可配位液晶分子的合成及表征

以焦性没食子酸和异烟酸为原料合成了带吡啶官能团的液晶配体。将液晶和配体相结合,成功合成了具有配位能力的液晶分子,采用红外光谱（FT-IR）对其结构进行了表征,通过示差扫描量热法（DSC）,热失重（TGA）和偏光显微镜（POM）等方法研究了它的液晶性和相变温度。结果表明,合成产物液晶性良好。     

酰胺型冠醚液晶的合成及性质研究

冠醚液晶出现至今仅十几年，由于其具有冠醚和液晶的各种性质而受到人们的关注［‘－‘1．我们在已有工作的基础上，设计合成了5种酸胺型冠醚液晶分子（4—8），其中3种分子（4－6）具有液晶性．合成路线如下：1结果与讨论合成样品4－8经IR、MS、‘HNMR和元素分析确证其结构．用DSC和Texture图测定了4－6的液晶性质，其结果见图1．化合物7、8无液晶性，分子长径比分别为5．8：I，满足一般律状向列液晶分子长径比的要求．当在其分子链中增加1个苯环（5、6）时，分子的刚性链比例增大，整个分子的刚性增加，则具有液晶性．双臂型冠醚液…     

新型含双键的胆固醇单体及其液晶聚合物的合成

胆固醇分别与丁二酸酐、邻苯二甲酸酐反应制得带羧基功能基团的胆固醇单酯———丁二酸单胆固醇酯(3a),邻苯二甲酸单胆固醇酯(3b);3与甲基丙烯酸羟乙酯在DCC/DMAP催化下完成酯化反应合成了新型含双键的胆固醇单体(4a和4b);4经抽真空-冷冻-通氮气循环三次后真空封管聚合制得液晶聚合物(5a和5b),其结构经1H NMR,IR表征;5的热性能及液晶形态用DSC,TGA和POM研究。     

过渡金属催化交叉偶联反应及其在液晶合成中的应用

过渡金属催化交叉偶联反应及其在液晶合成中的应用杜卫红安忠维徐茂梁（西安近代化学研究所西安７１００６１）关键词过渡金属催化交叉偶联反应合成液晶液晶是一类具有特殊物理性能的有机化合物，其分子结构要求长径比大于４，官能团包括芳（杂）环、脂环、烷基、双键、叁...     

低相变温度锌卟啉液晶的合成与表征

卟啉液晶作为一种功能型盘状液晶,已经受到了科学家们的高度重视^[1]。自1980年Goodby^[2]首次合成出简单的卟啉液晶以来;各国学者对卟啉液晶的合成做了相应的研究工作,但其液晶相变温度偏高^[3,4],相区宽度偏窄^[3]。本文首次合成出相变温度较低,相区宽,含有8,10,12和14碳的酰氧基的四种卟啉液晶5、10、15、20－四（对－酰氧基）苯基卟啉液晶5、10、15、20－四（对－酰氧基）苯基卟啉锌（Ⅱ）配合物[分别简称为TOPPZn,TDPPZn,TLPPZn,TMPPZn]。研究4种配合物的液晶行为,其液晶相相变温度最低始于－36．4℃,相区宽达175℃,是一种具有应用前景的卟啉液晶。     

TN液晶稀释剂4－（4＇－正丙基环己基）苯甲（乙）醚的合成

ＴＮ液晶稀释剂４－（４＇－正丙基环己基）苯甲（乙）醚的合成马汝建，程旻，荣国斌（华东理工大学化学系上海２００２３７）关键词　ＴＮ液晶，稀释剂，合成扭曲向列（ＴＮ）型液晶材料的粘度越低，响应速度越快［１］．为降低液晶材料的粘度，改善其性能，常在ＴＮ液晶...     

