Ear chalone peptide, including MeVal-Val-Dil-Dap- norephedrines (MMAE) and MeVal-Val-Dil-Dap-Phe (MMAF) are prepared, includes that maleimide capryl-val-cit-PAB connects what ligand by various terminal. Obtained ligand drug conjugate is all active in vitro and in vivo.製備耳抑素肽,包括MeVal-Val-Dil-Dap-去甲麻黃鹼(MMAE)和 MeVal-Val-Dil-Dap-Phe(MMAF),通過各種接頭包括馬來酰亞胺癸酰基-val-cit-PAB將其連接於配體。得到的配體藥物偶聯物在體外和體內都有活性。