79 resultados para Nutlin-3a


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本论文由三章组成。第一、二章分别报道钩藤、蹄叶橐吾的化学成分研究工作。从两种药用植物中共分离和鉴定了37 个化合物,其中有1 组6 个新的骨架相似的鞘糖脂类同系物及5 个新的倍半萜类化合物。第三章概述了艾里莫芬烷内酯类化合物的研究进展。 第一章报道钩藤(Uncaria rhynchophylla)带钩茎枝乙醇提取物的化学成分。采用正、反相硅胶柱层析等分离方法,运用NMR、MS 等波谱技术共分离鉴定得到22 个化合物,分属于五环三萜类化合物、鞘糖脂类化合物等,其中有1 组6个新的鞘糖脂类化合物同系物,另外有7 个化合物首次从该植物中分离得到。 第二章报道蹄叶橐吾(Ligularia fischeri)根部乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR 等波谱解析,共分离鉴定得到18 个化合物,其中5 个是新化合物。它们的结构分别确定为3β-acetyl-6β, 8α, 10β-trihydroxyeremophila-7(11)-en-8, 12-olide (23), 3β-acetyl-8β,10β-dihydroxy-6β-(2-methylbutyryloxy)-eremophilenolide (24), 3β-acetyl-6β, 10β-dihydroxyeremophila-7(11), 8(9)-dien-8, 12-olide (25), 3β-acetyl-6β, 10β-dihydroxyeremophila- 7(11), 8(9)-dien-8, 12-olide (26), (3aR, 4R, 5S, 7aS)-2-acetyl-7ahydroxy-3a, 4, 5, 6, 7, 7a-hexahydro-1H-inden-5-yl acetate (27)。这5 个化合物经体外生物活性测试,结果表明化合物23 具有抑制酪氨酸磷酸酯酶的活性, 其IC50 值为1.30 μg/ml。 第三章概述了近二十年来艾里莫芬烷内酯类化合物的研究进展,包括其结构及药理活性两个方面,列举了从23 种植物中分到的114 个艾里莫芬烷内酯类化合物,同时也对其主要生物活性进行了总结。 This dissertation consists of three chapters. The first and second chapters elaborate the phytochemical investigation of Uncaria rhynchophylla and Ligularia fischeri. Thirty-seven compounds, including six new ones, were isolated and identified by spectroscopic methods and X-ray diffraction experiments. The third chapter is a review on the study progress of Eremophilanolides. The first chapter focus on the isolation and identification of chemical constituents from Uncaria rhynchophylla. Twenty-two compounds were isolated from the roots of U. rhynchophylla by repeat column chromatography over normal and reversed phase silica gel. Those compounds mainly belonged pentacyclic triterpenoids and sphingolipids. Among them, a series homologues of six sphingolipids were new compounds and seven compounds were firstly reported in this plant. The second chapter is about the phytochemical investigation of L. fischeri. Eighteen compounds were isolated and identified. Among them, four new erem-ophilanolides and a new dinoreremophilane derivative were characterized as 3β-acetyl-6β, 8α, 10β-trihydroxyeremophila-7(11)-en-8, 12-olide (23), 3β-acetyl-8β, 10β-dihydroxy-6β-(2-methylbutyryloxy)-eremophilenolide (24), 3β-acetyl-6β, 10β-dihydroxyeremophila-7(11), 8(9)-dien-8,12-olide (25), 3β-acetyl-6β, 10α-dihydroxyeremophila- 7(11), 8(9)-dien-8,12-olide (26), (3aR,4R,5S,7aS)-2-acetyl-7a-hydroxy-3a, 4, 5, 6,7, 7a-hexahydro-1H-inden-5-yl acetate (27) by spectroscopic analysis and confirmed by X-ray crystallography analysis. It was revealed that compound 23 has the ability to inhabit the PTP1B in vivo. And its IC50 is 1.30 μg/ml. The third part is a review on the study progress of Eremophilanolides.

