C6H5C2H2C2H2CO2H

Cinnamic Cin*nam"ic, a. [From {Cinnamon}.] (Chem.) Pertaining to, or obtained from, cinnamon. [1913 Webster]

{Cinnamic acid} (Chem.), a white, crystalline, odorless substance. {C6H5.C2H2C2H2.CO2H}, formerly obtained from storax and oil of cinnamon, now made from certain benzene derivatives in large quantities, and used for the artificial production of indigo. [1913 Webster]