Pamoic acid explained

Pamoic acid, also called embonic acid, is a 2-Naphthoic acid derivative. Salts and esters of pamoic acid are known as pamoates or embonates. It can be prepared by the reaction of 3-hydroxy-2-naphthoic acid with formaldehyde.

In pharmacology, the salt form of pamoic acid (pamoate ion) can be used as a counterion of a drug compound to affect the dissolution rate of the drug.^[1] The presence of multiple oxygen atoms enables significant hydrogen bonding to occur. Hydrogen bonds facilitate the dissolution of compounds in water. Pharmaceutical drugs formulated this way include cycloguanil pamoate, hydroxyzine pamoate, imipramine pamoate, olanzapine pamoate hydrate, oxantel pamoate, pyrantel pamoate, and pyrvinium pamoate.

Pamoic acid has agonist activity for the orphan G protein-coupled receptor GPR35 by which it activates ERK and beta-arrestin2, and causes antinociceptive activity.^{[2] [3]}

Notes and References

1. 2102266 . 1990 . Saesmaa . T . Tötterman . AM . Dissolution studies on ampicillin embonate and amoxycillin embonate . 8 . 1 . 61–5 . Journal of Pharmaceutical and Biomedical Analysis . 10.1016/0731-7085(90)80007-c.
2. 10.1124/mol.110.066746 . Targeting of the Orphan Receptor GPR35 by Pamoic Acid: A Potent Activator of Extracellular Signal-Regulated Kinase and -Arrestin2 with Antinociceptive Activity . 2010 . Zhao . P. . Sharir . H. . Kapur . A. . Cowan . A. . Geller . E. B. . Adler . M. W. . Seltzman . H. H. . Reggio . P. H. . Heynen-Genel . S. . Sauer . M. . Chung . T. D. Y. . Bai . Y. . Chen . W. . Caron . M. G. . Barak . L. S. . Abood . M. E. . Molecular Pharmacology . 78 . 4 . 560–8 . 20826425 . 2981393. 8 .
3. Neubig, Richard R . Mind your salts: when the inactive constituent isn't . Molecular Pharmacology . 2010 . 78 . 4 . 558–9 . 10.1124/mol.110.067645 . 20651116. 1859819 .