中国松辽盆地白垩系磁性地层

本文根据对松辽盆地白垩系24个钻井岩芯和泉头剖面,共2235块古地磁标本及样品测试结果,总结了松辽平原白垩系各岩组的极性特点,发现了存在于营城组、登娄库组、姚家组、嫩江组的反极性带,论证了这些反极性带的存在及其时代归属,编制了各钻井及白垩系综合极性柱,讨论了松辽盆地白垩系的划分与对比。     

反相HPLC中溶剂极性对容量因子的影响

考查了反相HPLC中,溶剂极性改变对容量因子的影响及其相关规律。结果发现:其影响是复杂的,不同溶质对不同溶剂极性改变的敏感程度差异较大。反映在容量因子的变化上就是:有时极性改变较大,但某些溶质的容量因子变化却较小;反之有时极性改变较小,但某些溶质的容量因子变化却较大。随着溶剂极性的改变,原来容量因子小的溶质变化幅度小,原来容量因子大的溶质变化幅度大。最后探讨了产生这种复杂变化的机理。     

基于香豆素荧光团的新型极性检测荧光探针的开发及其成像应用

极性是生物微环境的重要参数之一, 在很大程度上, 生物体内许多生命活动都受到极性变化的影响, 本工作通过改变香豆素母体上的推-拉电子基团, 设计并合成了一种具有较大斯托克斯位移的新型极性荧光探针COM-PO, 该探针的荧光强度和波长会随着测试体系的极性变化而发生改变. 当极性增加时, COM-PO的激发态能量会通过偶极-偶极的相互作用散失在溶剂中, 荧光发射强度降低, 而在低极性溶剂中荧光发射强度增强, 利用这种特性实现了对极性的检测. 本工作通过荧光光谱、荧光成像实验表明COM-PO能够在样品中实现极性检测, 该探针有望实现与极性相关的疾病的早期诊断.     

基于离子液体极性下苯二溴代反应选择性研究

以溴苯为原料与液溴反应,通过在极性溶剂中添加离子液体改变溶剂的极性、改变反应温度等条件,提高其邻位或对位的单一选择性。结果表明,溶剂极性增大,对位产物选择性提高,溶剂极性降低,邻位产物选择性提高。当CH2Cl2中离子液体含量为2(wt)%时,对位产物相对含量达到最大(92.02%)。     

含离子液体的极性溶剂中溴苯的二溴代反应选择性

以溴苯为原料与液溴反应,通过在极性溶剂中添加离子液体改变溶剂的极性、改变反应温度等条件,提高其邻位或对位的单一选择性。结果表明,溶剂极性增大,对位产物选择性提高,溶剂极性降低,邻位产物选择性提高。当CH2Cl2中离子液体含量为2(wt)%时,对位产物相对含量达到最大(92.02%)。     

银纳米粒子表面油酸盐吸附的分子模拟

采用分子力学方法模拟了油酸盐分子在银纳米粒子(111)表面的两种主要吸附形态: 双键吸附和羧基吸附, 计算了不同溶剂环境中油酸盐分子的吸附能和振动频率. 结果表明: 作为银纳米粒子保护剂的油酸盐能够稳定地存在于极性和非极性溶剂环境中, 与银表面的作用方式随溶剂极性的改变而改变, 水相中以双键吸附为主, 而在有机相中主要是羧基吸附. 这与红外光谱实验的推论基本吻合. 从而在分子水平上为实验结果提供了有价值的理论支持和微观信息.     

气液色谱法测量芳烃在芳烃衍生物中的活度系数

用气液色谱法测量了C_6～C_8芳烃在芳烃衍生物中的无限稀活度系数。以Hildebrand-Scatchard-Flory-Huggins公式进行处理,得到了非极性或微极性溶剂的溶解度参数δ,以修正的Hildebrand-Scatchard-Flory-Huggins公式进行处理,得到了芳烃溶质与各极性溶剂相互作用常数ι_(12)。     

关于分子极性的演示实验

分子的极性和非极性可以通过下述现象演示出来。Dennis Garvise等人指出:带电的棒能使垂直向下流动的细水流的流动方向发生改变。而四氯化碳是非极性分子,和具有极性的水分子不同,它的细液流的流动方向却不受电场的影响。     

几种极性有机晶体的生长习性与形成机理 2: 分子堆积、界面结构与晶体的习性

极性有机晶体在不同的溶剂中具有明显不同的生长习性, 主要有两个方面的原因: 一是极性有机晶体属非中心对称性晶类, 晶体具有极轴, 极轴的存在对分子堆积和晶体生长具有重要影响; 另一是极性有机晶体的界面结构不同, 溶剂与晶体界面的相互作用不同, 使得晶体同一面族的生长速率不同, 从而导致了晶体习性的改变。本文从几种典型极性有机晶体的分子排列和结构特征出发, 着重探讨了极性有机晶体的界面结构的差异对晶体习性的影响; 结合晶体生长界面与溶剂分子的相互作用进一步理解了晶体生长的溶剂效应; 通过理解极性有机晶体的习性机制, 探讨了晶体实际形态的控制。     

几种极性有机晶体的生长习性与形成机理Ⅱ.分子堆积、界面结构与晶体的习性

极性有机晶体在不同的溶剂中具有明显不同的生长习性,主要有两个方面的原因:一是极性有机晶体属非中心对称性晶类,晶体具有极轴,极轴的存在对分子堆积和晶体生长具有重要影响;另一是极性有机晶体的界面结构不同,溶剂与晶体界面的相互作用不同,使得晶体同一面族的生长速率不同,从而导致了晶体习性的改变.本文从几种典型极性有机晶体的分子排列和结构特征出发,着重探讨了极性有机晶体的界面结构的差异对晶体习性的影响;结合晶体生长界面与溶剂分子的相互作用进一步理解了晶体生长的溶剂效应;通过理解极性有机晶体的习性机制,探讨了晶体实际形态的控制.     

