Are suitable for the treatment of diseases characterized by excessive or abnormal cell proliferation, the present invention provides compounds of the general formula (1) (Wherein R 1 ~R 3 is as defined in claim 1), including its use for the preparation of a medicament having the above properties and,.本発明は、過度又は異常な細胞増殖により特徴付けられる疾患の治療に適切である、一般式(1)の化合物(式中R1~R3は請求項1で定義される)、及び上記特性を有する薬剤の調製のためのその使用を含む。