trans-4-(Trifluoromethyl)cinnamic acid is a photosensitizing compound. It is used as a reagent in the synthesis of various compounds, such as heterocyclic compounds and pharmaceuticals. It has also been used as a catalyst for organic reactions such as the Heck reaction and the Suzuki-Miyaura reaction. It is also used as a fluorescent probe in biological studies to detect and monitor various biomolecules.

trans-Cinnamic acid (Myricitrine) exerts anti-diabetic activity by improving glucose tolerance in vivo and by stimulating insulin secretion in vitro.

(E)-3,4,5-Trimethoxycinnamic acid (O-Methylsinapic acid) is a natural product from the roots and rhizomes of Notopterygium incisum.

Piperonylic acid (2H-1,3-benzodioxole-5-carboxylic acid) is a natural molecule bearing a methylenedioxy function that closely mimics the structure of trans-cinnamic acid. Piperonylic acid selectively inactivate the CYP73A P450 subpopulation.

1. trans-Cinnamaldehyde (Phenylacrolein) exhibits excellent anti-inflammatory activities and antidepressant-like effects in stressed mid-aged rats as a COX-2 inhibitor. 2. Cinnamic aldehyde induces apoptosis of CML cells in vitro, down-regulation of the expression and function of BCR-ABL may be one of its most important anti-leukemia mechanisms. 3. Cinnamic aldehyde and cinnamic acid are cardioprotective in a rat model of ischemic myocardial injury, the mechanism is related to anti-oxidative and anti-inflammatory properties.