Journal of the American Chemical Society, Vol.140, No.16, 5365-5369, 2018
Asymmetric Total Synthesis of Cyclocitrinol
The first and asymmetric total synthesis of cyclocitrinol, an unusual C25 steroid, has been accomplished in a linear sequence of 18 steps from commercially available compound 11. The synthetically challenging bicyclo[4.4.1] A/B ring system with a strained bridgehead (anti-Bredt) double bond of cyclocitrinol was constructed efficiently and diastereoselectively via a type II intramolecular [5 + 2] cycloaddition.