G-quadruplex DNA-based asymmetric catalysis of michael addition: Effects of sonication, ligands, and co-solvents.
G-quadruplex DNA-based asymmetric catalysis of michael addition: Effects of sonication, ligands, and co-solvents.
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DOI：
10.1002/btpr.2281
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发表时间：
2016-07-08
影响因子：
2.9
通讯作者：
Shen K
中科院分区：
文献类型：
--
作者：
Zhao H;Shen K
利用双链DNA分子作为手性支架构建金属-生物大分子杂化催化剂用于不对称合成的研究日益受到人们的关注。最近的几项研究还评价了G-四链DNA催化剂在不对称Diels-Alder和Friedel-Craft反应中的应用。然而，对于不同的寡核苷酸、盐(如氯化钠和氯化钾)、金属配体和共溶剂如何影响四链DNA杂化催化剂的催化性能，目前还缺乏了解。在本研究中，我们旨在系统地评价不对称Michael加成反应中的这些关键因素，并利用圆二色谱(CD)和凝胶电泳法检测DNA的构象和分子变化。以5‘-G3(TTAG3)3-3’(G4DNA1)为催化剂，在含有50 mMKCl40μM[Cu(Dmbipy)(NO3)2]的20 mM MOPS(pH 6.5)中催化2-酰基咪唑1a与丙二酸二甲酯的反应，产率可达95%，对映体过量(Ee)为50%。基于G-四链体的杂化催化剂为不对称催化提供了一种新的工具，但未来的机理研究有待于进一步提高催化效率。本工作系统地研究了非共价络合G-四链催化剂催化的不对称Michael加成反应，并发现了预超声对催化效率的影响。
There is an escalating interest of using double stranded DNA molecules as a chiral scaffold to construct metal-biomacromolecule hybrid catalysts for asymmetric synthesis. Several recent studies also evaluated the use of G-quadruplex DNA-based catalysts for asymmetric Diels-Alder and Friedel-Crafts reactions. However, there is still a lack of understanding of how different oligonucleotides, salts (such as NaCl and KCl), metal ligands and co-solvents affect the catalytic performance of quadruplex DNA-based hybrid catalysts. In this study, we aim to systematically evaluate these key factors in asymmetric Michael addition reactions, and to examine the conformational and molecular changes of DNA by circular dichroism (CD) spectroscopy and gel electrophoresis. We achieved up to 95% yield and 50% enantiomeric excess (ee) when the reaction of 2-acylimidazole 1a and dimethylmalonate was catalyzed by 5’-G3(TTAG3)3-3’ (G4DNA1) in 20 mM MOPS (pH 6.5) containing 50 mM KCl and 40 μM [Cu(dmbipy)(NO3)2], and G4DNA1 was pre-sonicated in ice bath for 10 min prior to the reaction. G-quadruplex-based hybrid catalysts provide a new tool for asymmetric catalysis, but future mechanistic studies should be sought to further improve the catalytic efficiency. The current work presents a systematic study of asymmetric Michael addition catalyzed by G-quadruplex catalysts constructed via non-covalent complexing, and an intriguing finding of the effect of pre-sonication on catalytic efficiency.
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影响因子：
8.4
作者：
Oelerich, Jens;Roelfes, Gerard
通讯作者：
Roelfes, Gerard
影响因子：
15
作者：
Mantri, Yogita;Lippard, Stephen J.;Baik, Mu-Hyun
通讯作者：
Baik, Mu-Hyun
影响因子：
21.8
作者：
Boersma, Arnold J.;Coquiere, David;Roelfes, Gerard
通讯作者：
Roelfes, Gerard
影响因子：
16.6
作者：
Boersma, Arnold J.;Feringa, Ben L.;Roelfes, Gerard
通讯作者：
Roelfes, Gerard
DOI：
10.1039/dt9780001127
发表时间：
1978-01-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
影响因子：
--
作者：
KIERNAN, PM;LUDI, A
通讯作者：
LUDI, A