Pyrazolones on:
[Wikipedia]
[Google]
[Amazon]
Pyrazolone is 5-membered heterocycle containing two adjacent nitrogen atoms. It can be viewed as a derivative of pyrazole possessing an additional carbonyl (C=O) group. Compounds containing this functional group are useful commercially in analgesics and dyes.
The first synthesis of pyrazolones was reported in 1883 by Ludwig Knorr, via a condensation reaction between ethyl acetoacetate and phenylhydrazine.
:
Many pyrazolones are produced by functionalization of preformed pyrazolones.
Pyrazolones are amongst the oldest synthetic pharmaceuticals, starting with the introduction of antipyrine (phenazone) in 1880s. The compounds generally act as analgesics and include dipyrone (Metamizole), aminophenazone,
Pubchem - 3-Pyrazolone
Pubchem - 4-Pyrazolone
{{Authority control
Structure and synthesis
Pyrazolone can exist in two isomers: 3-pyrazolone and 4-pyrazolone. These isomers can interconvert via lactam–lactim and imine–enamine tautomerism; these conversion often display photochromism. For pyrazolone derivatives, the 3-pyrazolone isomer can be stabilized with ''N''-alkyl or ''N''-aryl substituents. :
The first synthesis of pyrazolones was reported in 1883 by Ludwig Knorr, via a condensation reaction between ethyl acetoacetate and phenylhydrazine.
:
Many pyrazolones are produced by functionalization of preformed pyrazolones.
Applications
Pharmaceuticals
Pyrazolones are amongst the oldest synthetic pharmaceuticals, starting with the introduction of antipyrine (phenazone) in 1880s. The compounds generally act as analgesics and include dipyrone (Metamizole), aminophenazone, ampyrone
Ampyrone is a metabolite of aminopyrine with analgesic, anti-inflammatory, and antipyretic properties. Its use as a drug is discouraged due to the risk of agranulocytosis. It is used as a reagent for biochemical reactions producing peroxides ...
, famprofazone
Famprofazone (Gewodin, Gewolen) is a nonsteroidal anti-inflammatory agent (NSAID) of the pyrazolone series which is available over-the-counter in some countries such as Taiwan. It has analgesic, anti-inflammatory, and antipyretic effects. Famprof ...
, morazone, nifenazone
Nifenazone is a drug that has been used as an analgesic for a number of rheumatic conditions.
See also
* Aminopyrine
Aminophenazone (or aminopyrine, amidopyrine, Pyramidon) is a non-narcotic analgesic substance. It is a pyrazolone and a der ...
, piperylon
Piperylone is a pyrazolone with analgesic, anti-inflammatory, and antipyretic properties.
References
Pyrazolones
Analgesics
Antipyretics
Nonsteroidal anti-inflammatory drugs
{{analgesic-stub ...
and propyphenazone. Of these dipyrone is perhaps the most widely used.
The basic structure has been also used in a number of newer drugs of other effects. Edaravone
Edaravone, sold under the brand name Radicava among others, is a medication used to treat stroke and amyotrophic lateral sclerosis (ALS). It is given by intravenous infusion and Oral administration, by mouth.
The most common side effects includ ...
is useful for prevention and/or therapy of arterial wall injury. Eltrombopag is used to address low blood platelet count.
Dyes
Pyrazolone groups are present in several important dyes. They are commonly used in combination with azo groups to give a sub-family of azo dyes; sometimes referred to as azopyrazolones ( tartrazine,orange B
Orange B is a food dye from the azo dye group. It is approved by the United States Food and Drug Administration (FDA) for use only in hot dog and sausage
A sausage is a type of meat product usually made from ground meat—often pork, b ...
, mordant red 19, yellow 2G
Yellow 2G is a food coloring denoted by E number E107 with the Colour Index CI18965. It has the appearance of a yellow powder, and it is soluble in water. It is a synthetic yellow azo dye.
It is not listed by the UK's Food Standards Agency amon ...
). Acid Yellow 17
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...
, Acid Yellow 23
Tartrazine is a synthetic lemon yellow azo dye primarily used as a food coloring. It is also known as E number E102, C.I. 19140, FD&C Yellow 5, Yellow 5 Lake, Acid Yellow 23, Food Yellow 4, and trisodium 1-(4-sulfonatophenyl)-4-(4-sulfonatop ...
(tartrazine), Pigment Yellow 13
Pigment Yellow 13 is an organic compound and an azo compound. It is a widely used yellow pigment. It is also classified as a diarylide pigment, being derived from 3,3'-dichlorobenzidine. It is closely related to Pigment Yellow 12
Pigment Yello ...
, and Pigment Red 38
A pigment is a colored material that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compoun ...
are produced on the multi-ton scale annually.
Ligands
Pyrazolones have been studied as ligands.References
External links
*Pubchem - 3-Pyrazolone
Pubchem - 4-Pyrazolone
{{Authority control