Pyrones or pyranones are a class of
heterocyclic
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and ...
chemical compounds. They contain an
unsaturated six-membered ring containing one oxygen atom and a
ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bo ...
functional group
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest ...
.
There are two isomers denoted as
2-pyrone and
4-pyrone
4-Pyrone (γ-pyrone or pyran-4-one) is an unsaturated cyclic chemical compound with the molecular formula C5H4O2. It is isomeric with 2-pyrone.
Preparation
4-Pyrone is prepared via the thermal decarboxylation of chelidonic acid.
Reactions
4- ...
. The 2-pyrone (or α-pyrone) structure is found in nature as part of the
coumarin
Coumarin () or 2''H''-chromen-2-one is an aromatic organic chemical compound with formula . Its molecule can be described as a benzene molecule with two adjacent hydrogen atoms replaced by a lactone-like chain , forming a second six-membered h ...
ring system. 4-Pyrone (or γ-pyrone) is found in some natural chemical compounds such as
chromone
Chromone (or 1,4-benzopyrone) is a derivative of benzopyran with a substituted keto group on the pyran ring. It is an isomer of coumarin.
Derivatives of chromone are collectively known as ''chromones''. Most, though not all, chromones are also ...
,
maltol
Maltol is a naturally occurring organic compound that is used primarily as a flavor enhancer. It is found in the bark of larch tree, in pine needles, and in roasted malt (from which it gets its name). It is a white crystalline powder that is ...
and
kojic acid
Kojic acid is a chelation agent produced by several species of fungi, especially ''Aspergillus oryzae'', which has the Japanese common name ''koji''. Kojic acid is a by-product in the fermentation process of malting rice, for use in the manufactur ...
.
See also
*
Furanone
2-Furanone is a heterocyclic organic compound. It is also known as γ-crotonolactone (GCL), as it is formally the lactone derived from γ-hydroxyisocrotonic acid. The chemical is colloquially called "butenolide", and is the parent structure for th ...
, which has one fewer carbon atom in the ring.
References
{{heterocyclic-stub