3,28-O-(2',2'-dimethylsuccinyl)-betulin diallyl ester 在
吗啉 、
四(三苯基膦)钯 作用下,
以78%的产率得到2,2-Dimethyl-succinic acid 1-[(1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-9-(3-carboxy-2,2-dimethyl-propionyloxy)-1-isopropenyl-5a,5b,8,8,11a-pentamethyl-icosahydro-cyclopenta[a]chrysen-3a-ylmethyl] ester