星形聚乳酸

星形聚乳酸以其独特的结构与性能引起了人们的广泛兴趣,通常使用“先核后臂”法进行合成。本文根据不同类型的“核”进行分类,如小分子多羟基醇（天然糖醇）、无机（杂环）化合物的衍生物、金属有机化合物、多元酚的衍生物和星形高分子等,综述了星形聚乳酸近年来合成（尤其是丙交酯开环聚合法合成）、性能与应用等方面的研究进展,指出星形聚乳酸高分子量、低黏度、良好溶解性和热稳定性等优点有利于其在药物缓释等生物医用材料中的加工应用。     

β—二酮合钴（Ⅱ）,镍（Ⅱ）,铜（Ⅱ）棒状金属有机液晶

合成了β－二酮合钴（Ⅱ）、镍（Ⅱ）、铜（Ⅱ） 棒状金属有机液晶，并对其介晶性进行了表征。研究表明，所有目标配合物都具有液晶性，其中，配合物３，６在熔点附近产生分解现象。     

奥贝胆酸关键中间体杂质的设计与合成

以易得的中间体5为原料,合成了5个奥贝胆酸关键中间体杂质,分别为6-β-乙基-7-酮石胆酸（A）、 6-β-乙基-7-酮-石胆酸甲酯（B）、 3-α-乙酰基-6-β-乙基-7-酮石胆酸（C）、 6-α-乙基-7-酮-石胆酸甲酯（D）、 3-α-乙酰基-6-α-乙基-7-酮-石胆酸（E）,其结构经¹HNMR、 ¹³CNMR和HR-MS确证。并通过单晶确 定了杂质A的构型,进一步确认了化合物的结构。      

星型液晶的合成、相行为与应用研究

通过SiCl4的Si-Cl键与偶氮苯类液晶基元末端OH的有效联接，合成了三种新的 星型液晶，利用红外光谱（IR）、核磁共振（^1H NMR)对其分子结构进行了鉴定， 利用偏光显微镜（POM）和示差扫描量热法（DSC）对 其液晶相行为进行了表征， 并对其在毛细管气相色谱分析中的应用进行了初步探讨。     

Gas-liquid chromatographic determination of fatty acid composition of cholesteryl esters in human serum using silica Sep-Pak cartridges

A simple and fast analytical procedure for separation and purification of cholesteryl esters of human serum is described. A single lipid extract, together with spiked cholesteryl pentadecanoate, as an internal standard, was passed through a Silica Sep-Pak cartridge. 1.5% diethyl ester in light petroleum was used to elute cholesteryl esters from the column. The separation was verified with thin-layer chromatography on silica gel using light petroleum-diethyl ether-glacial acetic acid (80:20:1) as a solvent. A very clean thin-layer chromatogram of cholesteryl esters without any additional spots of other lipids was obtained. The cholesteryl esters were quantitated by analyzing their fatty acid composition as methyl esters by gas-liquid chromatography. The coefficients of variation were 0.8--4.9% for the major fatty acids (C16:0, C16:1, C18:1, C18:2, C20:4) and 6.7--30.8% for the minor fatty acids (C18:0 and C20:0). The recoveries for cholesteryl palmitate, cholesteryl oleate and cholesteryl linoleate were 90.7, 92.3 and 91.0%, respectively.     

Design and Synthesis of Novel Molecular Tweezers Derived from Chenodeoxycholic Acid

A novel type of chiral molecular tweezers has been designed and synthesized by usingchenodeoxy cholic acid as spacer and the aromatic compounds as arm. Their structures werecharacterized by 1HNMR, IR, MS spectra and elemental analysis. These chiral molecular tweezersshowed good enantioselectivity for D-amino acid methyl esters.     

Enzymes in polymer chemistry, 9. Polymerizable oligoesters from cholic acid via lipase catalyzed condensation reactions

Regioselective oligocondensation of cholic acid in the 3-position was achieved in organic solution in the presence of a lipase from Candida antarctica. Furthermore, a mixture of cholic acid, 11-methacryloylaminoundecanoic acid and the lipase resulted in the production of a radically polymerizable oligo(cholic acid ester) bearing exactly one methacrylic end group. This new monomer was polymerized radically yielding the corresponding comb-polymers bearing several cholic acid esters at the end of the side chains.     

Fine Structure of Hydrogen Bonds in Cholic Acid Revealed by 2DIR Spectroscopy

Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.     

含胆酸高分子化合物的制备和特性*

胆酸是哺乳动物体内合成的一种天然化合物,具有特殊的分子结构和优良的生物适应性。由胆酸合成的高分子化合物保持了胆酸的部分性质,如双亲性、手性、侧基反应活性和自组装性能等。在化学和药学领域,含胆酸高分子材料具有重要的应用价值。本文从自由基聚合形成的含胆酸高分子化合物、胆酸修饰的高分子化合物和胆酸聚合物等几个方面综述了含胆酸高分子化合物的制备和特性,并对胆酸在高分子材料方面的新用途作了展望。     

Fine Structure of Hydrogen Bond in Cholic Acid Revealed by 2DIR Spectroscopy

Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.     

