3-Phenylpropionic acid (hydrocinnamic acid, HA) is an end-product of the bacterial degradation of unabsorbed phenylalanine in the intestinal lumen. HA is used in ice cream, drinks, and candy manufacture field as a flavoring agent. In recent years, HA is widely used in the pharmaceutical industry. Hydrocinnamic Acid inhibits the currents of WT and SQT3 syndrome-related mutants of Kir2.1 channel.

2,6-Pyridinedicarboxylic acid (PDC, Dipicolinic acid) is a major component of bacterial endospores, comprising 5-15% of the spore dry weight, and is important for spore stability and resistance properties. 2,6-Pyridinedicarboxylic acid and its derivatives are introduced as a new sensitizer system for enzyme-amplified lanthanide luminescence (EALL), a detection scheme for bioassays, which combines enzymatic amplification with time-resolved luminescence measurements of lanthanide chelates.