Using CCOCc1nc2c(N)nc3cc(Br)cnc3c2n1CC(C)(C)NC(=O)OC(C)(C)C to produce CCOCc1nc2c(N)nc3cc(Br)cnc3c2n1CC(C)(C)N, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.