NOVELTY - Forming quinoxaline-N,N-dioxide compound involves adding concentrated hydrochloric acid and acetone in reaction bottle, adding saturated sodium nitrite, controlling temperature at 0-10 degrees C, adjusting pH with sodium hydroxide, recycling acetone, extracting with ethyl acetate, evaporating ethyl acetate, adding halogenated hydrocarbon and 2-furazan N-oxide and solvent, where solvent is e.g. DMF or acetonitrile, oxidizing, adding acetone oxime, adding alkali catalyst, reacting, washing by methanol, adding water and acetyl hydrazine, dripping concentrated sulfuric acid, heating and drying.    USE - For chemical synthesis of quinoxaline-N,N-dioxide compound (claimed) used as veterinary medicine; and as broad spectrum antibiotic for promoting growth in animals.    ADVANTAGE - The method is simple, and has optimization of reaction conditions. The method has simple steps and provides high yield of compound, uses easily available materials, avoids use of expensive catalyst having toxic side effects, has low cost, and hence is good for market popularization. The raw material is cheap and easy to obtain, and the raw material is low cost. The method is simple and easy to operate, uses reagent that is low toxic or non-toxic, does not cause post-processing pollution to the environment, and easily recycles reagent to the final product, provides environmental protection, and is suitable for industrial production. The method provides product in higher yield, having good purity, little impurity, and low cost. The product has good antibacterial and growth promoting effects; has fast absorption, causes no accumulation, and has very important economic benefit and social benefit.    DETAILED DESCRIPTION - Chemical synthesis of quinoxaline-N,N-dioxide compound using 2-furazan N-oxide and ketone aldehyde oxime as raw materials in presence of alkaline catalyst to form intermediate quinoxaline-2-methyl-acyl oxime-1,4-dioxide, and continuously hydrolyzing under acidic condition and acetyl hydrazine to form target product, involves adding concentrated hydrochloric acid and acetone in reaction bottle, adding saturated aqueous solution of sodium nitrite at 0-5 degrees C, controlling reaction temperature at 0-10 degrees C, where the reaction time is 2-4 hours, after the reaction is finished, adjusting pH to be neutral with sodium hydroxide, recycling acetone, extracting with ethyl acetate, drying by anhydrous MgSO4, evaporating ethyl acetate to form colorless acicular crystal of acetone aldehyde oxime, adding halogenated hydrocarbon and 2-furazan N-oxide and solvent in reaction bottle, where solvent is 1-4C alcohol, diethyl ether, tetrahydrofuran, N,N-dimethyl formamide or acetonitrile, stirring to make it dissolve, conducting oxidation and completely dissolving 2-furazan, adding acetone oxime, adding alkali catalyst under condition of stirring, reacting for 12-20 hours, after the reaction is finished heating to 5 degrees C for 2 hours, filtering, washing the product by methanol to form yellow solid of quinoxaline-2-methyl-acyl oxime-1,4-dioxide, adding to the quinoxaline intermediate in the reaction bottle, water and acetyl hydrazine, then dripping concentrated sulfuric acid to react at 80 degrees C, after finishing dripping of concentrated sulfuric acid, heating at 80-100 degrees C for 4 hours, after the reaction is finished, reducing the temperature to room temperature for 2 hours, filtering, washing using water until the filtrate is neutral, and drying to form faint yellow liquid of the product, where the volume ratio of concentrated hydrochloric acid and acetone is 1:3-1:6, and the volume ratio of sodium nitrite saturated solution and concentrated hydrochloric acid is 1:1-1:2.