SM1044 is a dihydroartemisinin (DHA) dimer. SM1044 activates caspase , induces apooptosis in RL95-2 and KLE cells. SM1044 inhibits proliferations of cancer cells RL95-2, KLE, HEC-50, HEC-1-A, HEC-1-B, AN3CA, with IC 50 < 3.6 μM. SM1044 inhbits tumor growth in RL95-2 xenograft mouse model.