Using C1CCOC1, CCOC(=O)c1[nH]c(C)c(CCC(=O)O)c1C to produce CCOC(=O)c1[nH]c(C=O)c(CCC(=O)O)c1C, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.