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对157例胃肠道癌切除术后病人,随机分成术中腹腔温热灌洗化疗联合术后置泵持续动脉灌注及静脉微泵化疗组72例(简称治疗组)、单纯静脉化疗组85例(简称对照组),并对其腹腔转移率、肝转移率及3a生存率进行对照研究,取得了较满意的临床疗效。术中腹腔温热灌洗化疗联合术后置泵持续动脉灌注及静脉微泵化疗三途径综合治疗对胃肠道癌病人术后腹腔转移及肝转移有良好的防治作用。

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2001~2003年在长白山自然保护区内3个垂直植被带的典型群落红松阔叶林、云冷杉林和岳桦林内,利用网袋埋藏法对群落内的6个主要优势乔木树种凋落物进行埋藏分解试验,研究凋落物分解速率及其变化动态;同时利用分解模型,模拟预测凋落物的分解进展,为深入研究这6个树种的营养策略、群落养分循环等奠定基础,也为森林生态系统管理提供理论依据。研究结果表明,所研究的6个树种凋落物都表现出随时间进程失重率增大的现象,但失重率并不与时间呈线性相关。在分解的638d(1.75a)后,6种叶凋落物的分解速率明显升高。到分解实验结止时(699d),叶凋落物干重剩余率从小至大依次为白桦(24.56%)、紫椴(24.81%)、红松(38.48%)、鱼鳞云杉(41.15%)、岳桦(41.53%)和臭冷杉(42.62%)。枝凋落物分解速率明显低于叶,枝干重剩余率从小至大依次为紫椴(44.98%)、臭冷杉(64.62%)、红松(72.07%)、鱼鳞云杉(73.51%)、白桦(77.37%)和岳桦(80.35%)。在同一海拔高度,阔叶树种叶凋落物分解速率大于针叶树种。并且随着海拔的升高,叶凋落物分解速率逐渐减慢。模型分析预测结果表明,长白山北坡各垂直植被带的优势树种叶凋落物分解95%需4.5~8.0a;年分解系数为紫椴(0.686)>白桦(0.624)>红松(0.441)>鱼鳞云杉(0.406)>臭冷杉(0.397)>岳桦(0.385);枝凋落物分解95%需7.8~29.3a,不同树种间的差异明显。枝年分解系数为紫椴(0.391)>臭冷杉(0.204)>红松(0.176)>鱼鳞云杉(0.157)>白桦(0.148)>岳桦(0.102)。

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固氮细菌是土壤生态系统中十分重要的功能群之一,在土壤氮素循环中发挥着不可替代的作用。本文通过传统培养方法和固氮基因(nifH)PCR-DGGE指纹图谱分析方法,从微生物功能群角度,研究了长期有机污水灌溉对土壤表层和亚表层固氮细菌种群数量和多样性的影响。结果表明,土壤表层固氮细菌数量随土壤污染的增高而不同程度减少,亚表层自生固氮菌数量无明显变化。从DGGE指纹图谱结果来看,对照清洁土壤的固氮细菌种群多样性较丰富,其Shannon指数在表层为2.4674,在亚表层为2.8210,分别高于受有机污水灌溉不同年限的土壤固氮细菌种群shannon指数,且种群的相似程度有所差异,说明种群结构发生了一定的变化。改清灌3a和改清灌30a土壤固氮细菌种群shannon指数分别略有增加,但种群结构并没有得到完全恢复。污水灌溉对土壤固氮细菌种群的影响具有长期的生态效应,是导致土壤生态与结构功能改变的重要因素之一。

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Some novel ferrocenylphosphine-amidine ligands with central and planar chirality were prepared from (R,S-p)-PPFNH2-R 3 and its diastereomer (S,S-p)-PPFNH2 3a. The efficiency and diastereomeric impact of these ferrocenylphosphine-amidine ligands in the palladium-catalyzed asymmetric allylic substitution was examined, and up to 96% e.e. with 98% yield was achieved by the use of ligand (R,S-p)-4a with a methyl group in the amidino moiety. The results also indicated that (R)-central chirality and (S-p)-planar chirality in these ferrocenylphosphine-amidine ligands were matched for the palladium-catalyzed asymmetric allylic alkylation. (C) 2003 Elsevier Ltd. All rights reserved.

