The 1st core hopping operation was aimed at the Core C part (see red part of Fig. 2) , generating five cores, Core C1, Core C2, Core C3, Core C4, and Core C5, respectively, to replace Core C. The 2nd core hopping operation was aimed at the Core B part (see (1k74) . The binding pocket is defined by those residues that have at least one heavy atom with a distance of 5 Å from the ligand [45] . The ligand GW409544 (in grey color) was extracted from the crystal structure while the ligand Comp#1 (rendered by three colors: grey for Core A; red for Core B; and blue for Core C) was generated by the ''core-hopping'' method. The hydrophobic surface of the receptor is colored in green. blue part of Fig. 2) , also respectively generating five cores, Core B1, Core B2, Core B3, Core B4, and Core B5 to replace Core B.