可见光催化氮杂环丙烯与马来酰亚胺的[3+2]环加成反应

本文报道了在可见光照射下,以10-甲基-9-均三甲苯基吖啶高氯酸盐为光催化剂,室温条件下实现了氮杂环丙烯与马来酰亚胺[3+2]环加成反应,以55-99%的产率合成了二氢吡咯[3,4-c]吡咯-1,3(2H,3aH)二酮类化合物。此外,向反应体系中加入DDQ,可一锅法得到芳构化的吡咯[3,4-c]吡咯-1,3(2H,5H)二酮。该方法具有操作简单、反应条件温、官能团耐受性好等特点。     

具有对称结构的吡咯并[3,4-b]喹啉-1-酮衍生物的超声辅助合成及荧光性能

以6-氯-2-氯甲基-3-喹啉甲酸乙酯(1)为底物,在无水乙醇中经超声辅助下分别与对苯二胺(2)和联苯二胺(3)中的两个氨基反应,得到具有对称结构的吡咯并[3,4-b]喹啉-1-酮衍生物(4,5).所合成的化合物未见文献报道,其结构经红外光谱、核磁共振氢谱、核磁共振碳谱和高分辨质谱得以确定.对化合物4和化合物5及过去报道的化合物6a-l进行荧光光谱测定,结果表明化合物4和化合物5及化合物6a-g具有较好的荧光性能.     

含取代吡咯连均三唑环的芳(氧)酰胺类化合物的合成及除草活性测定

10种未见文献报道的N-[3-(3,4-二甲基-2-吡咯基)-5-巯基-4-均三唑基]-取代芳(氧)酰胺类连杂环化合物通过将5-取代苯基-2-呋喃甲酸及取代苯氧乙酸经酰化后, 分别与3-(3,4-二甲基-2-吡咯基)-4-氨基-5-巯基-1,2,4-三唑在乙腈中反应而合成制得. 结构经元素分析、IR和¹H NMR得到确证. 生物活性测试结果表明: 大部分目标化合物具有一定的除草活性.     

新型吡咯并三嗪酮类PARP-1抑制剂的设计、合成及生物活性

分别以5-溴-2-氟苯甲腈(1a)和3-溴苯甲腈(1b)为原料,经Sonogashira偶联,脱三甲基硅基保护基,三分子偶联及水解等5步反应制得中间体2-氟-5-［(4-氧代-3,4-二氢吡咯［1,2-d］［1,2,4］三嗪-1-基)甲基］苯甲酸（6a)和3-[(4-氧代-3,4-二氢吡咯［1,2-d］［1,2,4］三嗪-1-基)甲基］苯甲酸（6b）。环烷基甲酸经酰氯化,缩合和脱Boc保护基3步反应制得环烷基哌嗪-1-基甲酮(7a~7c)。 6a与NCS（1 eq.）反应制得5-［(6-氯-4氧代-3,4二氢吡咯［1,2-d］［1,2,4］三嗪-1-基)甲基］-2氟 苯甲酸(6c); 6a与NCS(2 eq.)反应制得5-［(6,7-二氯-4氧代-3,4二氢吡咯［1,2-d］［1,2,4］三嗪-1-基)甲基］-2氟-苯甲酸(6d)。 6a~6d, 6a~6c分别与7a~7c和1-（2-嘧啶基）哌嗪在TBTU（缩合剂）,DIPEA（碱）的作用下合成了13个新型吡咯并三嗪酮类PARP-1抑制剂(8a~8m),其结构经¹HNMR和MS(ESI)表征。采用Alarm blue法研究了8a~8m对肿瘤细胞MDA-MB-436的抑制活性(IC₅₀)。结果表明：8f, 8g, 8i和8j对MDA-MB-436有较强的抑制活性（IC₅₀=30.5~69.3 nmol·L^-1）。     

