Using O=C1C(=O)c2ccc(Br)c3cccc1c23, O=C(Cc1ccccc1)Cc1ccccc1 to produce O=C1C(c2ccccc2)=C2C(=C1c1ccccc1)c1ccc(Br)c3cccc2c13, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.