The present invention provides 4-substituted-3-{phenyl[(heterocyclylmethoxy)imino]methyl}-1,2,4-oxadiazol-5(4H)-one derivatives of formula (I) wherein A represents a pyridyl or thiazole group and X1, Y1 to Y5 represent independently different substituents.本發明提供式(I)之4-經取代-3-{苯基[(雜環基甲氧基)亞胺基]甲基}-1,2,4-二唑-5(4H)-酮衍生物其中A代表吡啶基或噻唑基,且X1、Y1至Y5獨立地代表不同取代基。