Using O=C1CCC(=O)N1Br, Cc1c(Cl)cccc1Cn1c(C)nc(=O)c2sc(N3CCOCC3)nc21 to produce Cc1c(Cl)cccc1Cn1c(CBr)nc(=O)c2sc(N3CCOCC3)nc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.