Using CC(C)n1c(=O)n(-c2ccc3c(c2)CCN3C(=O)OC(C)(C)C)c2ncccc21 to produce CC(C)n1c(=O)n(-c2ccc3c(c2)CCN3)c2ncccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.