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 nmda antagonist.
user
CC(=O)OC1c2cc(-c3ccccc3)cnc2C=Cc2c(C#N)cccc21
assistant