4-(5-hydroxy-6-methyl-2-oxo-4H-pyrido[3,4-d][1,3]oxazin-1-ylmethyl)-benzonitrile 、
对氰基溴化苄 以gave 4-[5-(4-cyano-benzyloxy)-6-methyl-2-oxo-4H-pyrido[3,4-d][1,3]oxazin-1ylmethyl]-benzonitrile (83) (1.0 g, 84% yield) as a colorless solid的产率得到4-[5-(4-cyano-benzyloxy)-6-methyl-2-oxo-4H-pyrido[3,4-d][1,3]oxazin-1ylmethyl]-benzonitrile