O=c1c(-c2cccnc2)c[nH]cc1-c1ccccn1
CCN(CC)C(=O)CC1CNCCN1Cc1ccccn1
CCc1cnc2[nH]cc(CCNC(=O)C3CCOCC3)c2c1
CCc1cnc2[nH]cc(CCNC(=O)c3ccccc3)c2c1
Fragments were grown until their binding affinity, estimated using SeeSAR, was in the nanomolar range. Only the structure for which the synthesis seems rapid were selected.