Using CC(Br)Br, COC(=O)c1c(C)oc2cc(Oc3ccnc4cc(O)ccc34)ccc12 to produce COC(=O)c1c(C)oc2cc(Oc3ccnc4cc(OCCBr)ccc34)ccc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.