3-epi-betulinic acid 28-O-<α-L-rhamnopyranosyl(1->4)-O-β-D-glucopyranosyl(1->6)>-β-D-glucopyranoside   、                                                                                      
碘甲烷                                                                                                                                                              在
                                                                                                                                                                                 
sodium hydroxide   、                                                                                                  
sodium t-butanolate                                                                                                                                  作用下,
                                                                                                                以
                                                                                         
二甲基亚砜                                                                                  为溶剂,
                                                                                                                                                    反应 1.0h,
                                                                                                                以40 mg的产率得到[(2S,3R,4S,5R,6R)-6-[[(2R,3R,4S,5R,6R)-3,4-dimethoxy-6-(methoxymethyl)-5-[(2S,3R,4R,5S,6S)-3,4,5-trimethoxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-3,4,5-trimethoxyoxan-2-yl] (1R,3aS,5aR,5bR,7aR,9R,11aR,11bR,13aR,13bR)-9-methoxy-5a,5b,8,8,11a-pentamethyl-1-prop-1-en-2-yl-1,2,3,4,5,6,7,7a,9,10,11,11b,12,13,13a,13b-hexadecahydrocyclopenta[a]chrysene-3a-carboxylate