Using CC(C)(C)[Si](C)(C)OC[C@H]1O[C@@H](n2c(NCCc3ccc(-c4cccc(OCc5ccccc5)c4)cc3)nc3c(N)ncnc32)[C@H](O[Si](C)(C)C(C)(C)C)[C@@H]1O[Si](C)(C)C(C)(C)C, ClCCCBr to produce CC(C)(C)[Si](C)(C)OC[C@H]1O[C@@H](n2c(NCCc3ccc(-c4cccc(OCCCCl)c4)cc3)nc3c(N)ncnc32)[C@H](O[Si](C)(C)C(C)(C)C)[C@@H]1O[Si](C)(C)C(C)(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.