A visible‐light‐mediated photoredoxMinisci‐typealkylation with ethers as the alkylating reagent is reported. User‐friendly LiBr has been found to be the key promoter for this radical coupling. The reaction exhibits broad functional group tolerance for both C2 and C4 couplings/alkylations of quinolines. Mechanistic studies suggest that the bromide additive could not only dramatically enhance the reaction
A novel class of phosphodiesterase 10A (PDE10A) inhibitors with improved metabolic stability in mouse liver microsomes were designed and synthesized starting from 2-(4-[1-methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl]phenoxy}methyl)quinoline (MP-10). Replacement of the phenoxymethyl part of MP-10 with an oxymethyl phenyl unit led to the identification of 2-[4-([1-methyl-4-(pyridin-4-yl)-1H-pyrazol-3-yl]oxy}methyl)phenyl]quinoline (14), which showed moderate PDE10A inhibitory activity with improved metabolic stability in mouse and human liver microsomes over MP-10. Compound 14 showed high concentrations in plasma and brain after intraperitoneal administration and dose-dependently attenuated the hyperlocomotion induced by phencyclidine in mice, and oral administration of 14 (0.1, 0.3 mg/kg) also improved visual-recognition memory impairment in mice.