Chlorogenic acid

Chlorogenic acid

Names
IUPAC name (1S,3R,4R,5R)-3-{[(2E)-3-(3,4-dihydroxyphenyl)prop-2-enoyl]oxy}-1,4,5-trihydroxycyclohexanecarboxylic acid
Other names 3-(3,4-Dihydroxycinnamoyl)quinate 3-(3,4-Dihydroxycinnamoyl)quinic acid 3-Caffeoylquinate 3-Caffeoylquinic acid 3-CQA 3-O-Caffeoylquinic acid Chlorogenate Chlorogenic acid Heriguard 3-trans-Caffeoylquinic acid
Identifiers
CAS Number	327-97-9 Y 202650-88-2 (E) N
3D model (Jmol)	Interactive image
ChEBI	CHEBI:16112 N
ChEMBL	ChEMBL284616 N
ChemSpider	1405788 Y
ECHA InfoCard	100.005.751
PubChem	1794427
RTECS number	GU8480000
UNII	318ADP12RI (E) N
InChI InChI=1S/C16H18O9/c17-9-3-1-8(5-10(9)18)2-4-13(20)25-12-7-16(24,15(22)23)6-11(19)14(12)21/h1-5,11-12,14,17-19,21,24H,6-7H2,(H,22,23)/b4-2+/t11-,12-,14-,16+/m1/s1 Y Key: CWVRJTMFETXNAD-JUHZACGLSA-N Y InChI=1/C16H18O9/c17-9-3-1-8(5-10(9)18)2-4-13(20)25-12-7-16(24,15(22)23)6-11(19)14(12)21/h1-5,11-12,14,17-19,21,24H,6-7H2,(H,22,23)/b4-2+/t11-,12-,14-,16+/m1/s1 Key: CWVRJTMFETXNAD-JUHZACGLBD
SMILES O=C(O)[C@]2(O)C[C@@H](O)[C@@H](O)[C@H](OC(=O)\C=C\c1ccc(O)c(O)c1)C2
Properties
Chemical formula	C16H18O9
Molar mass	354.31 g·mol−1
Density	1.28 g/cm3
Melting point	207 to 209 °C (405 to 408 °F; 480 to 482 K)
Hazards
Safety data sheet	External MSDS
R-phrases	-
S-phrases	S24 S25 S28 S37 S45
NFPA 704	0 1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Chlorogenic acid (CGA) is a natural chemical compound which is the ester of caffeic acid and (−)-quinic acid. It is an important biosynthetic intermediate. Chlorogenic acid is an important intermediate in lignin biosynthesis. This compound, known as an antioxidant, may also slow the release of glucose into the bloodstream after a meal.

The term chlorogenic acids can also refer to a related family of esters of hydroxycinnamic acids (caffeic acid, ferulic acid and p-coumaric acid) with quinic acid.

Despite the "chloro" of the name, chlorogenic acids contain no chlorine. Instead, the name comes from the Greek χλωρός (light green) and -γένος (a suffix meaning "giving rise to"), because of the green color produced when chlorogenic acids are oxidized.

Structurally, chlorogenic acid is the ester formed between caffeic acid and the 3-hydroxyl position of L-quinic acid. Isomers of chlorogenic acid include the caffeoyl ester at other hydroxyl sites on the quinic acid ring: 4-O-caffeoylquinic acid (cryptochlorogenic acid or 4-CQA) and 5-O-caffeoylquinic acid (neochlorogenic acid or 5-CQA). The epimer at position 1 has not yet been reported.

It should be noted that there is considerable ambiguity about the atom-numbering of chlorogenic acid. The order of numbering of atoms on the quinic acid ring was reversed in 1976 following IUPAC guidelines, with the consequence that 3-CQA became 5-CQA, and 5-CQA became 3-CQA. This article uses the original numbering, which was exclusive prior to 1976, (chlorogenic acid being 3-CQA, while neochlorogenic acid is 5-CQA). Thereafter researchers and manufacturers have been divided, with both numbering systems in use. Even the 1976 IUPAC recommendations are not entirely satisfactory when applied to some of the less common chlorogenic acids.