献报道的Aspernigerin类似物,结构均经过1H NMR,IR和元素分析确证.初步生物活性测试表明,大部分目标化合物均表现出了一定的杀虫和杀菌活性,其中化合物2n在200μg/mL的浓度下对小菜蛾仍表现出100%的杀虫活性,优于先导Aspernigerin和对照药剂噻虫嗪;化合物2d,2e,2j,2k表现出对黄瓜灰霉病优于先导Aspernigerin的抑制活性.     

新型N-[cis-3-(2-氯-3,3,3-三氟丙烯基)-2,2-二甲基环丙烷基羰基]-N'-芳氧乙酰肼的合成与生物活性

为了寻找高效、低毒的农药先导化合物,利用cis-3-(2-氯-3,3,3-三氟丙烯基)-2,2-二甲基环丙烷酰氯(1)与芳氧乙酰肼的缩合反应,合成了12种未见文献报道的目标化合物,其结构经IR,1H NMR,MS和元素分析测试技术确证.初步的生物活性测定结果表明,部分目标化合物在100 mg/L浓度下对双子叶植物(油菜)显示出良好的除草活性;同时,部分化合物在200 mg/L浓度下对蚕豆蚜虫(Aphis fabas)显示出较好的杀虫活性.     

芳基吡唑氟尿嘧啶类化合物的设计、合成与杀虫活性研究

利用以γ-氨基丁酸(GABA)受体抑制剂芳基吡唑类杀虫剂的关键结构5-氨基-3-氰基-1-(取代苯基)吡唑为基本母核,设计、合成了26个创新结构芳基吡唑氟尿嘧啶化合物.目标化合物结构均采用1H NMR,FTIR和元素分析进行了结构确证,以小菜蛾和库蚊为靶标进行了杀虫活性测试.评价结果表明创制化合物具有优越的杀虫活性:在浓度为1000 mg·L-1时,化合物5a~5c,5e,5m及5u对库蚊具有100%的杀虫活性;在浓度为400 mg·L-1时,化合物5p对小菜蛾具有94.5%的杀虫活性.初步构效关系研究表明:苯环上取代基种类及位置等对化合物的生物活性有重要的影响.     

3-苯甲酰基-4-羟基香豆素衍生物的合成、晶体结构及其除草活性研究

利用活性叠加的原理,设计合成了带有三酮类结构的3-苯甲酰基-4-羟基香豆素衍生物.用1H NMR,13C NMR,HRMS和X-ray单晶衍射对其进行了结构鉴定.用平皿小杯法和盆栽法评价了其对双子叶植物油菜和单子叶植物稗草的抑制活性.结果显示,目标化合物表现出与香豆素相似的活性,只对油菜有很好的抑制活性,苯甲酰基的接入能一定程度上提高4-羟基香豆素对油菜的活性.部分化合物对油菜表现出良好的活性,其中,3-(2-硝基-4-甲磺酰基苯甲酰基)-4-羟基香豆素(21)对油菜根长的抑制活性好于甲基磺草酮,10 μg/mE时,抑制率能达到87.6％,但盆栽活性比甲基磺草酮差.目标化合物虽然具有与三酮除草剂类似的结构,但并不表现出明显的白化作用,具有与三酮类除草剂不同的作用模式.化合物21对双子叶植物油菜表现出很好的选择性,可以作为开发新型选择性除草剂的先导结构,继续结构优化.     

三嗪酮杀虫活性分子的合成及生物活性

为发展更加高效的三嗪酮杀虫活性分子,本文设计合成了16种氨基部分被取代的三嗪酮衍生物,并测试了其杀虫、抑菌活性。杀虫活性测试表明:在浓度为600mg·kg~(-1)时,化合物N-(苯基氧羰基)-N-(6-甲基-3-氧代-2,3-二氢-1,2,4-三嗪-4(5H)-基)氨基甲酸苯酯(3e,100%、100%、100%)的杀棉铃虫、玉米螟、粘虫活性高于吡蚜酮(20%,35%,50%)。在浓度为0.5mg·kg~(-1)时,化合物3e(60%)的杀蚊幼虫活性高于吡蚜酮(0)。抑菌活性测试表明:三嗪酮酰胺衍生物对玉米小斑病菌和西瓜炭疽病菌表现出较高的抑菌活性;而三嗪酮亚胺衍生物对小麦纹枯病菌表现出较高的抑菌活性。     

弥拜霉素类似物的合成、表征和杀虫活性研究

以弥拜霉素类似物依维菌素为原料,根据类同合成法和亚结构连接法原理,对依维菌素进行脱糖,再与相应的酰氯进行酯化、肟化反应制得两个系列弥拜霉素类似物化合物4Ia～5IId,所有目标化合物都通过核磁共振氢谱、高分辨质谱的确认,并分别对朱砂叶螨(Tetranychus cinnabarinus)、南方粘虫(Mythimna sepatara)和蚕豆蚜(Aphis fabae)进行室内杀虫活性测定,结果表明所有衍生物均表现出不同程度的杀虫活性,其中化合物4IIa和4IIb对粘虫和蚜虫表现出很高的杀虫活性.     

2,3a-二氢-苯并吡喃[4,3-c]吡唑-3-酮类衍生物的合成及其活性

为了进一步寻找新型黄酮类农药,以苯并吡喃[4,3-c]并吡唑-3-酮为先导结构,以4-氯苯甲醚为起始原料.设计合成了33种新型的2,3a-二苯并吡喃[4,3.c]吡唑-3-酮类化合物,其结构经MS,~1H NMR和元素分析确证.并对化合物7k的单晶进行了结构测定,对目标化合物进行了杀虫和杀菌活性测试.结果表明,大部分化合物显示出一定的杀菌活性和弱的杀虫活性.     

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.