Using CCC(CC)Oc1nc(C)nc(Nc2c(C)cc(C)cc2C)c1Br, O=C=O to produce CCC(CC)Oc1nc(C)nc(Nc2c(C)cc(C)cc2C)c1C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.