Using COC(=O)CCCCCCCCCCS, CC(=O)OC[C@H]1O[C@H](OC[C@H]2O[C@H](O[C@H]3[C@H](OC(C)=O)[C@@H](OC(C)=O)[C@@H](O[C@H]4[C@H](OC(C)=O)[C@@H](OC(C)=O)[C@H](OCCBr)O[C@@H]4COC(C)=O)O[C@@H]3COC(C)=O)[C@H](OC(C)=O)[C@@H](OC(C)=O)[C@@H]2OC(C)=O)[C@H](OC(C)=O)[C@@H](OC(C)=O)[C@@H]1OC(C)=O to produce COC(=O)CCCCCCCCCCSCCO[C@@H]1O[C@H](COC(C)=O)[C@@H](O[C@H]2O[C@H](COC(C)=O)[C@@H](O[C@H]3O[C@H](CO[C@H]4O[C@H](COC(C)=O)[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]4OC(C)=O)[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]3OC(C)=O)[C@H](OC(C)=O)[C@H]2OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.