A number of new 3,4-dialkylsydnones have been prepared to compare their pharmacological properties with those of a series of 3-alkylsydnones. Both series were similar in their central convulsive activity. The CD 50 and partition coefficient values of both series were compared. The CD 50 values for the 3,4-dialkylsydnones were significantly lower than for the 3-alkylsydnones. In addition, the CD 50