Using O=S([O-])O, CC(=O)c1cc2c(s1)SCCN(CCCCN1CCN(c3ncccn3)CC1)C2=O to produce CC(=O)c1cc2c(s1)S(=O)CCN(CCCCN1CCN(c3ncccn3)CC1)C2=O, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.