Synthesis of new bio‐based hydrogels derived from bile acids by free‐radical photo‐polymerization

In this article, the study on the swelling and thermal behaviors of a new series of bile acid‐based polymeric hydrogels is reported. For this purpose, in the first step, the reduction of carboxyl acid groups of some common bile acids including cholic acid (CA), chenodeoxy cholic acid (CDCA), and lithocholic acid (LCA) to the corresponding alcohols by lithium aluminum hydride (LiAlH₄) in THF solution is performed. Then, hydroxyl functionalities of the obtained products are reacted with the acryloyl chloride in the presence of triethylamine (TEA). Finally, the cross‐linking reactions between acryloyl functionalized bile acids and methoxy poly(ethylene glycol) monomethacrylate (MPEGMA) are conducted by free‐radical photo‐polymerization technique at λ = 350 nm in the presence of 2,2‐Dimethoxy‐2‐phenylacetophenone (DMPA) as an initiator to achieve the desired bile acid‐based polymeric hydrogels. The resulting hydrogels and their intermediates are characterized by Fourier transform infrared (FT‐IR) and Proton nuclear magnetic resonance (¹H‐NMR) spectroscopies. The swelling and thermal behavior of the obtained hydrogels indicates that the hydrogel starting from cholic acid is more swellable and has enhanced thermostability compared to others. Thus, the results of this study offer beneficial insights to researchers working in particularly bio‐medical industry.     

Reaction efficiency of organic alkalis with various classes of lipids during thermally assisted hydrolysis and methylation

Reaction efficiencies of two organic alkalis, tetramethylammonium hydroxide (TMAH) and trimethylsulfonium hydroxide (TMSH), with lipids during thermally assisted hydrolysis and methylation (THM) were examined focusing on (1) the types of lipids and (2) degree of unsaturation of fatty acid moieties. Different types of lipids such as triglycerides, phospholipids, free fatty acids and cholesteryl esters containing saturated, monounsaturated or polyunsaturated fatty acid (PUFA) residues were subjected to THM-gas chromatography (GC) in the presence of TMAH or TMSH. The obtained results revealed that the THM reaction using TMAH allowed almost quantitative methylation of saturated and monounsaturated fatty acid components independently of the classes of lipids. However, strong alkalinity of TMAH brought about isomerization and/or degradation of PUFA components. In contrast, the use of TMSH was effective to highly sensitive detection of PUFA as well as saturated and monounsaturated fatty acid components contained in triglycerides, phospholipids (phosphatidylcholines) and free fatty acids. On the other hand, TMSH was proved to react hardly with any kind of fatty acid residues in cholesteryl esters due to their steric hindrance.     

生物降解材料胆酸-乳酸共聚物的热性能研究

通过直接熔融共聚法合成了系列的不同乳酸／胆酸组成比（LA／CA）的胆酸．乳酸共聚物,用DSC、TG等手段研究生物降解材料胆酸-乳酸共聚物的热性能。结果表明,共聚物的热性能与其组成、结构有关。LA／CA小的多核共聚物无明显熔融峰,热失重分两步进行;LA／CA大的单核共聚物出现明显双头熔融峰,其热失重一步进行,其Tg随着LA／CA增加而升高。     

Polycondensation of α‐amino acid esters in the presence of yttrium triflate as a Lewis acid

To develop polycondensation methods for poly(α‐amino acid)s, we describe a first examination to use yttrium triflate as a Lewis acid for polycondensation of α‐amino acid esters. In the absence of Lewis acid, no polycondensation of 2‐methoxyphenyl glycinate ( 1b ) at room temperature proceeded. While the polycondensation of 1b was carried out with 5 mol % yttrium triflate, a condensation product of glycine was obtained in 16% yield. Although polycondensation of 4‐nitrophenyl L ‐leucinate ( 1c ) and 4‐nitrophenyl L ‐valinate ( 1d ) were also promoted with 5 mol % yttrium triflate, the condensation products of both α‐amino acid esters were obtained in only a few percent yield. When 1d was polymerized in the presence of 100 mol % yttrium triflate, high molecular weight poly(L ‐valine) was obtained in 91% yield. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4731–4735, 2006