酶促合成肽的研究 II: 含羧基侧链氨基酸的肽的酶促合成

用嗜热菌酶酶促合成了一系列含门冬氨酸、谷氨酸的肽. 实验证明, 缩合反应中羧基组份中的门冬氨酸β-羧基或谷氨酸γ-羧基毋需保护. 同时也研究了邻近氨基酸残基对缩合反应的影响.     

基于“一石二鸟”策略的羧基无痕导向其邻位C—H键官能团化反应

C—H键作为有机化合物的基本单元,实现其直接的C—H键官能团化反应是简洁的合成方法.羧酸广泛存在于自然界,基于羧基的导向基团与离去基团双重角色所驱动的过渡金属催化羧酸邻位C—H键官能团化可控合成,不仅规避了C—H键活化过程中导向基团的额外引入与移除,也彰显了基于羧基“一石二鸟”策略的C—H键活化简洁性与脱羧绿色性.因此,基于“一石二鸟”策略的羧基无痕导向其邻位C—H键官能团化反应,能为可控定向合成提供新的策略和方法,在合成化学上具有显著意义.根据参与反应的偶联底物类型,分别介绍了基于“一石二鸟”策略的过渡金属催化羧酸邻位C—H键活化与含重键试剂、芳基化试剂及含杂原子试剂的反应,并对相关的一些反应机理进行了探讨.     

含悬挂羧基手臂聚乳酸材料的合成与血小板粘附性研究

制备了乳酸-β-苹果酸共聚物,并在此基础上进一步修饰合成了含悬挂羟基(PLMAHE)以及悬挂羧基(PCA-PLA)的聚乳酸共聚物,利用原子力显微镜及环境扫描电镜,观察了聚合物膜的表面形貌以及粘附在聚合物膜上的血小板数量与形态.结果表明含悬挂羟基材料表面粘附血小板时发生聚集并有伪足生成,含悬挂羧基材料表面血小板粘附数量较少且形态正常,有望成为优良的抗凝血材料.     

EDTA冠醚衍生物(Ⅴ)——EDTA-二氨基二苯并冠醚缩聚物的合成及其对金属离子吸附行为初探

在环上含多羧基的冠状聚合物能吸附海水中铀。我们继前文合成了一类在主链上含多个羧甲基的聚酰胺酸3_(a-c)。为了考查冠醚环和羧基对聚合物吸附金属离子的影响,还制备了无冠醚环的3_d,以及3_(a-d)的无羧基衍生物聚酰亚胺4_(a-d)作对照物。其合成路线如下:     

N,N-二{亚烷基氧羰基苯基-5-[10,15,20-三(4-氯苯基)]卟啉基}-5-氟尿嘧啶的合成与表征

用对氯苯甲醛和对羧基苯甲醛为原料,合成了周边含羧基苯基的不对称卟啉中间体,然后再与5-氟尿嘧啶反应,合成了两种亚烷基链长不同的标题化合物,产率为22.1%和19.8%.产物结构由元素分析、红外光谱、紫外可见光谱、核磁共振谱和质谱表征确认.同时对目标化合物的合成条件进行了研究,结果表明,在以DMF为溶剂、反应温度在125℃、反应时间8h条件下,反应产率较高.     

酶促合成肽的研究 Ⅱ.含羧基侧链氨基酸的肽的酶促合成

用嗜热菌酶酶促合成了一系列含门冬氨酸、谷氨酸的肽。实验证明,缩合反应中羧基组份中的门冬氨酸β-羧基或谷氨酸γ-羧基毋需保护。同时也研究了邻近氨基酸残基对缩合反应的影响。     

4种含羧基酰腙化合物的合成、表征和抑菌活性

4种含羧基酰腙化合物的合成、表征和抑菌活性;酰腙;合成;表征;抑菌活性     

改性吐温-20的合成及其乳化性能

利用羟基硅油的羟基与丁二酸酐反应,合成带有羧基的改性羟基硅油,其羧基与吐温-20分子中的羟基发生酯化反应,合成了含改性羟基硅油的改性吐温-20。乳化实验结果表明,羟基硅油改性吐温-20比吐温-20具有更好的乳化效果,离心分离稳定性更好。     

