Using CCOc1cc(Cc2cnc(N)nc2N)cc(OCC)c1Br, O=C([O-])[O-] to produce CCOc1cc(Cc2cnc(N)nc2N)cc(OCC)c1-c1cccc(OC)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.