A concise and modular
total synthesis of the highly potent N
14
-desacetoxytubulysin
H (
1
) has been accomplished in 18 steps in an overall
yield of up to 30%. Our work highlights the complexity–augmenting
and route-shortening power of diastereoselective multicomponent reaction
(MCR) as well as the role of bulky ligands to perfectly control both
the regioselective and diastereoselective synthesis of tubuphenylalanine
in just two steps. The total synthesis not only provides an operationally
simple and step economy but will also stimulate major advances in
the development of new tubulysin analogues.