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应用生态足迹分析方法研究了翁牛特旗地区 2 0a的生态足迹变化 ,并以 1984 ,1993,2 0 0 2年的生态足迹为例进行分析 ,这 3a的人均生态足迹分别为 :0 .4 4 98hm2 /人 ,0 .4 75 8hm2 /人 ,0 .6 6 6 2hm2 /人。结果表明 ,该地区人均生态足迹处于增加趋势 ,与人均生态承载力相比 ,一直处于生态盈余状态。人均生态足迹与人均GDP、人均消费均表现为指数关系 ,拟合系数分别为 0 .94 38和 0 .9398。这说明就本尺度而言 ,翁牛特旗的生态足迹需求对本地区生态系统的可持续发展暂时还未构成威胁。

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坡地土壤降雨入渗、径流和侵蚀过程与土壤结构密切相关。试验样地为宁夏固原云雾山自然保护区的坡耕地、退耕6a、退耕11a(前8a放牧,后3a禁牧)和退耕16a坡地,室内测定土壤结构指标,野外采用基于径流-入流-产流方法的新型降雨仪器在17、43和56mm/h雨强下观测坡地土壤的入渗性能,分析土壤结构特征对入渗的影响。对土壤结构的稳定性指标、孔隙性指标和分形维数指标进行分析,结果表明,随着退耕年限的延长,土壤团聚体稳定性增强,土壤结构孔隙状况得到明显改善。模拟降雨结果显示,随着雨强的增大,退耕地的土壤入渗率增加,但坡耕地反而降低。退耕11a样地受放牧牲畜践踏影响,入渗性能最差。通过逐步回归分析可知,在17mm/h和56mm/h雨强下,影响土壤稳定入渗率的土壤结构因子主要是容重和有机碳含量,而在43mm/h雨强下主要是毛管孔隙度和非毛管孔隙度。土壤有机碳含量和孔隙状况的差异致使土壤结构特征不同,从而对入渗性能和过程产生明显的影响。

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可持续发展的定量测度研究是当前国际上关于生态经济研究的前沿问题之一。生态足迹分析法是近年来发展的用于定量研究和判断一个国家或地区的可持续发展状况的新方法。应用生态足迹的方法 ,以辽宁省 2 0 0 0年 ,2 0 0 1年 ,2 0 0 2年统计资料为依据 ,对其 1999~ 2 0 0 1年 3a的生态足迹进行了实证计算和研究 ,从纵向比较并分析了辽宁省生态足迹的变化规律及其原因。研究结果表明 :辽宁省生态赤字呈逐年增加的趋势 ,1999年人均生态赤字为 2 .2 90 hm2 ,2 0 0 0年为 2 .36 8hm2 ,2 0 0 1年为 2 .4 74hm2 ,其主要影响因素是由于资源过度消耗 ,人口增长以及耕地减少等。通过生态足迹的研究 ,提出了辽宁省在振兴东北老工业基地 ,进行可持续发展过程中应采取的对策措施

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Hydrogenolysis of mono(cyclopentadienyl)-ligated rare-earth-metal bis(alkyl) complexes Cp'Ln-(CH2SiMe3)2(THF) (Ln = Y (1a), Dy (1b), Lu (1c); Cp' = C5Me4SiMe3) with PhSiH3 afforded the mixed hydride/alkyl complexes [Cp'Ln(mu-H)(CH2SiMe3)(THF)](2) (Ln = Y (2a), Dy (2b), Lu (2c)). The overall structure of complexes 2a-c is a C-2-symmetric dimer containing a planar symmetric Ln(2)H(2) core at the center of the molecule. Deprotonation of ArOH (Ar = C6H2-Bu-t(2)-2,6-Me-4) by the metal alkyl group of 2a-c led to formation of the mixed hydride/aryloxide derivatives [Cp'Ln(mu-H)(OAr)](2) (Ln = Y (3a), Dy (3b), Lu (3c)), which adopt the dimeric structure through hydride bridges with trans-accommodated terminal aryloxide groups.

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This paper describes the synthesis and selected reactions of a series of crystalline mono(beta-diiminato) yttrium chlorides 3a, 3b, 4a, 4b, 5a, 5b, 5c and 9. The X-ray structure of each has been determined, as well as of [YCl(L-4)(2)] (6), [Y(L-1)(2)OBut] (7) and [Y{CH(SiMe3)(2)}(thf)(mu-Cl)(2)Li(OEt2)(2)(mu-Cl)](2) (8).

