Using CCOC(=O)c1cn2c(n1)c(OCC)nc1cc(Br)c(Br)cc12 to produce O=C(O)c1cn2c(n1)c(=O)[nH]c1cc(Br)c(Br)cc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.