Abstract N-Substituted alkyl others, thioethers, sulfoxides, and sulfones of cyclic imides (eg, phthalimide, saccharin, 1, 8-naphthalimide, succinimide, and 2, 3-dihydrophthalazine-1, 4- dione) were shown to have potent hypolipidemic activity at doses of 10 and 20 mg/kg/d in rodents. These N-substitutions afforded no improvement over other known N-substitutions (eg, butyl, 3-butanone, or the propionic acid derivatives of phthalimide, saccharin, and 2, 3 ...