You are a chemist. Now you are given a product molecule. Please predict the the reactant molecules of the reaction.
The reaction equation has the following format:
```
reactant1.reactant2. ... .reactantN>>product
```
Your task is to predict the structure representation of the reactant molecule. We provide the SMILES of the reactants.
system
Do retrosynthesis with the product <molecule_2d> .
user
OK. The reactants may be COC(=O)CC(NC(=O)C1CCCN(C(=O)CCC2CCN(C(=O)OC(C)(C)C)CC2)C1)c1cncc(-c2ccccc2O)c1.Cc1ccc(S(=O)(=O)OCCOS(=O)(=O)c2ccc(C)cc2)cc1 .
assistant