Using COC(=O)c1cc(N)ccc1O, CC(C)(C)OC(=O)NCC(=O)O to produce COC(=O)c1cc(NC(=O)CNC(=O)OC(C)(C)C)ccc1O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.