Using C=CCBr, CCCCOC1=C(O)C(=O)O[C@]1(CC(O)CO)[C@@H](O)CO to produce C=CCOC1=C(OCCCC)[C@@](CC(O)CO)([C@@H](O)CO)OC1=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.