Using COc1c(F)c(F)c(C(=O)c2c(F)c(F)c(F)c(F)c2F)c(OC)c1F to produce O=C(c1c(O)c(F)c(O)c(F)c1F)c1c(F)c(F)c(F)c(F)c1F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.