Using O=C1Nc2ccc([N+](=O)[O-])cc2C1=O, COC(=O)CBr to produce COC(=O)CN1C(=O)C(=O)c2cc([N+](=O)[O-])ccc21, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.