Using O=C(O)CN1CCN(CCN2CCNCC2)CCN(CC(=O)O)CC1, O=C(O)CBr to produce O=C(O)CN1CCN(CCN2CCN(CC(=O)O)CCN(CC(=O)O)CC2)CC1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.