Identification of alpha-substituted acylamines as novel, potent, and orally active mGluR5 negative allosteric modulators

This Letter describes the identification of a series of novel non-acetylenic mGluR5 negative allosteric modulators based on the alpha-substituted acylamine structure. An initial structure–activity relationship study suggested that (R)-19b and (R)-19j might have good in vitro activity. When administered orally, these compounds were found to have an anxiolytic-like effect in a mouse model of stress-induced hyperthermia.