a Design of novel type II inhibitors inducing DFG-out and αC-helix-out inactive conformations. Crystal structures of dasatinib (b) or its analogs (c, d) with Src in active (b, PDB: 3G5D), DFG-out (c, PDB: 4YBJ) and αC-helix-out (d, PDB: 4YBK) conformation. c Incorporation of trifluoromethyl benzamide group to dasatinib analog II inhibitors lead to DFG-out (dark blue) in contrast to DFG-in (light blue) conformation. d Incorporation of para-phenoxy group to dasatinib analog leads to αC-helix-out (orange) in contrast to αC-helix in (red) conformation.