2-hydroxy-4H-1,4-benzoxazin-3-one

2-hydroxy-4H-[1,4]benzoxazin-3-one

2-hydroxy-2H-1,4-benzoxazin-3(4H)-one

2-Hydroxy-3,4-dihydro-2H-1,4-benzoxazine-3-one

2-Hydroxy-2,3-dihydro-4H-1,4-benzoxazine-3-one