Using Cc1c(C)c2c(c(C)c1O)SC(CCCC(C)(C)C(=O)O)O2 to produce Cc1c(C)c2c(c(C)c1O)SC(CCCC(C)(C)CO)O2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.