The apelin receptor (APJ) is a target for cardiovascular indications. Previously, we had identified a novel pyrazole-based agonist 1 ((S)-N-(1-(cyclobutylamino)-1-oxo-5-(piperidin-1-yl)pentan-3-yl)-1-cyclopentyl-5-(2,6-dimethoxyphenyl)-1H-pyrazole-3-carboxamide hydrochloride) of this GPCR. Systematic modification of 1 was performed to produce compounds with improved potency and ADME properties. Orally
In the course of our research into enzyme-triggeredCO-releasingmolecules (ET-CORMs), we were interested in using 2-acetoxy-5-azido-1,3-cyclohexadiene–Fe(CO)3 (rac-2) as a building block for further structural modification by means of Cu-catalyzed azide–alkyne cycloaddition (CuAAC click chemistry). Treatment of [2-acetoxy-cyclohexadienyl–Fe(CO)3]+[PF6]− with Zn(N3)2, TMS-N3, or NaN3 surprisingly afforded