Quinic acid

Quinic acid is a cyclitol, a cyclic polyol, and a cyclohexanecarboxylic acid. It is a colorless solid that can be extracted from plant sources. Quinic acid is implicated in the perceived acidity of coffee.

Quinic acid

Quinic acid Quinic acid
Names
Preferred IUPAC name (1S,3R,4S,5R)-1,3,4,5-Tetrahydroxycyclohexane-1-carboxylic acid
Identifiers
CAS Number	77-95-2 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:17521 Y
ChEMBL	ChEMBL465398 Y
ChemSpider	10246715 Y
PubChem CID	6508
UNII	058C04BGYI Y
InChI InChI=1S/C7H12O6/c8-3-1-7(13,6(11)12)2-4(9)5(3)10/h3-5,8-10,13H,1-2H2,(H,11,12)/t3-,4-,5-,7+/m1/s1 Y Key: AAWZDTNXLSGCEK-WYWMIBKRSA-N Y InChI=1/C7H12O6/c8-3-1-7(13,6(11)12)2-4(9)5(3)10/h3-5,8-10,13H,1-2H2,(H,11,12)/t3-,4-,5-,7+/m1/s1 Key: AAWZDTNXLSGCEK-WYWMIBKRBU
SMILES O[C@]1(C[C@@H](O)[C@@H](O)[C@H](O)C1)C(O)=O
Properties
Chemical formula	C7H12O6
Molar mass	192.17 g/mol
Density	1.35 g/cm3
Melting point	168 °C (334 °F; 441 K)
Hazards
NFPA 704 (fire diamond)	<imagemap> File:NFPA 704.svg|80px|alt=NFPA 704 four-colored diamond poly 150 150 300 300 150 450 0 300 Health 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g. sodium chloride poly 300 0 450 150 300 300 150 150 Flammability 0: Will not burn. E.g. water poly 450 150 600 300 450 450 300 300 Instability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogen poly 300 300 450 450 300 600 150 450 Special hazards (white): no code desc none </imagemap> 0 0 0
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Occurrence and preparation

The compound is obtained from cinchona bark, coffee beans, and the bark of Eucalyptus globulus. It is a constituent of the tara tannins.

Urtica dioica, the European stinging nettle, is another common source.

It is made synthetically by hydrolysis of chlorogenic acid. Quinic acid is also implicated in the perceived acidity of coffee.

History and biosynthesis

Shikimic acid, biosynthetic precursor to aromatic amino acids, is a close relative of quinic acid.

This substance was isolated for the first time in 1790 by German pharmacist Friedrich Christian Hofmann in Leer from Cinchona. Its transformation into hippuric acid by animal metabolism was studied by German chemist Eduard Lautemann in 1863.

Its biosynthesis begins with the transformation of glucose into erythrose 4-phosphate. This four-carbon substrate is condensed with phosphoenol pyruvate to give the seven-carbon 3-deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) by the action of a synthase. Two subsequent steps involving dehydroquinic acid synthase and a dehydrogenase afford the compound.

Derived bicyclic lactones are called quinides. One example is 4-caffeoyl-1,5-quinide.

Dehydrogenation and oxidation of quinic acid affords gallic acid.

Applications and medicinal activity

Quinic acid is used as an astringent.

This acid is a versatile chiral starting material for the synthesis of pharmaceuticals. It is a building block in the synthesis of Oseltamivir, which is used to treat influenza A and B.

Further reading

• "Quinic acid - chiral compounds from nature - Buchler quinine plant in Braunschweig, Germany". Quinic acid. Retrieved September 5, 2005.
• "Quinic acid". Fast Health. Retrieved September 5, 2005.
• "History of Xenobiotic Metabolism". Archived from the original on April 12, 2005. Retrieved September 5, 2005.
• Ripley, George; Dana, Charles A., eds. (1879). "Kinic Acid" . The American Cyclopædia.