Purity >99%. The casein kinase 1 (CK1) family of kinases regulate diverse processes, particularly related to circadian rhythms and sensitivity to amphetamines. PF-670462 is a potent inhibitor of the CK1 isoforms CK1e and CK1Delta (IC50 = 7.7 and 14 nM, respectively). It less effectively inhibits a wide variety of related or common kinases. Through its effects on CK1, PF-670462 disrupts circadian rhythms in cells and animals. It also blocks the locomotor response to amphetamines in mice.