An epidermal growth factor receptor (EGFR) family tyrosine kinase inhibitor comprising a functional group that can bind to the serine S797 residue in EGFR having a C797S mutation or the serine S805 residue in HER2 having a C805S mutation.本發明係關於一種表皮生長因子受體(EGFR)族群之酪胺酸激酶抑制劑,其包含可結合至具有C797S突變之EGFR中的絲胺酸S797殘基或具有C805S突變之HER2中的絲胺酸S805殘基的官能基。