Reaction of lupane and oleanane triterpenoids with Lawessonʹs reagent

The reactions of selected triterpenic oxo compounds with Lawessonʹs reagent were investigated. We examined sulfurization of some oxygen compounds and for these reactions several hindered ketones, one aldehyde, α-hydroxyketones, esters, or anhydrides were chosen. We synthesized 15 new sulfur derivatives, including thioketone 16, dimeric sulfides 17–19, and thiaderivatives 20–22. We also observed unusual transformations, which afforded oxathiaphosphinines 23a, 23b, and dithiaphospholanes 24. The prepared compounds failed to demonstrate any significant cytotoxic activity.