Using C[C@]12CC[C@H]3[C@@H](CCC4=CC(=O)[C@H]5CC5[C@@]43C)[C@@H]1CCC2=O, O=C1CCC(=O)N1Br to produce C[C@]12CC[C@H]3[C@@H](C[C@@H](Br)C4=CC(=O)[C@H]5CC5[C@@]43C)[C@@H]1CCC2=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.