Mechanistic Insights from the Gas-Phase Reactivity of Phosphorus-Ylid-Supported Benzylidene Gold Complexes
作者:Alexey Fedorov、Peter Chen
DOI:10.1021/om100224h
日期:2010.7.12
The chemoselectivity as a function of ligand electronic properties was studied for the adducts of phosphorus-ylid-supported gold benzylidenes with methyl vinyl ether by gas-phase collision-induced dissociation experiments. The daughter channels were identified as cyclopropanation, metathesis, and regeneration of the starting benzylidene carbene via olefin loss. The observed product ratios provided linear Hammett plots with a negative slope for the cyclopropanation channel and similar positive p values for metathesis and olefin loss. These results are consistent with the presence of a gold-coordinated cyclopropane intermediate as a global minimum energy structure in the gas phase, from which the pathways to the different products proceed. Additionally, we discuss the anomalous case of the para-dimethylamino gold benzylidene species, which appears to be too stabilized to engage in the reactivity under investigation.
Structure–Activity Relationship Studies of Trisubstituted Isoxazoles as Selective Allosteric Ligands for the Retinoic-Acid-Receptor-Related Orphan Receptor γt
作者:Femke A. Meijer、Annet O.W.M. Saris、Richard G. Doveston、Guido J.M. Oerlemans、Rens M.J.M. de Vries、Bente A. Somsen、Anke Unger、Bert Klebl、Christian Ottmann、Peter J. Cossar、Luc Brunsveld
DOI:10.1021/acs.jmedchem.1c00475
日期:2021.7.8
drawbacks associated with orthosteric modulators. Recently, trisubstitutedisoxazoles were identified as a novel class of allosteric RORγt inverse agonists. This chemotype offers new opportunities for optimization into selective and efficacious allosteric drug-like molecules. Here, we explore the structure–activity relationship profile of the isoxazole series utilizing a combination of structure-based design