Using COC(=O)C1CCN(CC(=O)N2CCN(c3ccc(-c4ncccn4)cc3)CC2)C1 to produce O=C(O)C1CCN(CC(=O)N2CCN(c3ccc(-c4ncccn4)cc3)CC2)C1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.