本發明係有關於一種式(I)之稠合雙環或多環化合物:其中,A、B、C、X、Y、m及n係定義於本文中。本發明亦揭露一種抑制EGFR激酶活性的方法,以及一種以這些化合物治療癌症之方法。Fused bicyclic or tricyclic compounds of formula (I): wherein A, B, C, X, Y, m, and n are defined herein. Also disclosed are a method for inhibiting EGFR kinase activity and a method for treating cancer with these compounds.