Some novel 2-methyl-3-aminopropiophenones were synthesized and their centrally acting muscle relaxant activities were evaluated for an inhibitory effect on the flexor reflex in rats. The structure-activity relationships are discussed. In this series, 2-methyl-3-pyrrolidino-1-(4- trifluoromethylphenyl)-propan-1-one (28) showed significant centrally acting muscle relaxant activity. In addition, the activities of each enantiomer (28-(S) and (R) were studied along ...