Using Cc1csc(Nc2ncc(Br)cc2O)n1, CC(C)(C)OC(=O)N1CCC(Br)C1 to produce Cc1csc(Nc2ncc(Br)cc2OC2CCN(C(=O)OC(C)(C)C)C2)n1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.