NO供体型马蹄金素衍生物的合成及其初步的抗乙肝病毒活性

以马蹄金素[N-(N-苯甲酰基-L-苯丙氨酰基)-O-乙酰基-L-苯丙氨醇,MTS]为先导化合物,设计并合成了11个NO供体型马蹄金素衍生物,所有目标产物均未见文献报道,其结构经NMR,ESI-MS确认.以HepG2 2.2.15细胞为乙肝病毒载体,对合成的马蹄金素衍生物进行了抗乙肝病毒活性测试.结果表明,在测试浓度范围内,化合物6d,6e,6g具有抗HBV活性,其半数抑制浓度分别为6.88,37.51,11.07μmol/L.其中,化合物6d和6g的半数抑制浓度优于MTS(11.16μmol/L),且具有较高的抑制率,具有进一步研究开发的价值.     

新型N-甲基马蹄金素衍生物的合成及抗乙肝病毒活性

以L-苯丙氨酸甲酯盐酸盐为原料,依次经缩合、还原、甲基化和催化氢化反应制得N-甲基-L-苯丙氨醇（4）; 4依次与N-Fmoc-L-苯丙氨酸（5a）或N-Fmoc-L-酪氨酸（5b）经缩合和脱Fmoc反应制得游离氨基化合物7a或7b; 7a(7b)与多种苯甲酸衍生物反应合成了20个新型的N-甲基马蹄金素衍生物（8a～8t）,其结构经¹H NMR, ¹³C NMR和MS（ESI）表征。以2.2.15细胞模型进行了初步的抗乙肝病毒（HBV）活性评价。结果表明：化合物8n和8o显示出一定的抗HBV活性,IC₅₀分别为52.5 μmol·L^-1和49.2 μmol·L^-1。     

基于点击化学反应的半乳糖糖基化马蹄金素衍生物的合成及抗HBV活性

以D-半乳糖和二缩三乙二醇为原料,经乙酰化、糖基化和叠氮化钠取代等反应合成了带叠氮连接臂的半乳糖配基,通过点击化学反应将其与炔丙基修饰的马蹄金素(MTS)衍生物进行连接,设计合成了6个具有潜在肝靶向性的半乳糖糖基化MTS衍生物.通过1H NMR,13C NMR,1H-1H COSY,HMQC,DEPT和ESI-MS对其结构进行了表征;采用Hep G2 2.2.15细胞模型初步评价了目标化合物的抗乙型肝炎病毒(HBV)活性.结果表明,所有目标化合物对HBV DNA的复制均有抑制作用,且具有一定的量效关系;化合物15f在50μg/m L浓度下对Hep G2 2.2.15细胞株的抑制率为83%,具有进一步研究的价值.     

新型苯丙氨酸三肽衍生物的合成及其抗乙肝病毒活性

以具有抗HBV活性的苯丙氨酸二肽化合物马蹄金素(MTS)为先导化合物,设计并合成了23个新型的苯丙氨酸三肽衍生物（4a~4h, 5, 6a, 6b和8a~8k）,其结构经¹H NMR, ¹³C NMR和MS(ESI)表征。采用HepG2 2.2.15细胞为乙肝病毒载体,评价了目标化合物的抗HBV活性。结果表明：化合物5（IC₅₀=2.98 μM）、 6b（IC₅₀=0.62 μM）和8k（IC₅₀=5.07 μM）对HBV DNA复制的抑制活性优于MTS（IC₅₀=11.16 μM）。     

具有肝靶向潜力的马蹄金素衍生物合成及抗乙肝活性研究

为了提高马蹄金素(MTS)衍生物在肝脏病变部位的药物浓度,增强其抗乙肝病毒活性,设计并合成了5个半乳糖糖基化修饰的具有肝靶向潜力的MTS衍生物,通过1H NMR,13C NMR,1H-1H COSY,HMQC和ESI-MS对其进行了结构表征,并用Hep G2 2.2.15细胞模型初步评价了合成所得目标化合物的抗乙肝病毒(HBV)活性.结果表明,所有目标化合物对HBV DNA的复制均有抑制作用,且具有一定的量效关系.     

