Using C#CCOC, CC(C)(C)OC(=O)N(C(=O)OC(C)(C)C)C1=NC2(CO1)c1cc(Br)ccc1OCC21COC1 to produce COCC#Cc1ccc2c(c1)C1(COC(N(C(=O)OC(C)(C)C)C(=O)OC(C)(C)C)=N1)C1(COC1)CO2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.