A novel route to 5-substituted 3-isoxazolols. Cyclization of N, O-DiBoc beta-keto hydroxamic acids synthesized via acyl Meldrum's acids

3-Isoxazolols are most often synthesized from a beta-keto ester and hydroxylamine. This cyclization typically gives rise to a major byproduct, the corresponding 5-isoxazolone. We have found that N, O-diBoc-protected beta-keto hydroxamic acids can be synthesized and cyclized to 5-substituted 3-isoxazolols without formation of any byproduct. We present a novel and versatile three-step procedure in which carboxylic acid derivatives are converted into acyl Meldrum's acids which, upon aminolysis with N, O-bis(tert-butoxycarbonyl)hydroxylamine, lead to the N, O-diBoc-protected beta-keto hydroxamic acids. These hydroxamic acid analogues were then, upon treatment with hydrochloric acid, cyclized to the corresponding 5-substituted 3-isoxazolols.     

Optically active polyamidoimides based on amino acids containing cyclohexane fragment

New amino carboxylic acids containing a cyclohexane fragment and an L-leucine or L-valine fragment were synthesized. The reactions of the synthesized amino acids with 4,4′-oxydiphthalic anhydride gave in quantitative yields the dicarboxylic acids, which were converted to the corresponding dichlorides. Low-temperature polycondensation of the synthesized dichlorides with 4,4′-diaminodiphenyl ether yielded optically active polyamidoimides, which are soluble in various organic solvents and exhibit enhanced heat resistance. The structures of the synthesized monomeric compounds and polymers were confirmed by elemental analysis, IR and ¹H NMR spectroscopy, and high-resolution mass spectrometry. Specific rotation angles of the synthesized amino carboxylic acids and polyamidoimides were determined.     

Synthesis of novel chiral bisazetidines by the hydroalane reduction of bis-beta-lactams

A series of novel chiral bisazetidines in which two azetidine rings are either directly connected or coupled in tandem style, are synthesized in good yields by the hydroalane reduction of the corresponding bis-beta-lactame.     

Synthesis and Infrared Absorption Spectra of α-methyl-2′-hydroxy-chalcones: I. α-methyl-2′-hydroxychalcone and its 4-Substituted Derivatives

Six 2′-hydroxychalcone derivatives with a methyl group on the α-position were synthesized. Infrared absorption spectra of these new compounds are discussed taking their corresponding α-hydrogen chalcoes which were also synthesized for comparison. This latter study is also utilized as a proof for the structures of these compounds of a new series.     

Practical synthesis of 2'-deoxy-4'-thioribonucleosides: substrates for the synthesis of 4'-thioDNA

We report herein a practical synthesis of 4'-thiothymidine (15) and appropriately protected 2'-deoxy-4'-thiocytidine (16), -thioadenosine (27), and -thioguanosine (29) derivatives, substrates for the synthesis of 4'-thioDNA, from the corresponding 4'-thioribonucleosides. 2'-deoxy-4'-thiopyrimidine nucleosides were synthesized using a radical reaction of the corresponding 2'-alpha-bromo derivatives, which were prepared via 2,2'-O-anhydro derivatives. 2'-deoxy-4'-thiopurine nucleosides were synthesized using the same radical reaction of the corresponding 2'-beta-bromo derivatives.     

Synthesis of some thioxoimidazole structures of the quinoline andindole series

Some 2-thioxoimidazotetrahydroquinolines and 2-thioxoimidazoindolines have been synthesized by the cyclization with carbon disulfide of the corresponding o-diamines, which were obtained by the reduction of the o-dinitro derivatives with hydrazine hydrate in the presence of Raney nickel.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1112–1114, August, 1973.The compounds synthesized are given in Table 1.     

Polymethylene dyes derived from heterocyclic bases containing condensed thiophene rings

Some new polymethine dyes of the cyanine and merocyanine series which are derivatives of 5- and 6- thienopyridines are synthesized. Replacement of a vinyl group at a sulfur atom in the condensed benzene ring of quinoline in dyes which are derivatives of this base, always leads to a bathochromic shift of the absorption maximum of the corresponding dyes.     

Oxygen-atom transfer reagents: New,reactive α-azohydroperoxides

3,4,4-Trimethyl-4,5-dihydro-5-hydroperoxy-3,5-diaryl-3H-pyrazoles, synthesized by autoxidation of the corresponding 3,4-dihydro-2H-pyrazoles, are a new type of cyclic α-azohydroperoxide which is of high reactivity in oxygen-atom transfer chemistry.     

2-Quinazolylguanidines in Heterocyclization Reactions. 2. Condensation with α,β-Unsaturated Carbonyl Compounds

4,6,6-Trimethyl-1,4-dihydropyrimidines have been synthesized by condensation of 2-quinazolylguanidines with mesityl oxide. The analogous reaction with benzalacetone leads to unstable 4-methyl-6-phenyl-1,4-dihydropyrimidines, which are oxidized to the corresponding 4-methyl-6-phenylpyrimidines.     

Synthesis of Novel 1-(substituted phenyl)-2-phospholene 1-Oxide Derivatives

Several novel 1-(substituted phenyl)-2-phospholene 1-oxide derivatives, which are analogs of sugars having a phosphorus atom in place of the ring oxygen of normal sugars, were synthesized from the corresponding 2-phospholenes as the starting materials. Structures of all the synthesized compounds were unequivocally confirmed by IR, 1 H, 13 C, and 31 P NMR spectral, elemental, and X-ray crystallographic analyses.