Concise Total Synthesis of (±)-Deguelin and (±)-Tephrosin Using a Vinyl Iodide as a Key Building Block.

A concise and protecting-group-free total synthesis of the antiproliferative natural product (±)-deguelin (2) was accomplished in four steps and 62% overall yield from commercially available precursors. The key transformation employed a vinyl iodide as the pivotal building block to construct the 4-acylchromene substructure present in deguelin. Subsequent Cu2O-mediated α-hydroxylation of deguelin (2) afforded tephrosin (3) in 90% yield.