NC(=O)CCNS(=O)(=O)CCCN(C(=O)Nc1cnccc1CNC(=O)NCCc1ccn[nH]1)C1CCCCC1
Protein model x967: Sidechains of M49 and M165 have rotated to create a more open pocket. Sidechain of N142 also flipped providing different H-bond opportunities. Fragment expansion: Ligands based on extension of pyridyl fragment of x107 into pocket between M49 and M165 using position of benzyl group of x72 as an initial guide. Fragments found by searching REAL database, various sets aligned in Pharmit using x967 receptor model and x107 and x72 ligands to define pharmacophore features. Top set screened through SeeSAR and SeeSAR models also checked with CSM-lig. Cyclohexane linked to x107 pyridyl moiety by ureido group makes an excellent core scaffold. Elaborations from the pyridyl ring, ureido nitrogens and cyclohexyl ring system examined.
Bit of a monster, but continuing from my previous set looked at alternatives to the ethyl-hydroxy ureido substituent and further extension of the sulphonamide. Compound submitted here has low picomolar - nanomolar affinity prediction in SeeSAR and picomolar affinity prediction in CSM-lig (score 9.3).