1,2-Dihydro-4H-3,1-benzoxazin-2-one 1,4-Dihydro-2H-3,1-benzoxazin-2-one 13213-88-2 4-27-00-02727 (Beilstein Handbook Reference) 4H-3,1-BENZOXAZIN-2-ONE, 1,2-DIHYDRO- BRN 0133061 EINECS 236-183-0