You are a chemist. Now you are given a description of a molecule. Please generate a molecule that meets the description.
system
I need a molecule that meets the following conditions: The molecule has Unpleasant odor. Hazardous polymerization may occur. polymerization may be caused by elevated temperature or alkalies. uninhibited monomer vapor may form polymer in vents and other confined spaces. When heated to decomposition it emits toxic fumes of  nitrogen oxides and cyanides. Please represent the molecule in SMILES.
user
C=CC#N
assistant