Triple-negative breast cancer(TNBC)is one of the most aggressive and deadly subtypes of breast cancer.[1-3] So far,there is no small molecule targeted drugs for the treatment of TNBC.In this investigation,a series of 3-(phenylethynyl)-1H-pyrazolo[3,4-d] pyrimidin-4-amine derivatives were designed and synthesized.Structure-activity relationship(SAR)analysis of these compounds led to the discovery of compound 1j,which showed the highest inhibitory potency against the Src kinase and the most potent anti-viability activity against the typical TNBC cell line MDA-MB-231 among all the synthesized compounds.