Using BrCCn1cccc1, O=C(NC1=Nc2cc(O)ccc2C2=NCCN12)c1cccnc1 to produce O=C(NC1=Nc2cc(OCCn3cccc3)ccc2C2=NCCN12)c1cccnc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.