The present invention provides a new class of compound of formula I, the pharmaceutical composition containing such compound and the methods for treating or preventing disease or obstacle using such compound; the disease or obstacle and abnormal kinase are out of control related, more particularly, to the disease or obstacle of B-Raf abnormal activation.本發明提供了一類新的式I化合物、含有此類化合物的藥物組合物以及採用此類化合物治療或預防疾病或障礙的方法,所述疾病或障礙與激酶活性異常或失控有關,尤其是涉及B-Raf異常激活的疾病或障礙。