Using COB(OC)OC, Brc1ccc2sc3ccc(-n4c5ccccc5c5ccccc54)cc3c2c1 to produce OB(O)c1ccc2sc3ccc(-n4c5ccccc5c5ccccc54)cc3c2c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.