Using CCCCn1c(=O)oc(=O)c2cccnc21, CCOC(=O)CC(=O)OCC to produce CCCCn1c(=O)c(C(=O)OCC)c(O)c2cccnc21, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.