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A series of new rare-earth metal bis(alkyl) complexes [L(1-3)Ln(CH2SiMe3)(2)(THF)(n)] (L-1 = MeC4H2SCH2NC6H4(Ph)(2)P=NC6H2Me3-2,4,6: Ln = Sc, n = 1 (1a); Ln = Lu, n = 1 (1b); L-2 = MeC4H2SCH2NC6H4(Ph)(2)P=NC6H3Et2-2,6: Ln = Sc, n = 1 (2a); Ln = Lu, n = 1 (2b); Ln = Y, n = 1 (2c); L-3 = MeC4H2SCH2NC6H4(Ph)(2)P=(NC6H3Pr2)-Pr-i-2,6: Ln = Sc, n = 0 (3a)) and (LSc)-Sc-4(CH2SiMe3)(2()THF) (4a) (L-4 = C6H5CH2NC6H4(Ph)(2)P=NC6H3Et2-2,6) have been prepared by reaction of rare-earth metal tris(alkyl)s with the corresponding HL1-4 ligands via alkane elimination.

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Reaction of 7-{(N-2,6-R)iminomethyl)}lindole (HL1, R = dimethylphenyl; HL2, R = diisopropylphenyl) and rare-earth metal tris(alkyl)s, Ln(CH2SiMe3)(3)(THF)(2), generated new rare-earth metal bis(alkyl) complexes LLn(CH2SiMe3)(2)(THF) [L = L-1: Ln = Lu. (1a), Sc (1b); L = L-2 : Ln = Lu (3a), Se (3b)] and mono(alkyl) complexes L-2 Lu-2(CH2SiMe3) (4a). Treatment of alkyl complexes 1a and 4a with N,N'-diisopropylcarbodiimide afforded the corresponding amidinates (LLu)-Lu-1{iPr(2)NC(CH2SiMe3) NiPr2}(2) (2a) and L-2 Lu-2{iPr(2)NC(CH2SiMe3)NiPr2} (5a), respectively.

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Newrareearth metal bis(alkyl) complexes [(NPNPh)Ln(CH2SiMe3)(2)(THF) (NPNPh:N(Ph)PPh2=NC6H2Me3-2,4,6; Ln = Sc (3a), Ln = Y (3b), Ln = Lu (3c)) and [(NPNPy)Sc(CH2SiMe3)(2)(THF)1 (NPNPY = N(Py)PPh2=NC6H2Me3-2,4,6) (3d)) have been prepared via protonolysis reaction between rare earth metal tris(alkyl)s and the corresponding iminophosphonamines. Complexes 3a-d are analogous monomers of THF solvate. Each metal ion coordinates to a eta(2)-chelated NPN ligand and two cis-located alkyl groups, adopting tetrahedron geometry.

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A series of salicylaldimine-based neutral Ni(II) complexes (3a-j) [ArN = CH(C6H40)]Ni(PPh3)Ph [3a,Ar = C6H5; 3b,Ar = C6H4F(o); 3c, Ar = C6H4F(m); 3d, Ar = C6H4F(p); 3e, Ar = C6H3F2(2,4); 3f, Ar = C6H3F2(2,5); 3g, Ar = C6H3F2(2,6); 3h, Ar = C6H3F2(3,5); 3i, Ar = C6H2F3(3,4,5); 3j, Ar = C6H5] have been synthesized in good yield, and the structures of complexes 3a and 3i have been confirmed by X-ray crystallographic analysis. Using modified methylaluminoxane as a cocatalyst, these neutral Ni(II) complexes exhibited high catalytic activities for the vinylic polymerization of norbornene.

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A series of (alpha-diimine)nickel(II) complexes [ArN = C(Nap)C = NAr]NiBr2 (Nap = 1,8-naphthdiyl, Ar = 2,6-Me2C6H3, 3a; Ar = 2,4,6-Me3C6H2 3b; Ar = 2,6-Me-2-4-tBuC(6)H(2), 3c; Ar 2,6-Me-2-4-BrC6H2, 3d; Ar = 2,6-Me-2-4-ClC6H2, 3e; Ar 2,6-iPr(2)C(6)H(3), 3f; Ar = 2,4,6-iPr(3)C(6)H(2), 3g; Ar = 2,6-iPr-4-BrC6H2, 3h) have been synthesized, characterized, and investigated as precatalysts for ethylene polymerization in the presence of modified methylaluminoxane (MMAO).