A series of novel 4-arylsulfonyl-3,4-dihydro-2(1H)-quinoxalinone-1-alkanoic acid compounds have been prepared, including their lower alkyl ester derivatives, as well as the base salts of said acids with pharmacologically acceptable cations. These particular compounds are useful in therapy as agents for the control of certain chronic diabetic complications. Typical members include those compounds derived from 3,4-di-hydro-2-(1H)-quinoxalinone-1-acetic acid wherein an unsubstituted or substituted phenylsulfonyl moiety is located at the 4-position of the molecule. Ethyl 4-benzenesulfonyl-3,4-dihydro-2(1H)-quinoxalinone-1-acetate and 4-benzenesulfonyl-3,4-dihydro-2(1H)-quinoxalinone-1-acetic acid represent typical and preferred member compounds. Methods for preparing all these compounds from known starting materials are provided.