Synthesis of heteroaromatic tropeines and heterogeneous binding to glycine receptors
摘要:
Heteroaromatic carboxylic esters of (nor) tropine were synthesized. Tropine esters displaced [(3)H]strychnine binding to glycine receptors of rat spinal cord with low Hill slopes. Two-site displacement resulted in nanomolar IC(50,1) and micromolar IC(50,2) values, and IC(50,2)/IC(50,1) ratios up to 615 depending on the heteroaromatic rings and N-methyl substitution. Nortropeines displayed high affinity and low heterogeneity. IC(50,1) and IC(50,2) values of tropeines did not correlate suggesting different binding modes/sites. Glycine potentiated only the nanomolar displacement reflecting positive allosteric interactions and potentiation of ionophore function. Affinities of three (nor) tropeines were different for glycine receptors but identical for 5-HT(3) receptors. (C) 2009 Elsevier Ltd. All rights reserved.
Expanded scope of heterocyclic biaryl synthesis via a palladium-catalysed thermal decarboxylative cross-coupling reaction
作者:Marie Kissane、Orla A. McNamara、David Mitchell、David M. Coppert、Humphrey A. Moynihan、Kurt T. Lorenz、Anita R. Maguire
DOI:10.1016/j.tetlet.2011.11.051
日期:2012.1
The palladium-catalysed decarboxylativecross-coupling of heterocyclic aromaticcarboxylates and aryl halides is described. The cross-coupling proceeds under relatively mild conditions using catalytic Pd(0) and tetrabutylammonium bromide (TBAB). Utilizing a mixed solvent system consisting of N,N-dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP), the cross-coupling system operated at temperatures