侧链为端羧基聚乙二醇的梳形聚氨酯的合成与表征

以L-赖氨酸、乙二胺和端羧基聚乙二醇(PEG)为原料合成一种带聚乙二醇侧链的二元胺扩链剂(Lys-NH-PEG),然后以4,4'-二苯基甲烷二异氰酸酯(MDI)和Lys-NH-PEG为硬段,聚碳酸酯二醇(PCD)为软段,制备一种含端羧基聚乙二醇侧链的梳形聚氨酯.对所合成聚氨酯材料进行傅立叶变换红外光谱(FTIR)、氢核磁共振谱(1H-NMR)、凝胶渗透色谱(GPC)测试,测试结果表明得到了目标聚合物.该聚合物能在水中形成胶体,并能化学接枝白蛋白,表明所合成的聚氨酯的PEG侧链端羧基具有反应活性.这种具有可反应性的聚氨酯为进一步接枝生物分子以提高生物相容性提供了广阔的空间.     

对羧基偶氮氯膦与镍的络合物的合成及其极谱行为

1 引 言 变色酸双偶氮试剂用于络合物极谱行为的研究并不鲜见,对镍的研究也有报道.本文设计合成并提纯了新试剂对羧基偶氮氯膦(CPApK),将其用于镍的络合物极谱行为的研究,拟定了镍的测定方法,该方法灵敏度高,线性范围宽,可直接测定铝合金中的镍.2 络合剂CPApK的合成及纯化2.1 络合剂的合成 称取1.0g对氨基苯甲酸于100 mL烧杯中,加入 3.5 mL水及 1.7 mL浓盐酸,搅匀,于冰盐浴上冷却至0℃,在剧烈搅拌下,不断滴入含0.5g亚硝酸钠的水溶液重氮化,保持0℃,备用.     

Scope of the formal [3+2] cycloaddition for the synthesis of five-membered ring of functionalized indanes

We report our research about the synthesis of functionalized indanes in the pentagonal ring by a formal [3+2] cycloaddition using benzhydrols and styrene derivatives with electron-withdrawing groups joined to C-β, such as carboxyl, carboxymethyl, carbonyl of ketones, and nitro groups. We also report the configurational assignment of the indanic structures synthesized using several experiments of NMR.     

Modification of polyhedral oligomeric silsesquioxane derivatives with heck reaction as possible new bio-hybrid materials

Abstract

The regioselective synthesis of Polyhedral oligomeric silsesquioxane (POSS)-based norbornyl imide derivatives through palladium catalyzed Heck coupling reaction was reported on an effective synthetic method to organic–inorganic bio-hybrids serving as advanced materials. The reaction of POSS-based imide derivatives with various aryl iodides catalyzed by palladium acetate in the presence of triethyl amine, as the base, in DMF afforded the products in moderate yields. All new POSS derivatives were structurally characterized by FTIR, ¹H, ¹³C NMR, HRMS and GC/MS analyses.     

新型N-甲基-N-烯丙基吗啡啉季铵盐类离子液体的合成

离子液体对某些无机和有机物溶解性能好、液态温度和电化学窗口范围宽、热稳定性高、易制备,因而近年来成为国内外研究的热点,目前的离子液体大多由烷基吡啶或双烷基咪唑季铵盐阳离子与氯铝酸根、氟硼酸根、六氟磷酸根以及其它大的阴离子构成,在季铵盐类离子液体中,     

TiCl4-promoted tandem carbonyl or imine addition and Friedel-Crafts cyclization: synthesis of benzo-fused oxabicyclooctanes and nonanes

A new and convenient synthesis of benzo-fused 8-oxabicyclo[3.2.1]octane and 9-oxabicyclo[4.2.1]nonane derivatives are described. The reaction involved a TiCl(4)-mediated tandem carbonyl or imine addition followed by a Friedel-Crafts cyclization to provide these functionalized derivatives in good to excellent yields and high diastereoselectivity.     

红紫素-18酰亚胺衍生物的合成

以脱镁叶绿酸甲酯为原料, 通过对其3-位乙烯基的氧化, 得到3-(2,2-二甲氧基乙基)-3-去乙烯基脱镁叶绿酸甲酯, 经过甲酸处理得到3-(2-氧代乙基)-3-去乙烯基脱镁叶绿酸甲酯, 选择适当的条件, 通过Grignard 反应合成了对应的3-(2-羟基烷基)-3-去乙烯基脱镁叶绿酸甲酯. 实验结果表明: 3-(2-氧代乙基)-3-去乙烯基脱美叶绿酸甲酯和Grignard试剂的反应, 只要反应条件控制得当, 13²-位的甲氧甲酰基不会脱去. 结合E环的改造, 将其转变成酸酐环进而转变成N-取代的酰亚胺环. 目标化合物的合成也可以将3-(2,2-二甲氧基乙基)-去乙烯基脱镁叶绿酸甲酯转变成N-取代的酰亚胺后, 再和Grignard试剂反应, 完成目标化合物的合成. 合成的一系列化合物具有长波长的紫外吸收. 化合物的结构变化对紫外吸收的影响作了相应的讨论. 合成的新化合物均由核磁共振、红外光谱、元素分析予以证实.     

