design and develop new and more potentEGFRinhibitors with improved anti-tumor activity. Here we describe the design and synthesis of two series of 4-benzothienyl amino quinazolines as new analogues of the EGFRinhibitorGefitinib. The anti-tumor activity of these novel Gefitinib analogues in 6 human cancer celllines was examined. Compared with the parental Gefitinib, most of the new compounds show