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 共查询到19条相似文献,搜索用时 62 毫秒
1.
黄强  隆泉  郑保忠 《化学进展》2004,16(2):236-242
介绍了固相有机合成中的连接基团,特别是带有隔离单元的连接基团、无痕迹连接基团、安全拉手型连接基团和复合型连接基团的基本概念、发展近况以及它们的应用.  相似文献   

2.
聚合物固载相转移催化剂在有机合成中的应用   总被引:1,自引:0,他引:1  
本文综述了聚合物固载相转移催化剂在有机合成中的应用,包括亲核取代反、应、加成反应。消除反应、氧化还原反应等。  相似文献   

3.
聚合物媒介有机合成是近20年发展起来的有机合成新方法。该法具有收率高、选择性好、产物容易分离和载体可回收重用等优点。目前已广泛地用于精细有机合成和天然产物合成。著名的固相法多肽合成是其中一个实例,研究者Merrifield因此荣获1984年度诺贝尔化学奖。  相似文献   

4.
一、前言近年来,利用酶进行有机合成反应,尤其是催化不对称合成反应,使分子中引入手性中心,  相似文献   

5.
综述了目前用于固相有机合成中聚合物支载的功能基团的各种分析鉴定方法。  相似文献   

6.
本文就三价有机横 盐, 包括二芳基、芳基全氟烷基、芳基烯基、芳基炔基和芳基烯丙基碘 盐以及碘叶立德在有机合成上有用的反应进行综述. 这些反应包括C-, O-,N-和S-芳基化, 全氟烷基、烯基、炔基、烯丙基和亚烷基转移反应等.  相似文献   

7.
本文考察了固载化聚乙二醇季铵盐作为相转移催化剂在咪唑N-烷基化反应,Williamson混合醚的合成以及卤素转换反应中的应用,着重研究了改变反应条件对催化反应的影响,就催化剂的重复使用能力和催化剂结构对其催化效率的影响也略作探讨。实验证明,本催化剂有较高的催化活性,有实际应用价值。  相似文献   

8.
钐试剂在有机合成中的应用   总被引:2,自引:0,他引:2  
本文综述了钐试剂在有机合成中的应用,包括还原反应,碳-碳键形成反应以及催化作用。  相似文献   

9.
聚合物支载的不对称有机合成   总被引:3,自引:0,他引:3  
聚合物支载的不对称有机合成比相应的小分子合成体系有独特的优越性。本文综述了近10年来取得了较大进展的聚合物支载的不对称有机合成体系。  相似文献   

10.
本文重点介绍了目前实验室和市场上可用于固相组合合成的含羟基的聚合物载体及其主要的化学反应性能。  相似文献   

11.
Carbohydrates contain numerous hydroxyl groups and sometimes amine functionalities which lead to a variety of complex structures. In order to discriminate each hydroxyl group for the synthesis of complex oligosaccharides, protecting group manipulations are essential. Although the primary role of a protecting group is to temporarily mask a particular hydroxyl/amino group, it plays a greater role in tuning the reactivity of coupling partners as well as regioselectivity and stereoselectivity of glycosylations. Several protecting groups offer anchimeric assistance in glycosylation. They also alter the solubility of substrates and thereby influence the reaction outcome. Since oligosaccharides comprise branched structures, the glycosyl donors and acceptors need to be protected with orthogonal protected groups that can be selectively removed one at a time without affecting other groups. This minireview is therefore intended to provide a discussion on new protecting groups for amino and hydroxyl groups, which have been introduced over last ten years in the field of carbohydrate synthesis. These protecting groups are also useful for synthesizing non‐carbohydrate target molecules as well.  相似文献   