Synthesis of 2-Ferrocenyl-2-(Dialkyl Hydroxymethyl)D-1,3-Dithianes

The reactions of lithiated 2-ferrocenyl-1,3-dithiane with alkyl carbonyl compounds are studied. Fifteen of title compounds which are new ferrocene derivatives were synthesized and structurally characterized by elemental analysis, IR and 1H NMR spectra. The 1H NMR spectra of the dithiane compounds are briefly discussed.     

Generation and trapping of tricyclo[3.3.0.0]oct-1(5)-ene derivatives containing carbonyl functionalities

Two new functionalized highly pyramidalized tricyclo[3.3.0.0^3,7]oct-1(5)-ene derivatives containing carbonyl functionalities have been trapped as Diels-Alder adducts, although they failed to dimerize. An interesting fragmentation of the bisnoradamantane skeleton to norbornane derivatives has also been observed.     

Azasteroids. Reaction of Chiral N,N-Maleoyl Amino Acids with 1-(1-Trimethylsiloxyvinyl)-3,4-dihydronaphthalene

Summary. The cycloaddition between N,N-maleoyl amino acid esters and 1-(1-trimethylsiloxyvinyl)-3,4-dihydronaphthalene gave 11-(trimethylsiloxy) derivatives of 16-azaestra-1,3,5(10)-trienes. These were transformed by desilylation into the parent 11-oxo-derivatives, which reacted with hydroxylamines to 11-hydroxyimino derivatives. The stereochemistry of the products was elucidated using different NMR methods, HPLC, CD, X-ray structure analysis, and calculations. It was found that mixtures of diastereoisomers were obtained from these cycloadditions. Reactions using chiral maleoyl amino acid derivatves did not change this result. The chiral center did not provoke stereoselectivity, probably caused by the flexibility of the chiral side chain. A directing influence of the side chain was found only in reactions with derivatives of phenylalanine. This might be explained as an interaction between the aromatic system and the carbonyl groups of the imide moiety. This interaction kept the aromatic ring in its position in the final product, and was found in the X-ray crystallographic analysis, and agreed with results of calculations.     

Azasteroids. Reaction of Chiral N,N-Maleoyl Amino Acids with 1-(1-Trimethylsiloxyvinyl)-3,4-dihydronaphthalene

The cycloaddition between N,N-maleoyl amino acid esters and 1-(1-trimethylsiloxyvinyl)-3,4-dihydronaphthalene gave 11-(trimethylsiloxy) derivatives of 16-azaestra-1,3,5(10)-trienes. These were transformed by desilylation into the parent 11-oxo-derivatives, which reacted with hydroxylamines to 11-hydroxyimino derivatives. The stereochemistry of the products was elucidated using different NMR methods, HPLC, CD, X-ray structure analysis, and calculations. It was found that mixtures of diastereoisomers were obtained from these cycloadditions. Reactions using chiral maleoyl amino acid derivatves did not change this result. The chiral center did not provoke stereoselectivity, probably caused by the flexibility of the chiral side chain. A directing influence of the side chain was found only in reactions with derivatives of phenylalanine. This might be explained as an interaction between the aromatic system and the carbonyl groups of the imide moiety. This interaction kept the aromatic ring in its position in the final product, and was found in the X-ray crystallographic analysis, and agreed with results of calculations.     

红紫素-18酰亚胺衍生物的化学修饰

以脱镁叶绿酸-a甲酯为原料, 通过对其3-位乙烯基的氧化, 得到了3-甲酰基脱镁叶绿酸甲酯, 利用Wittig反应合成了对应的3-(2-取代的乙烯基)脱镁叶绿酸甲酯. 结合E环的改造, 将其转变成酸酐环进而转变成N-取代的酰亚胺环. 目标化合物具有亲水区和疏水区两部分, 吸收波长明显向红位移. 合成得到的红紫素-18酰亚胺衍生物有可能成为光动力疗癌的理想光敏剂. 合成的新化合物均由核磁共振、红外光谱、元素分析和质谱予以证实.