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A New Approach Towards (\pm)-4-Ipomeanol and Its 2-Furyl Regioisomer
(\pm)-4-ipomeanol solvolysis antimicrobial activity
2010/4/19
The cytotoxic furan derivative (\pm)-4-ipomeanol (1) and its regioisomer (8) were prepared in a new and efficient way starting from commercially available furan derivatives. In both cases the key step...
氨基酸广义疏水标度(GH-scale)用于HLA-A*0201限制性CTL表位的定量预测研究
氨基酸广义疏水标度 HLA-A*0201 CTL表位 定量构效关系 遗传-偏最小二乘回归
2013/10/21
天然氨基酸149个疏水性质经主成分分析得到了一种新氨基酸描述子——氨基酸广义疏水标度(GH-scale). 用GH-scale结合遗传偏最小二乘(GPLS)算法对152个HLA-A*0201限制性CTL表位进行定量构效关系(QSAR)研究. 所建模型拟合及交叉检验复相关系数分别为<=0.813sPA CLASS="formnla">和Q2 = 0.725. 研究表明, 疏水作用在CTL表位与HLA...
超支化高分子多分散指数是3/2还是5/2?
超支化高分子 多分散指数 多分散指标
2013/10/21
研究了超支化高分子聚合反应过程总分子数的变化, 给出接近反应终点时n-聚物浓度的渐近表达式, 得到的多分散指数(polydispersity exponent)与经典结果一致. 进一步给出数均、重均和z-均聚合度的渐近表达式, 并得到反应接近终点时, 多分散指标(polydispersity index)趋近于1的合理结果.
Organotin(IV) Derivatives of N-Maleoylamino Acids: Their Synthesis and Structural Elucidation
Organotin(IV) complexes N-Maleoylamino acids FT-IR Multinuclear NMR Mö ssbauer spectroscopy Mass spectrometry
2010/4/19
Organotin carboxylates of general formula R3SnL (1), (2), (4) and (6), R2SnL2 (5) and {[(R2SnL)2O]2} (3), where L = N-maleoylglycinate, N-maleoyl-b-alaninate and N-maleoylmethioninate, were prepared. ...
超低本底化学流程和单颗粒云母Rb-Sr等时线定年
超低化学流程本底 单颗粒 云母Rb-Sr定年 金伯利岩
2013/10/17
低化学流程本底和高精度同位素测定是实现微量样品处理的必要条件. 以辽宁复县金伯利岩中金云母单颗粒Rb-Sr等时线定年为实例, 介绍处理微量样品的超低本底化学流程, 以及应用新型高精度热电离质谱计(IsoProbe-T)精确测定小于ng级Sr同位素组成的方法. 单颗粒矿物Rb-Sr同位素分析技术可以应用于高分辨同位素示踪和年代学研究, 从而进一步拓展Rb-Sr同位素体系的研究应用空间.
Na(HB(pz)3)和Na(HB(3, 5-Me2pz) 3)分别与VOSO4·nH2O和KSCN及对应的吡唑在甲醇体系中反应, 得到两个新型钒氧配合物VO(HB(pz) 3)(pz)(SCN)(1)和VO(HB(3,5-Me2pz) 3)(3,5-Me2pz)(SCN)-(SCNH) 2(2). 通过元素分析、红外光谱和紫外光谱对配合物进行了表征, 并且研究了它们的荧光光谱, 结果表明配合物的...
Synthesis and Isolation of New Regioisomeric 4-Thiazolidinones and Their Anticonvulsant Activity
4-thiazolidinones synthesis separation anticonvulsant activity
2010/4/20
Two regioisomer series, 2-(3-ethyl-4(3H)-quinazolinone-2- ylmercaptoacetylhydrazono)-3-alkyl/3-aryl-5-methyl-4-thiazolidinones (12-21) and 2-arylimino-3-(3-ethyl-4(3H)-quinazolinone-2-ylmercaptoacetyl...