5-甲基-4-[3-氯-4-(3-氟苄氧基)苯氨基]吡咯并三嗪-6-甲酸乙酯的合成及其抗肿瘤活性

以3-甲基-2-氰基吡咯-4-甲酸乙酯为原料,采用新的路线,经3步反应合成了5-甲基-4-[3-氯-4-(3-氟苄氧基)苯氨基]吡咯并[2,1-f][1,2,4]三嗪-6-甲酸乙酯。通过对其合成过程中的反应条件优化,使反应收率得以提高,三步反应总收率26.4%。借助核磁共振、质谱等检测手段对反应中间体和目标化合物进行了结构表征。通过对人系肿瘤细胞SW480、A549和A431生长抑制活性实验,表明所得目标化合物能够选择性抑制肿瘤细胞A431的增殖(IC50:2.62±1.82μM)。     

3-取代苯基吡咯吡嗪酮的合成

以2-甲基-3-对氨基苯基吡咯并[1,2-a]吡嗪-1(2H)-酮为母体,分别经酰基化(或磺酰基化,烷基化)反应合成了一系列新型的吡咯并吡嗪酮类化合物,其结构经1H NMR,IR和MS表征。     

一种新型α-甲醚基吡咯的合成

以乙酰乙酸苄酯(4)为原料, 经Knorr缩合制备了2,4-二甲基-3-丙酸甲酯基-5-羧酸苄酯基-1-氢吡咯 (2) 和2,4-二甲基-3-羧酸甲酯基-5-羧酸苄酯基-1-氢吡咯(3)。乙醚介质中,溴水氧化条件下,吡咯 (2) 发生自身缩合生成二吡咯甲烷 (7),吡咯 (3)无反应发生。在Pb(OAC)₄氧化条件下,当其浓度为吡咯 (3)浓度的2倍时,在80 ℃,吡咯 (3) 完全转华。所得产物经HCl甲醇溶液回流,以82%的产率制备了新型2-甲氧基甲基-3-羧酸甲酯基-4-甲基-5-羧酸苄酯基-1氢吡咯 (1)。吡咯(1)、(2)、(3)及二吡咯(7)的结构用核磁、元素分析、质谱和红外等测试技术进行了表征。吡咯(1)的构建对进一步研究吡咯构效关系具有一定参考价值。     

3-乙酰基取代吡咯衍生物的合成及其晶体结构

本文通过Knorr合成法制备了四个3-位乙酰基取代的吡咯衍生物:1, 2-二甲基-4-异丙基-5-苯基-3-乙酰基-吡咯(5a); 1, 2, 4-三甲基-5-对甲氧苯基-3-乙酰基-吡咯(5b); 1, 2, 5-三甲基-4-苯基-3-乙酰基-吡咯(5c); 1, 2, 5-三甲基-4-对甲氧苯基-3-乙酰基-吡咯(5d)。通过红外, 质谱, 核磁等方法对其结构进行了表征。测定了其中三个化合物的晶体结构。对这类吡咯环上4或5-位有芳环取代基时化合物的晶体结构特征进行了扼要讨论, 晶体衍射实验结果表明,4, 5-位上的芳环与吡咯环本身处于非共平面结构。     

新型吡咯季铵盐的合成

以乙酰乙酸乙酯为原料,经缩合、氧化、还原和氯代等反应合成了3-甲基-5-碘甲基-1H-吡咯-2,4-二(甲酸乙酯)(5);5分别与乌洛托品,吡啶和三甲胺经取代反应合成了3个吡咯季铵盐6a~6c,其中5和6a~6c均为新化合物,其结构经1H NMR,IR和ESI-MS表征。     

新型N-取代-R-氧基羰基-1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺的无溶剂合成

在无溶剂条件下,1,6-亚甲基桥[10]轮烯-3,4-二甲酸酐与尿素反应制得1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺(2);2与KOH的甲醇溶液于常温反应得1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺钾(3);3与氯甲酸酯反应合成了4个新型的N-酯基取代的1,6-亚甲基桥[10]轮烯-3,4-二甲酰亚胺,其结构经1H NMR,13C NMR,IR,MS和HR-MS表征。     

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%.     

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.     

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

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.