Using CCOC(=O)CN1C(=O)C(N2C(=O)c3ccccc3C2=O)CCCc2ccccc21 to produce CCOC(=O)CN1C(=O)C(N)CCCc2ccccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.