O=C(CC1(CC(=O)NC2CC2)C(=O)Nc2ccccc21)Nc1cccc(Cl)c1
CCNC(=O)CC1(CC(=O)Nc2cccc(Cl)c2)C(=O)Nc2ccccc21
CC(C)NC(=O)CC1(CC(=O)Nc2cccc(Cl)c2)C(=O)Nc2ccccc21
Same as previous
These can be synthetised more easily using symmetric diacid (or more preferably cyclic anhydride) intermediate