Provided herein are Pyrrolopyrimidine Compounds having the following structure:wherein R1, R2, R3, and L are as defined herein, compositions comprising an effective amount of a Pyrrolopyrimidine Compound, and methods for treating or preventing breast cancer, more particularly triple negative breast cancer, comprising administering an effective amount of such Pyrrolopyrimidine Compounds to a subject in need thereof.本文提供具有以下結構之吡咯并嘧啶化合物:其中R1、R2、R3及L係如本文所定義;包含有效量之吡咯并嘧啶化合物之組合物;及用於治療或預防乳癌、更具體而言三重陰性乳癌之方法,該等方法包含向有需要之個體投與有效量之該等吡咯并嘧啶化合物。