Oxazolone is a chemical compound and

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 ...

, with the molecular formula C₃H₃NO₂. It was named in-line with the

Hantzsch–Widman nomenclature In organic chemistry, Hantzsch–Widman nomenclature, also called the extended Hantzsch–Widman system (named for Arthur Rudolf Hantzsch and ), is a type of systematic chemical nomenclature used for naming heterocyclic parent hydrides having no ...

and is part of a large family of

oxazole Oxazole is the parent compound for a vast class of heterocyclic aromatic organic compounds. These are azoles with an oxygen and a nitrogen separated by one carbon. Oxazoles are aromatic compounds but less so than the thiazoles. Oxazole is a weak ...

based compounds. There are a total of 5

structural isomer In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a chemical compound, compound is another compound whose molecule has the same number of atoms of each element, but with logically distinct chemical bond, b ...

s of oxazolone; 3 according to the location of the carbonyl group and 2 more according to the location of the double bound C=X (with X= N or C): *2-(3''H'')oxazolone *2-(5''H'')oxazolone *4-(5''H'')-oxazolone *5-(2''H'')-oxazolone *5-(4''H'')-oxazolone Oxazolones

The 4-oxazolone motif, which is also formally a

lactam A lactam is a cyclic amide, formally derived from an amino alkanoic acid. The term is a portmanteau of the words ''lactone'' + ''amide''. Nomenclature Greek prefixes in alphabetical order indicate ring size: * α-Lactam (3-atom rings) * β-Lacta ...

, is present in a number of drugs ( fenozolone,

thozalinone Thozalinone (USAN) (brand name Stimsen; former developmental code name CL-39808) is a psychostimulant that has been used as an antidepressant in Europe. It has also been trialed as an anorectic. Thozalinone is described as a " dopaminergic sti ...

, cyclazodone,

reclazepam Reclazepam is a drug which is a benzodiazepine derivative. It has sedative and anxiolytic effects similar to those produced by other benzodiazepine derivatives, and has a short duration of action. Synthesis The reduction of the lactam in Delo ...

etc.). Substituted 5-oxazolones may also be regarded as the cyclization products of ''N''- acyl α-

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

s, making them lactones, and are sometimes referred to as azlactones.

References

{{reflist Oxazolones

See also

References