酶催化聚合与原子转移自由基聚合相结合的方法合成三嵌段共聚物
Novozyme-435 原子转移自由基聚合 酶促缩聚 嵌段共聚物
2013/10/17
固定化酶Novozyme-435催化1, 10-癸二酸/1, 10-癸二醇酶促缩聚得到端基都是羟基的聚酯(PSD), 用a-溴代丙酰溴将聚酯的端羟基官能化形成双官能度引发剂, 在CuCl/bpy体系中, 与苯乙烯进行原子转移自由基聚合反应(ATRP)得到三嵌段共聚物: 聚(苯乙烯)-聚(1,10-癸二酸/1,10-癸二醇酯)-聚(苯乙烯)(PSt-b-PSD-b-PSt), 通过核磁共振(NMR)...
Synthesis of Some Novel Optically Active Isocoumarin and 3,4-Dihydroisocoumarin Containing L-valine and L-leucine Moieties
Isocoumarin Dihydroisocoumarin Homophthalic Amino acid
2010/4/20
Phthalic anhydride was reacted with L-Valine and L-Leucine in a mixture of acetic acid and pyridine at room temperature, and then was refluxed at 90-100 °C and N-phthaloyl-L-valine or N-phthaloyl-L-le...
转铁蛋白及其抗体分子间作用的原子力显微镜探测
饱和铁转铁蛋白 脱铁转铁蛋白 转铁蛋白抗体 原子力显微镜
2013/10/16
采用原子力显微镜对饱和铁转铁蛋白和脱铁转铁蛋白与转铁蛋白抗体之间的相互作用进行研究. 对转铁蛋白抗体层层自组装在喷金基片表面并且与抗原蛋白之间特异性结合的形貌进行了表征. 通过原子力显微镜对分子间力的曲线的探测, 比较了饱和铁转铁蛋白和脱铁转铁蛋白与抗体之间的作用力的差异. 实验表明, 饱和铁转铁蛋白与抗体分子之间结构互相嵌合, 结合更加紧密; 分子间力的曲线亦显示饱和铁转铁蛋白与抗体之间的特异性...
Methoxyflavonoids from Pinaropappus roseus
Pinaropappus roseus Asteraceae rhamnazin 3-O-rutinoside rhamnocitrin 3-O- rutinoside isorhamnetin 3-O-rutinoside flavonoids
2010/4/20
Three rare methoxyflavonoids, rhamnazin 3-O-rutinoside (1), rhamnocitrin 3-O-rutinoside (2) and isorhamnetin 3-O-rutinoside (3), were isolated from the methanolic extract of Pinaropappus roseus toget...
Atomic Absorption and Spectrophotometeric Determinations of Salicylhydroxamic Acid in Its Pure and Pharmaceutical Dosage Forms
Atomic absorption spectrometry (AAS) spectrophotometry SHAM salicylhydroxamic acid drug analysis Cu complexes
2010/4/21
A new method for the indirect determination of salicylhydroxamic acid (SHAM) using atomic absorption spectrometry (AAS) was proposed. The method is based on precipitating the ion associate complex of ...
化学学科发展战略研讨会召开
化学学科发展战略研讨会 召开
2013/7/10
研讨会由中国科学院化学部和国家自然科学基金委员会化学科学部共同组织，2003年2月15—16日在上海召开。主要围绕化学学科发展趋势及新学科生长点、突破点开展研讨，以完成“学科发展战略研究”总体组安排的咨询任务。
The Selective Protection and Deprotection of Ambident Nucleophiles with Parent and Substituted Triarylmethyls
Aminophenols triphenylmethyl chloride 4 4'-dimethoxytriphenylmethyl chloride and selective protection
2010/4/22
N-triphenylmethyl and N-4,4'-dimethoxytriphenylmethyl of o-aminophenol, m-aminophenol, and p-aminophenol compounds were easily prepared from triphenylmethyl chloride and 4,4'-dimethoxytriphenyl- methy...