Using O=CC1=C(Cl)c2sc3nc4n(c(=O)c3c2CC1)CCCCC4, C1CCOC1 to produce O=C(O)C1=C(Cl)c2sc3nc4n(c(=O)c3c2CC1)CCCCC4, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.