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 a anti histamine.
user
CNCC1(OC(=O)C(=O)OC2(CNC)CCN(C3CCCCC3)CC2)CCN(C2CCCCC2)CC1
assistant