Acetylformoin

Structural formula
General
Surname	Acetylformoin
other names	trans -3,4-dihydroxy-3-hexene-2,5-dione DHHD (open chain) 2,4-dihydroxy-2,5-dimethyl-oxacyclopent-4-en 2,4-dihydroxy-2,5-dimethyl-3 ( H ) -furanone (hemiacetal) Diacetylformoin
Molecular formula	C 6 H 8 O 4
Brief description	Intense caramel-like smelling solid with a bitter taste
External identifiers / databases
CAS number 10153-61-4 PubChem 45085737 ChemSpider 23253504 Wikidata Q1529271
properties
Molar mass	144.13 g mol −1
Physical state	firmly
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Acetylformoin is a very reactive breakdown product of carbohydrates ( hexoses ) such as glucose . The substance is a diketo-enediol ( reductone ) with six carbon atoms, which z. B. arises as an intermediate product in the Maillard reaction and smells intensely of caramel .

presentation

The processes involved in the Maillard reaction are very complex and lead to melanoidins at sufficiently high temperatures , with acetylformoin being formed as a reactive intermediate. Formally, acetylformoin is formed by splitting off two water molecules from glucose via so-called deoxyosones :

When disaccharides react , structurally very similar, substituted derivatives of acetylformoin are formed.

properties

Acetylformoin can occur both in an open-chain form and, like the carbohydrates, in a cyclic "furenose" - hemiacetal form. The compound is very reactive and forms melanoidins such as pronyl-lysine during the further Maillard reaction with amino acids or proteins . More generally, aminohexose reductones or glycosylamines are formed . Acetylformoin itself has a bitter taste. The open-chain form has an intense smell of caramel, whereas the cyclic ketal form is odorless. In protic solvents such as water, the ring-shaped, non-odorous shape is formed immediately.

See also

• Furanosis

Individual evidence

1. ↑ ^{a b} Wolfgang Engel: Odor-active compounds from the Maillard reaction of sulfur-free and sulfur-containing amine components with fructose ( Memento from September 28, 2007 in the Internet Archive ), German Research Institute for Food Chemistry , 1999.
2. ↑ ^{a b} Kirsten Zeiter: New Methods for the Synthesis of Conformationally Restricted Peptidomimetics , September 11, 2001, Ludwig Maximilians University Munich .
3. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
4. ↑ ^{a b c} Anke Hollnagel: Contributions to the chemistry of non-enzymatic browning of oligomeric carbohydrates , TU Berlin , April 19, 2000 (PDF; 818 kB).
5. ↑ Wolfgang Legrum: Fragrances, between stench and fragrance . Springer Fachmedien, Wiesbaden 2015, ISBN 978-3-658-07309-1 , p. 117 , doi : 10.1007 / 978-3-658-07310-7_5 .
6. ^ German Research Institute for Food Chemistry : Annual Report ( Memento of September 28, 2007 in the Internet Archive ), 2001.