8-异戊基取代的黄酮类化合物的合成及其抑制MDA-MB-231细胞增殖的活性评价

以3,5-二甲氧基苯酚为起始原料,经5~6步反应,合成了8-异戊基取代的8个桑皮素类似物,经体外对人乳腺癌细胞MDA-MB-231增殖的抑制作用测试.结果显示:相对于槲皮素(IC50 69.3μmol/L),桑皮素具有较大的抑制活性(IC50 22.5μmol/L);将桑皮素分子结构中的稠合环醚打开,即在8位引入异戊基、且对酚羟基甲醚化可进一步提高活性(IC50 12.1μmol/L);在3位上分别引入不同大小的疏水性基团(氢、苄基、烯丙基和异戊烯基)可保持高活性;5位引入疏水性基团可能是有利的;B环对位的甲氧基对活性影响显著;最高活性化合物7g的IC50值达到8.26μmol/L.     

丁苯酞-哒嗪酮衍生物的设计、合成及其抗凝活性研究

为了提高丁苯酞的抗血小板凝集活性,以6-氨基丁苯酞为起始原料,经重氮化/还原、环化、水解、脱氯、醚化和磺酰化反应合成了20个新型的丁苯酞-哒嗪酮衍生物,其结构经1H-NMR、13C-NMR和HRMS确证。体外抗血小板凝集活性测试结果表明:化合物6a、6b和6k对二磷酸腺苷(ADP)诱导的血小板凝集的抑制活性(IC50 = 44.9-180.0 μmol/L)优于先导化合物丁苯酞(IC50 = 1252 μmol/L)和阳性对照阿司匹林(IC50 = 1140 μmol/L);同时化合物 6b(IC50 = 63.6 μmol/L)和6k(IC50 = 191.9 μmol/L)对花生四烯酸(AA)诱导的血小板凝集也表现出显著的抑制活性。本研究为丁苯酞-哒嗪酮骨架在治疗缺血性脑卒中方面的研究提供了理论参考。     

白藜芦醇衍生物的合成及抑制宫颈癌HeLa细胞肿瘤活性

以白藜芦醇、氯乙酰氯、对甲苯磺酰氯、对甲苯甲酰氯为原料,合成9种新的白藜芦醇衍生物,其结构经IR,1HNMR,13C NMR和HRMS所表征.用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法测试了目标化合物抑制宫颈癌HeLa细胞的肿瘤活性,结果表明:化合物4a,6a,7b,8b和11c对HeLa细胞的抑制活性比白藜芦醇高,其中化合物6a和8b的抑制效果最明显,其IC50值分别为22.7和18.0μmol/L,活性高于白藜芦醇(IC50=114μmol/L),且在150μmol/L浓度下对HeLa细胞的抑制率达95.5%和87.7%.     

N_(12)-乙基取代吲哚咔唑衍生物的合成及细胞毒活性研究

合成了9个新的N12-乙基取代吲哚咔唑衍生物6~14,其结构经1H NMR、13C NMR和HRESIMS确定.用噻唑蓝(MTT)法测试了衍生物对人肺癌细胞A549、肝癌细胞Hep G-2和宫颈癌细胞Hela的细胞毒活性.用细胞计数试剂盒-8(Cell Counting Kit-8,CCK-8)法测试了衍生物对白血病细胞K562的细胞毒活性.结果显示,化合物7~9对K562的细胞毒活性与阳性对照阿霉素(ADM)相近,半数抑制浓度(IC50)为0.43~0.93μmol/L.化合物8和12对Hela的活性与阳性对照相近,IC50分别为1.23和0.43μmol/L.化合物13的盐酸盐14对所测试的4种肿瘤细胞株均有较强的抑制活性,IC50值在0.23~1.72μmol/L之间,可作为抗肿瘤先导化合物进行深入研究.     

吡喃半乳糖糖基化马蹄金素衍生物的合成及抗乙肝病毒活性研究

为提高马蹄金素(MTS)衍生物的肝脏药物浓度,增强其抗乙型肝炎病毒(HBV)活性.通过以乙醇胺为连接臂将具有肝靶向性的半乳糖配基与MTS进行间接连接,设计合成了5个肝靶向MTS衍生物,通过~1H NMR,~(13)C NMR,~1H-~1H COSY,HMQC和ESI-MS对其进行了结构表征,并用Hep G2 2.2.15细胞模型初步评价了合成所得目标化合物的抗乙肝病毒活性.结果表明,所有目标化合物对HBV DNA的复制均有抑制作用,且具有一定的量效关系.     

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.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

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.     

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.     

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.     

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.