MS-PPOH is a potent and selective cytochrome P450 ( CYP ) epoxygenase inhibitor. MS-PPOH inhibits CYP2C8 and CYP2C9 with IC 50 s of 15 and 11 μM, respectively. MS-PPOH is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.