3'-Substituted propanolursolates (1) were obtained by a reaction of ursolic acid with trimethylene bromide. This intermediate reacted with several N-containing compounds to afford a series of new derivatives 2a～2j. The structures of new products were characterized by means of ¹H NMR, ¹³C NMR, IR and MS techniques. The preliminary bioassay test shows that several compounds give a good antitumor activity, and most of them are better than that of parent ursolic acid. Among them, compound 2e shows the best activity.

Key words: ursolic acid, 3'-substituted propanolursolate, synthesis, antitumor activity