Two ways are shown to transform cardioactive cardenolides into cardenamides [17β-(5-oxo-2,5-dihydropyrrol-3-yl)-5β,14β-androstane derivatives], and their derivatives by replacement of their ring oxygen by N-R. Cardioactivity is strongly decreased by this transformation. The comparatively easily accessible 21-oxocardenamides [17β-(2-maleimidyl)steroids] are strongly thiol reactive and show remarkable anticancer activity.
展示了两种将心脏活性心苷转化为卡德纳胺类化合物[17β-(5-氧代-2,5-二氢吡咯-3-基)-5β,14β-雄甾烷衍生物]及其衍生物的方法,通过用N-R替换其环氧基。这种转化会大大降低心脏活性。相对容易获取的21-氧代卡德纳胺类化合物[17β-(2-马来酰亚胺基)类固醇]具有很强的巯基反应性,并表现出显著的抗癌活性。