Using C[C@@]12C[C@@H]3CC[C@@H]4CC(=O)CC[C@@H]4[C@H]3C[C@H]1CC[C@H]2O to produce C[C@@]12C[C@@H]3CC[C@@H]4CC(=O)CC[C@@H]4[C@H]3C[C@H]1CCC2=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.