The synthesis and biological evaluation of 1-C-alkyl-l-arabinoiminofuranoses, a novel class of α-glucosidase inhibitors
摘要:
The asymmetric synthesis of 1-C-alkyl-L-arabinoiminofuranoses 1 was achieved by asymmetric allylic alkylation (AAA), ring closing metathesis (RCM), and Negishi cross coupling as key reactions. Some of the prepared compounds showed potent inhibitory activities towards intestinal maltase, with IC50 values comparable to those of commercial drugs such as acarbose, voglibose, and miglitol, which are used in the treatment of type 2 diabetes. Among them, the inhibitory activity (IC50 = 0.032 mu M) towards intestinal sucrase of 1c was quite strong compared to the above commercial drugs. (C) 2010 Elsevier Ltd. All rights reserved.
Carbonylative Coupling of Alkyl Zinc Reagents with Benzyl Bromides Catalyzed by a Nickel/NN
<sub>2</sub>
Pincer Ligand Complex
作者:Thomas L. Andersen、Aske S. Donslund、Karoline T. Neumann、Troels Skrydstrup
DOI:10.1002/anie.201710089
日期:2018.1.15
An efficient catalytic protocol for the three‐component assembly of benzyl bromides, carbon monoxide, and alkyl zinc reagents to give benzyl alkyl ketones is described, and represents the first nickel‐catalyzed carbonylative coupling of two sp3‐carbon fragments. The method, which relies on the application of nickelcomplexed with an NN2‐type pincer ligand and a controlled release of CO gas from a solid
secondary benzylic alcohols via tandem Ni-catalyzed cross-coupling reactions of aromatic 2-pyridyl esters with alkyl zinc reagents and carbonyl group reduction by Ni–H species is achieved. Preliminary mechanistic studies reveal that the Ni–H species is generated in situ via β-hydride elimination of the Negishi reagents. The reaction is catalyzed by bench-stable nickel salts under mild conditions with
Transition metal complexes of N-heterocyclic carbenes, method of preparation and use in transition metal catalyzed organic transformations
申请人:Organ G. Michael
公开号:US20070073055A1
公开(公告)日:2007-03-29
The present invention relates to catalysts of transition metal complexes of N-heterocyclic carbenes, their methods of preparation and their use in chemical synthesis. The synthesis, ease-of-use, and activity of the compounds of the present invention are substantial improvements over in situ catalyst generation. Further, the transition metal complexes of N-heterocyclic carbenes of the present invention may be used as precatalysts in metal-catalyzed cross-coupling reactions.
Synthesis of Aliphatic Carboxamides Mediated by Nickel NN<sub>2</sub>
-Pincer Complexes and Adaptation to Carbon-Isotope Labeling
作者:Karoline T. Neumann、Aske S. Donslund、Thomas L. Andersen、Dennis U. Nielsen、Troels Skrydstrup
DOI:10.1002/chem.201804077
日期:2018.10.9
reagents, stoichiometric carbonmonoxide and amines is described for the first time, which can be adapted to late‐stage carbon‐isotope labeling. This work expands the scope of the highly established palladium‐promoted version of the reaction, by allowing carbon‐sp3 fragments to take part in the three‐component reaction. Finally, the results obtained show a remarkable effect of the pincer ligand for
首次介绍了使用NN 2钳形镍配合物,烷基锌试剂,化学计量一氧化碳和胺开发镍介导的氨基羰基化反应的方法,该方法可用于后期碳同位素标记。通过允许碳sp 3片段参与三组分反应,这项工作扩展了高度确立的钯促进反应的范围。最后,获得的结果显示了钳型配体在用胺进行的还原消除步骤中的显着效果,随后进行了13 C NMR光谱研究。
Differentiating CBr and CCl Bond Activation by Using Solvent Polarity: Applications to Orthogonal Alkyl-Alkyl Negishi Reactions
作者:Niloufar Hadei、George T. Achonduh、Cory Valente、Christopher J. O'Brien、Michael G. Organ
DOI:10.1002/anie.201100705
日期:2011.4.18
A pot to share: A CalkylClbond can be rendered “dormant” or “active” in the Negishialkyl–alkyl cross‐coupling by a simple solventpolarity “switch” (see scheme). Adjustment from a 1:2 to a 2:1 solvent ratio of dimethylimidazolidinone:tetrahydrofuran enables orthogonalalkyl–alkylNegishi cross‐coupling strategies to be carried out on bifunctional bromochloroalkanes in one pot at room temperature