12.
13.
The growing interest in synthetic peptides has prompted the development of viable methods for their sustainable production. Currently, large amounts of toxic solvents are required for peptide assembly from protected building blocks, and switching to water as a reaction medium remains a major hurdle in peptide chemistry. We report an aqueous solid‐phase peptide synthesis strategy that is based on a water‐compatible 2,7‐disulfo‐9‐fluorenylmethoxycarbonyl (Smoc) protecting group. This approach enables peptide assembly under aqueous conditions, real‐time monitoring of building block coupling, and efficient postsynthetic purification. The procedure for the synthesis of all natural and several non‐natural Smoc‐protected amino acids is described, as well as the assembly of 22 peptide sequences and the fundamental issues of SPPS, including the protecting group strategy, coupling and cleavage efficiency, stability under aqueous conditions, and crucial side reactions.  相似文献   

14.
The choice of protecting groups is one of the decisive factors in the successful realization of a complex, demanding synthetic project. The protecting groups used influence the length and efficiency of the synthesis and are often responsible for its success or failure. A wide range of blocking groups are currently available for the different functional groups; however, an overall strategy combining these different masking techniques in an advantageous and reliable manner has never been proposed or at best only for individual cases. This review attempts to make a contribution to filling this gap. First a very short overview of the most commonly used protecting groups will be given, in which they are classified according to their lability and not according to the functional group they protect. This classification clarifies coherent concepts for the development of blocking strategies. On the basis of this brief summary reliable strategies will then be illustrated and developed with selected examples from the recent literature by which protecting groups may be combined successfully and advantageously in synthetic projects of differing degrees of complexity and difficulty.  相似文献   

15.
A new route to synthesis of various mono-N-substituted hydrazines and hydrazides by involving in a new C−N bond formation by using N-amino-1,8-naphthalimide as a regenerated precursor was invented. Aniline and phenylhydrazines are reproduced upon reacting these individually with 1,8-naphthalic anhydride followed by hydrazinolysis. The practicality and simplicity of this C−N dihalo alkanes; developed a synthon for bond formation protocol was exemplified to various hydrazines and hydrazides. N-amino-1,8-naphthalimide is suitable synthon for transformation for selective formation of mono-substituted hydrazine and hydrazide derivatives. Those are selective mono - amidation of hydrazine with acid halides; mono-N-substituted hydrazones from aldehydes; synthesis of N-aminoazacycloalkanes from acetohydrazide scaffold and inserted to hydroxy derivatives; distinct synthesis of N,N-dibenzylhydrazines and N-benzylhydrazines from benzyl halides; synthesis of N-amino-amino acids from α-halo esters. Ecofriendly reagent N-amino-1,8-naphthalimide was regenerated with good yields by the hydrazinolysis in all procedures.  相似文献   

16.
Benzyloxycarbonyl-glutamylpeptide p-nitrophenylesters were prepared from protected amino acids, e.g.: p-nitrophenyl-glutamate as carboxyl component and aminoacid or peptide p-nitrophenylesters as amino components by different kinds of peptide coupling methods. Mixed carbonic anhydride and azide methods gave good results. The p-nitrophenylesters existed as temporary protecting groups, so the peptide couplings proceeded together with simultaneous activation. The conditions and applications of the procedure are discussed. The peptides having one or more active ester groups were used to form amides by their aminolysis with derivatives of ethylamine or were polycondensated (after deprotection) to obtain polypeptides.  相似文献   

17.
18.
A new kind of photolabile protecting group (PLPG) for carboxyl moieties was designed and synthesized as the linker between resin and peptide. This group can be used for the protection of amino acid carboxyl groups. The peptide was synthesized on Nph (2-hydroxy-3-(2-nitrophenyl)-heptanoic acid)-derivatized resins and could be cleaved under UV exposure, thus avoiding the necessity for harsh acid-mediated resin cleavage. The PLPG has been successfully used for solid-phase synthesis of peptides.  相似文献   

19.
高分子表面活性剂的合成   总被引:8,自引:0,他引:8  
金勇  董阳  魏德卿 《化学进展》2005,17(1):0-156
介绍了高分子表面活性剂的合成方法及其不同于低分子表面活性剂的特点,重点从离子聚合、活性自由基聚合、缩合聚合、开环聚合、高分子化学反应、自由基胶束聚合等角度综述了近几-来高分子表面活性剂的合成研究进展.  相似文献   

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