Using C=CCC(C)(C)COC(=O)N[C@H](C(=O)N1C[C@H](Oc2nccc3cc(OC)c(Br)cc23)C[C@H]1C(=O)OCC)C1CCCCC1, CCCCC([Sn])=C(CCCC)CCCC to produce C=CCC(C)(C)COC(=O)N[C@H](C(=O)N1C[C@H](Oc2nccc3cc(OC)c(C=C)cc23)C[C@H]1C(=O)OCC)C1CCCCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.