Fumaric acid

Fumaric acid

Names
IUPAC name (E)-Butenedioic acid
Other names trans-1,2-Ethylenedicarboxylic acid 2-Butenedioic acid trans-butenedioic acid Allomaleic acid Boletic acid Donitic acid Lichenic acid
Identifiers
CAS Number	110-17-8 Y
ChEBI	CHEBI:18012 Y
ChEMBL	ChEMBL503160 Y
ChemSpider	10197150 Y
DrugBank	DB04299 Y
EC Number	203-743-0
Jmol 3D model	Interactive image
KEGG	C00122 Y
UNII	88XHZ13131 Y
InChI InChI=1S/C4H4O4/c5-3(6)1-2-4(7)8/h1-2H,(H,5,6)(H,7,8)/b2-1+ Y Key: VZCYOOQTPOCHFL-OWOJBTEDSA-N Y InChI=1/C4H4O4/c5-3(6)1-2-4(7)8/h1-2H,(H,5,6)(H,7,8)/b2-1+ Key: VZCYOOQTPOCHFL-OWOJBTEDBF
SMILES C(=C/C(=O)O)\C(=O)O
Properties
Chemical formula	C4H4O4
Molar mass	116.07 g·mol−1
Appearance	White solid
Density	1.635 g/cm3
Melting point	287 °C (549 °F; 560 K) (decomp)
Solubility in water	4.3 g/L at 20°C
Acidity (pKa)	pka1 = 3.03, pka2 = 4.44
Pharmacology
ATC code	D05AX01
Vapor pressure	{{{value}}}
Related compounds
Related carboxylic acids	maleic acid succinic acid crotonic acid
Related compounds	fumaryl chloride fumaronitrile dimethyl fumarate iron(II) fumarate
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

Fumaric acid or trans-butenedioic acid is the chemical compound with the formula HO₂CCH=CHCO₂H. This white crystalline compound is one of two isomeric unsaturated dicarboxylic acids, the other being maleic acid. In fumaric acid the carboxylic acid groups are trans (E) and in maleic acid they are cis (Z). Fumaric acid has a fruit-like taste. The salts and esters are known as fumarates.

Chemistry

Fumaric acid was first prepared from succinic acid. A traditional synthesis involves oxidation of furfural (from the processing of maize) using chlorate in the presence of a vanadium-based catalyst. Currently, industrial synthesis of fumaric acid is mostly based on catalytic isomerisation of maleic acid in aqueous solutions at low pH. Maleic acid is accessible in large volumes as a hydrolysis product of maleic anhydride, produced by catalytic oxidation of benzene or butane.

The chemical properties of fumaric acid can be anticipated from its component functional groups. This weak acid forms a diester, it undergoes additions across the double bond, and it is an excellent dienophile.

Fumaric acid does not combust in a bomb calorimeter under conditions where maleic acid deflagrates smoothly. For teaching experiments designed to measure the difference in energy between the cis- and trans- isomers, a measured quantity of carbon can be ground with the subject compound and the enthalpy of combustion computed by difference.

Biology

Fumaric acid is found in fumitory (Fumaria officinalis), bolete mushrooms (specifically Boletus fomentarius var. pseudo-igniarius), lichen, and Iceland moss.

Fumarate is an intermediate in the citric acid cycle used by cells to produce energy in the form of adenosine triphosphate (ATP) from food. It is formed by the oxidation of succinate by the enzyme succinate dehydrogenase. Fumarate is then converted by the enzyme fumarase to malate. Human skin naturally produces fumaric acid when exposed to sunlight.

Fumarate is also a product of the urea cycle.

Uses

Food

Fumaric acid has been used a food acidulant since 1946. It is approved for use as a food additive in the EU, USA and Australia and New Zealand. As a food additive, it is used as an acidity regulator and can be denoted by the E number E297. It is generally used in beverages and baking powders for which requirements are placed on purity. It is generally used as a substitute for tartaric acid and occasionally in place of citric acid, at a rate of 1 g of fumaric acid to every ~1.5 g of citric acid, in order to add sourness, similarly to the way malic acid is used. As well as being a component of some artificial vinegar flavors, such as "Salt and Vinegar" flavored potato chips, it is also used as a coagulant in stovetop pudding mixes.

Medicine

In patients with relapsing-remitting multiple sclerosis, dimethyl fumarate (BG-12, Biogen) significantly reduced relapse and disability progression in a phase 3 trial. It activates the Nrf2 antioxidant response pathway, the primary cellular defense against the cytotoxic effects of oxidative stress.

Other uses

Fumaric acid is used in the manufacture of polyester resins and polyhydric alcohols and as a mordant for dyes.

Safety

Fumaric acid converts to the irritant maleic anhydride, upon partial combustion.

It is "practically non-toxic" but high doses are probably nephrotoxic after long term use.

Interactive pathway map

Click on genes, proteins and metabolites below to link to respective articles.

[[File:

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

[[

]]

|{{{bSize}}}px|alt=TCA Cycle edit]]

File:TCACycle WP78.png

TCA Cycle edit

See also

• Dermatology
• Photosynthesis
• Maleic acid, the cis-isomer of fumaric acid

External links

• International Chemical Safety Card 1173