Using Nc1c(Br)cc(O)c2c1C(=O)c1ccccc1C2=O, Nc1c(Oc2ccccc2)cc(O)c2c1C(=O)c1ccccc1C2=O to produce O=C1c2ccccc2C(=O)c2c(Oc3ccccc3)cccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.