Using CC(C)(C)OC(=O)CN, CCOC(=O)C1CCC(C=O)N1C(=O)OC(C)(C)C to produce CCOC(=O)C1CCC(CNCC(=O)OC(C)(C)C)N1C(=O)OC(C)(C)C, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.