Using CC(C)(C)OC(=O)N1CCC(=O)C(C)(C)C1, NCC[C@H](NC(=O)OCc1ccccc1)C(=O)O to produce CC(C)(C)OC(=O)N1CCC(NCC[C@H](NC(=O)OCc2ccccc2)C(=O)O)C(C)(C)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.