Benzoxazole is an aromatic organic compound with a molecular formula C7H5NO, a benzene-fused oxazole ring structure, and an odor similar to pyridine. Although benzoxazole itself is of little practical value, many derivatives of benzoxazoles are commercially important.
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||119.123 g·mol−1|
|Appearance||White to light yellow solid|
|Melting point||27 to 30 °C (81 to 86 °F; 300 to 303 K)|
|Boiling point||182 °C (360 °F; 455 K)|
|Flash point||58 °C (136 °F; 331 K)|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Being a heterocyclic compound, benzoxazole finds use in research as a starting material for the synthesis of larger, usually bioactive structures. Its aromaticity makes it relatively stable, although as a heterocycle, it has reactive sites which allow for functionalization.
Occurrence and applications
It is found within the chemical structures of pharmaceutical drugs such as flunoxaprofen and tafamidis. Benzoxazole derivatives are also of interest for optical brighteners in laundry detergents. Benzoxazoles belong to the group of well-known antifungal agents with antioxidant, antiallergic, antitumoral and antiparasitic activity.
- Structural isomers
- Anthranil, an analog with the oxygen atom in position 2
- Benzisoxazole, an analog with the nitrogen atom in position 2
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- E. Smulders, E. Sung "Laundry Detergents, 2. Ingredients and Products" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2012. doi:10.1002/14356007.o15_013
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