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
Given the following product, please provide possible reactants. <molecule_2d>
user
Possible reactant(s): COc1ccc(C2=C(c3cn(CCCO)c4ccccc34)C(=O)NC2=O)c2occc12 .
assistant