Using CCCc1c(OCC(O)CSCC2COC3(CCC(CC(=O)OCC)C3)S2)ccc(C(C)=O)c1O to produce CCCc1c(OCC(O)CSCC2COC3(CCC(CC(=O)O)C3)S2)ccc(C(C)=O)c1O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.