Ferrocenyltriazoles from 3β,28-Diacylbetulin: Synthesis and Cytotoxic Activity

The reaction of 30-bromo-3β,28-diacylbetulin with sodium azide afforded 30-azido-3β,28-diacyloxylup-20(29)-enes. The products were subjected to a CuI/TMEDA-catalyzed click reaction with ethynylferrocene to obtain the corresponding ferrocene-betulin conjugates with a 1,2,3-triazole linker.