Using O=C1CCC(=O)N1Br, CC(C)(C)OC(=O)N[C@@H](CCCO)C(=O)OC1CCCC1 to produce CC(C)(C)OC(=O)N[C@@H](CCCBr)C(=O)OC1CCCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.