Protocatechuic acid

Protocatechuic acid
Names
	Preferred IUPAC name 3,4-Dihydroxybenzoic acid
	Other names 3,4-Dihydroxybenzoic acid; PCA; Protocatechuate
Identifiers
CAS Number	99-50-3 ;
3D model (JSmol)	Interactive image;
3DMet	B00064;
ChEBI	CHEBI:36062 ;
ChEMBL	ChEMBL37537 ;
ChemSpider	71 ;
DrugBank	DB03946 ;
ECHA InfoCard	100.002.509
EC Number	202-760-0;
KEGG	C00230;
PubChem CID	72;
RTECS number	UL0560000;
UNII	36R5QJ8L4B ;
CompTox Dashboard (EPA)	DTXSID4021212 ;
	InChI InChI=1S/C7H6O4/c8-5-2-1-4(7(10)11)3-6(5)9/h1-3,8-9H,(H,10,11) Key: YQUVCSBJEUQKSH-UHFFFAOYSA-N ;
	SMILES C1=CC(=C(C=C1C(=O)O)O)O;
Properties
Chemical formula	C7H6O4
Molar mass	154.12 g/mol
Appearance	light brown solid
Density	1.524 g/cm3 (4 °C)
Melting point	202 °C (396 °F; 475 K)
Solubility in water	18 g/L (14 °C); 271 g/L (80 °C)
Solubility	soluble in ethanol, ether ; insoluble in benzene
Acidity (pKa)	4.48, 8.83, 12.6
Hazards
NFPA 704 (fire diamond)	2 0 0
Safety data sheet (SDS)	MSDS
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid. It is a major metabolite of antioxidant polyphenols found in green tea. It has mixed effects on normal and cancer cells in in vitro and in vivo studies.^[4]

^ ^a ^b Haynes, p. 3.190
^ Haynes, p. 5.148
^ Haynes, p. 5.91
^ Lin, H.-H.; Chen, J.-H.; Huang, C.-C.; Wang, C.-J. (June 2007). "Apoptotic effect of 3,4-dihydroxybenzoic acid on human gastric carcinoma cells involving JNK/p38 MAPK signaling activation". International Journal of Cancer. 120 (11): 2306–2316. doi:10.1002/ijc.22571. PMID 17304508.

[crc-1] Haynes, p. 3.190

[2] Haynes, p. 5.148

[3] Haynes, p. 5.91

[4] Lin, H.-H.; Chen, J.-H.; Huang, C.-C.; Wang, C.-J. (June 2007). "Apoptotic effect of 3,4-dihydroxybenzoic acid on human gastric carcinoma cells involving JNK/p38 MAPK signaling activation". International Journal of Cancer. 120 (11): 2306–2316. doi:10.1002/ijc.22571. PMID 17304508.

[1]

[2]

[3]

[4]

Names


Preferred IUPAC name 3,4-Dihydroxybenzoic acid
Other names 3,4-Dihydroxybenzoic acid PCA Protocatechuate
Identifiers
CAS Number	99-50-3^Y
3D model (JSmol)	Interactive image
3DMet	B00064
ChEBI	CHEBI:36062^Y
ChEMBL	ChEMBL37537^Y
ChemSpider	71^Y
DrugBank	DB03946^Y
ECHA InfoCard	100.002.509
EC Number	202-760-0
KEGG	C00230
PubChem CID	72
RTECS number	UL0560000
UNII	36R5QJ8L4B^Y
CompTox Dashboard (EPA)	DTXSID4021212
InChI InChI=1S/C7H6O4/c8-5-2-1-4(7(10)11)3-6(5)9/h1-3,8-9H,(H,10,11)^Y Key: YQUVCSBJEUQKSH-UHFFFAOYSA-N^Y
SMILES C1=CC(=C(C=C1C(=O)O)O)O
Properties
Chemical formula	C₇H₆O₄
Molar mass	154.12 g/mol
Appearance	light brown solid
Density	1.524 g/cm³ (4 °C)^[1]
Melting point	202 °C (396 °F; 475 K)^[1]
Solubility in water	18 g/L (14 °C) 271 g/L (80 °C)^[2]
Solubility	soluble in ethanol, ether insoluble in benzene
Acidity (pK_a)	4.48, 8.83, 12.6^[3]
Hazards
NFPA 704 (fire diamond)	2 0 0
Safety data sheet (SDS)	MSDS
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