Hydrogen bonding is ubiquitous throughout nature and serves as a versatile platform for accessing chemicalreactivity. In leveraging this force, chemists have utilized organocatalysts to expand the spectrum of chemicalreactivity enabled by hydrogen bonding and at the extreme proton transfer. Despite this broad utility, exploiting charge as a hydrogen-bond activation strategy is unknown for squaramide
作者:Garrett, Taylor R.、Gilchrist, Jayson、McKenzie, Andre D. J.、Larik, Fayaz Ali、Danon, Jonathan J.、Werry, Eryn L.、Kassiou, Michael
DOI:10.1002/cmdc.202400163
日期:——
Despite their acknowledged significance in the inflammatory signalling cascade across a range of disease states, P2X7R antagonists have not yet proven to be effective in clinical trials. In this study, we present findings on P2X7 receptor antagonists that are based on a core adamantyl‐cyanoguanidine‐quinoline lead. To investigate the specific features of the cyanoguanidine moiety that influence compound potency we carried out a structure‐activity relationship (SAR) study. Compound potency was assessed using an in vitro dye‐uptake assay measuring P2X7R pore formation. While none of the compounds displayed superior potency to the lead, we established key structural requirements for potent P2X7R antagonism. An additional SAR using different aryl groups was performed based on the promising activity displayed by the squaramide derivative.
Dicyclopentyl Dithiosquarate as an Intermediate for the Synthesis of Thiosquaramides
作者:Michael Rombola、Viresh H. Rawal
DOI:10.1021/acs.orglett.7b03549
日期:2018.2.2
for the synthesis of a variety of thiosquaramides from a common dithionated intermediate. Both diaryl thiosquaramides and bifunctional thiosquaramides are readily accessed from dicyclopentyl dithiosquarate via two addition–elimination reactions. The convenient handling characteristics and relative stability of associated intermediates enable an operationally simple thiosquaramide preparation. Bifunctional
作者:Katherine I. Taylor、Jordan S. Ho、Hallie O. Trial、Alan W. Carter、Laura L. Kiessling
DOI:10.1021/jacs.2c05691
日期:2023.11.22
Probes that covalently label protein targets facilitate the identification of ligand-binding sites. Lysine residues are prevalent in the proteome, making them attractive substrates for covalent probes. However, identifying electrophiles that undergo amine-specific, regioselective reactions with bindingsite lysine residues is challenging. Squarates can engage in two sequential conjugate addition–elimination