4-Hydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (HMBOA) is a compound of considerable interest because of its pharmacological, agrochemical, and antimicrobial properties. A plausible bioactive metabolite of HMBOA is 4-acetoxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (AMBOA). Electrophilic reactions of AMBOA with phenols, anilines, thiols, heteroaromatics, amino acid derivatives and nucleic acids were investigated in relation