Pamoic acid
 | |
| Names | |
|---|---|
| Preferred IUPAC name
4,4'-Methylenebis(3-hydroxynaphthalene-2-carboxylic acid) | |
| Other names
4,4'-Methylenebis(3-hydroxy-2-naphthoic acid) Embonic acid | |
| Identifiers | |
130-85-8  | |
| 3D model (Jmol) | Interactive image Interactive image |
| 901319 | |
| ChEBI | CHEBI:50186 |
| ChEMBL | ChEMBL177880 |
| ChemSpider | 8228 |
| ECHA InfoCard | 100.004.545 |
| EC Number | 204-998-0 |
| 2920 | |
| MeSH | Pamoic+acid |
| PubChem | 8546 |
| RTECS number | QL2180000 |
| UNII | 7RRQ8QZ38N |
| |
| |
| Properties | |
| C23H16O6 | |
| Molar mass | 388.38 g·mol−1 |
| Melting point | ≥300 °C |
| log P | 6.169 |
| Acidity (pKa) | 2.675 |
| Hazards | |
| Main hazards | Causes skin irritation Causes serious eye irritation |
| EU classification (DSD) |
 Xi |
| R-phrases | R36/37/38 |
| S-phrases | S26 S36 |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Pamoic acid, also called embonic acid, is a naphthoic acid derivative. Salts and esters of pamoic acid are known as pamoates or embonates. It can be prepared by the reaction of 2-hydroxy-3-naphthoic acid with formaldehyde.
In pharmacology, the salt form of pamoic acid (pamoate ion) can be used as a counter ion of a drug compound to increase the solubility of the drug in water.[2] The presence of multiple oxygen atoms enables significant hydrogen bonding to occur. Hydrogen bonds facilitate the dissolution of compounds in water.
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.[3][4] Although (like other drug salts) it has been considered an inactive compound by the FDA, these recent data suggest that its permitted uses may need to be reexamined.
References
- ↑ Merck Index, 12th Edition, 7136.
- ↑ Saesmaa, T; Tötterman, AM (1990). "Dissolution studies on ampicillin embonate and amoxycillin embonate". Journal of pharmaceutical and biomedical analysis. 8 (1): 61–5. doi:10.1016/0731-7085(90)80007-c. PMID 2102266.
- ↑ Zhao, P.; Sharir, H.; Kapur, A.; Cowan, A.; Geller, E. B.; Adler, M. W.; Seltzman, H. H.; Reggio, P. H.; et al. (2010). "Targeting of the Orphan Receptor GPR35 by Pamoic Acid: A Potent Activator of Extracellular Signal-Regulated Kinase and -Arrestin2 with Antinociceptive Activity". Molecular Pharmacology. 78 (4): 560–8. doi:10.1124/mol.110.066746. PMC 2981393
. PMID 20826425. - ↑ Neubig, Richard R (2010). "Mind your salts: when the inactive constituent isn't". Molecular Pharmacology. 78 (4): 558–9. doi:10.1124/mol.110.067645. PMID 20651116.