Using O=Cc1ccccc1, O=C(O)Cc1ccc2c(c1)C(=O)CC2 to produce O=C(O)Cc1ccc2c(c1)C(=O)C(=Cc1ccccc1)C2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.