Benzoxazines are a group ofisomeric bicyclicheterocyclic chemical compounds that consist of abenzene ring fused to anoxazine ring.[1] The different isomers depend on the relative positions of the oxygen and nitrogen atoms in the oxazine ring, on the location of ring fusion, and on the position of thedouble bond in the oxazine ring.[1] They have the molecular formula C8H7NO.
1,3-Benzoxazines can be synthesized by theMannich reaction using aphenol, an amine, and formaldehyde.[2]
Benzoxazine rings form the central chemical structure of a number of pharmaceutical drugs including, for example,apararenone,[3]elbasvir,[4] andetifoxine.[5]
Polybenzoxazines, also called benzoxazine resins, are a class of polymers that are produced from thering-opening polymerization of 3-phenyl-2,4-dihydro-1,3-benzoxazine monomers and its chemicalderivatives.[6] The main applications of polybenzoxazines are as adhesives and in fiber-reinforced plastics.