Formal total synthesis of coriolin has been accomplished on the basis of a [3+2] cycloaddition reaction of a vinylsulfide with 3-(methylthio)-2-siloxyallyl cation. A five-membered vinylsulfide as a C ring unit was prepared in five steps from commercially available compounds. The first [3+2] cycloaddition reaction gave the BC ring intermediate, which was then converted into a bicyclic vinylsulfide in three steps. The construction of the A ring by the second [3+2] cycloaddition reaction followed by two-step-conversion afforded the tricyclic enone (30% overall yield from isobutyronitrile) which has previously been synthesized and converted into coriolin.
Domon, K., Masuya, K., Tanino, K., & Kuwajima, I. (1997). Highly efficient method for coriolin synthesis. Tetrahedron Letters, 38(3), 465–468. https://doi.org/10.1016/S0040-4039(96)02328-3