Biomimetic synthesis of 4‐acetylbenzoxazolin‐2(3H)‐one isolated from Zea mays

Abstract 4‐Acetylbenzoxazolin‐2(3H)‐one has been prepared biomimetically during attempts to synthesize the hemiacetalic hydroxamic acid 5‐acetyl‐2,4‐dihydroxy‐2H‐1,4‐benzoxazin‐3(4H)‐one by the immediate degradation of this unstable compound generated as an intermediate. Thus, 4‐acetylbenzoxazolin‐2(3H)‐one recently isolated from Zea mays kernels, and similar to other benzoxazolin‐2(3H)‐ones known from plant sources, is assumed to have originated from the degradation of natural 5‐acetyl‐2,4‐dihydroxy‐2H‐1,4‐benzoxazin‐3(4H)‐one which in turn could have been enzymatically released by a β‐glucosidase from the corresponding 2‐β‐D‐glucoside.