Journal of the American Chemical Society, Vol.132, No.29, 9968-9969, 2010
A Biomimetic Approach to C-nor-D-homo-Steroids
A biomimetic three-step transformation of classical "6-6-6-5"-steroids into their C-nor-D-homo-counterparts gives an easy and fast access to this highly important substructure of natural products, as it is found in cyclopamine, and nakiterpiosin. A novel reagent combination allows for the rearrangement even of 17-keto steroids with high endoselectivity. In several examples the broadness of this strategy is outlined.