You are a chemist. Now you are given a description of a molecule. Please generate a molecule that meets the description.
system
I give you a description of a molecule, and you need to return one molecule in SMILES that meets the description. The description: The molecule is anti tussive.
user
COc1ccc(C)c2c1OC1C(=O)CCC3(O)C(C)N(CC4CC4)CCC213
assistant