Synthesis and evaluation of 4-substituted piperidines and piperazines as balanced affinity μ opioid receptor (MOR) agonist/δ opioid receptor (DOR) antagonist ligands
摘要:
In this letter, we describe a series of 4-substituted piperidine and piperazine compounds based on tetrahydroquinoline 1, a compound that shows balanced, low nanomolar binding affinity for the mu opioid receptor (MOR) and the delta opioid receptor (DOR). We have shown that by changing the length and flexibility profile of the side chain in this position, binding affinity is improved at both receptors by a significant degree. Furthermore, several of the compounds described herein display good efficacy at MOR, while simultaneously displaying DOR antagonism. The MOR agonist/DOR antagonist has shown promise in the reduction of negative side effects displayed by selective MOR agonists, namely the development of dependence and tolerance. (C) 2013 Elsevier Ltd. All rights reserved.
Air-Stable, Phosphine-Free Anionic Palladacyclopentadienyl Catalysts: Remarkable Halide and Pseudohalide Effects in Stille Coupling
作者:Catherine M. Crawforth、Ian J. S. Fairlamb、Anant R. Kapdi、José Luis Serrano、Richard J. K. Taylor、Gregorio Sanchez
DOI:10.1002/adsc.200505325
日期:2006.3
The Stille cross-coupling of allylic and benzyl bromides is shown to proceed efficiently using phosphine-free dinuclear anionicpalladacyclopentadienylcatalysts possessing bridging (N,O)-imidate ligands. The type of bridging anion influences the catalytic activity considerably. Halide anions such as chloride, bromide or iodide also influence the catalytic activity but to a far lesser extent than the
Scope and Limitation of the Microwave-Assisted Catalytic Wittig Reaction
作者:Marcel Hoffmann、Sunetra Deshmukh、Thomas Werner
DOI:10.1002/ejoc.201500310
日期:2015.7
We have developed a microwave-assisted catalyticWittigreaction. In this paper, we give full account of the scope and limitations of this reaction. A screening of various commercially available phosphine oxides as precatalysts revealed Bu3P=O to be the most promising candidate. We tested 10 silanes for the in situ reduction of the phosphine oxide to generate Bu3P as the actual catalyst. Different
我们开发了一种微波辅助催化 Wittig 反应。在本文中,我们充分考虑了该反应的范围和局限性。对各种市售氧化膦作为预催化剂的筛选表明,Bu3P=O 是最有希望的候选者。我们测试了 10 种硅烷原位还原氧化膦以生成 Bu3P 作为实际催化剂。测试不同的环氧化物作为掩蔽碱。在这方面,环己烯氧化物和丁烯氧化物被证明是合适的。该反应可在 125 °C 下进行,但在 150 °C 下可获得更高的产率和 E/Z 选择性。在优化的反应条件下,报道了各种醛类转化为相应烯烃的40多个实例。以高达 88% 的产率获得了具有高 E 选择性的产物。
Ligand-Free Suzuki Coupling of Arylboronic Acids with Methyl (<i>E</i>)-4-Bromobut-2-enoate: Synthesis of Unconventional Cores of HIV-1 Protease Inhibitors
ligand-free Suzuki coupling protocol to unite methyl (E)-4-bromobut-2-enoate with several arylboronic acids has been accomplished. Thus, a number of variously functionalized methyl 4-arylcrotonates have been achieved in high to excellent yields under mild conditions. This method enables the preparation of diverse aryl-substituted cores of HIV-1 protease inhibitors.
Highly (<i>E</i>)-Selective Wadsworth−Emmons Reactions Promoted by Methylmagnesium Bromide
作者:Timothy D. W. Claridge、Stephen G. Davies、James A. Lee、Rebecca L. Nicholson、Paul M. Roberts、Angela J. Russell、Andrew D. Smith、Steven M. Toms
DOI:10.1021/ol802212e
日期:2008.12.4
An experimentally simple protocol for the very highly (E)-selective Wadsworth-Emmonsreaction [(E):(Z) selectivities in excess of 180:1 in some cases] of a range of straight-chain and branched aliphatic, substituted aromatic, and base-sensitive aldehydes via reaction with an alkyl diethylphosphonoacetate and MeMgBr is reported.
Reactions of α,β-unsaturated esters with aldehydes were catalyzed by 0.2 equiv of lithium benzenethiolate in the presence of phenyl trimethylsilyl sulfide to afford the conjugate addition-aldol tandem reaction products in the anti stereoselectivity and good to high yields.