Using Cc1ccsc1-c1ccc(-c2ccc(-c3sc(C=O)cc3C)s2)s1 to produce Cc1ccsc1-c1ccc(-c2ccc(-c3sc(CO)cc3C)s2)s1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.