Benzothiazole, or more specifically1,3-benzothiazole, is anaromaticheterocyclic compound with the chemical formulaC 7H 5NS. It is colorless, slightly viscous liquid. Although the parent compound, benzothiazole is not widely used, many of its derivatives are found in commercial products or in nature.Firefly luciferin can be considered a derivative of benzothiazole.[1] It has a sulfurousodor and meaty flavor.[2]
The threestructural isomers of benzothizaole are 1,3-benzothiazole, 1,2-benzothiazole and 2,1-benzothiazole.
Benzothiazoles consist of a 5-membered 1,3-thiazole ringfused to a benzene ring. The nine atoms of the bicycle and the attached substituents are coplanar. The heterocyclic core of the molecule is readily substituted at themethyne (CH) centre in the thiazole ring. Thiazole is electron-withdrawing.
Many other precursors have been used, commonly aldehydes in the presence of oxidants.In some cases, benzothiazoles are prepared directly fromanilines, a process that entails ortho functionalization.[5]
Naturally occurring benzothiazoles are proposed to arise by condensation ofcysteine withquinones.[1]
Benzothiazole occurs naturally in some foods but is also used as afood additive.[1] It has a sulfurousodor and meaty flavor.[7] TheEuropean Food Safety Authority assessment had "no safety concern at estimated levels of intake as a flavouring substance".[8]
Benzothiazoles are widely used in thevulcanization of rubber, so their possible role in the environment has attracted attention. Evidence suggests that theybiodegrade readily.[17]
^abcLe Bozec, Lucille; Moody, Christopher J. (2009). "Naturally Occurring Nitrogen–Sulfur Compounds. The Benzothiazole Alkaloids".Australian Journal of Chemistry.62 (7): 639.doi:10.1071/CH09126.
^Gill, Rupinder K.; Rawal, Ravindra K.; Bariwal, Jitender (2015). "Recent Advances in the Chemistry and Biology of Benzothiazoles".Archiv der Pharmazie.348 (3):155–178.doi:10.1002/ardp.201400340.PMID25682746.
^T. E. Gilchrist "Heterocyclic Chemistry" 3rd Edition, Longman, 1992.
^Würfel, Hendryk; Jakobi, Dörthe (2018). "Syntheses of Substituted 2-Cyano-benzothiazoles".Organic Syntheses.95:177–191.doi:10.15227/orgsyn.095.0177.
^Keri, Rangappa S.; Patil, Mahadeo R.; Patil, Siddappa A.; Budagumpi, Srinivasa (2015). "A comprehensive review in current developments of benzothiazole-based molecules in medicinal chemistry".European Journal of Medicinal Chemistry.89:207–251.doi:10.1016/j.ejmech.2014.10.059.PMID25462241.
^Clarke, Bradley O.; Smith, Stephen R. (2011). "Review of 'emerging' organic contaminants in biosolids and assessment of international research priorities for the agricultural use of biosolids".Environment International.37 (1):226–247.Bibcode:2011EnInt..37..226C.doi:10.1016/j.envint.2010.06.004.PMID20797791.
