Total synthesis of dolastatin 10 through ruthenium-catalyzed asymmetric hydrogenations

A total synthesis of dolastatin 10, a potent inhibitor of microtubule assembly, which displayed remarkable antineoplastic activity, is reported. Our synthetic approach was based upon ruthenium-promoted asymmetric hydrogenation of β-keto esters derived from (S)-Boc-proline and (S)-Boc-isoleucine for the construction of the two key units: (2R,3R)-Boc-dolaproine (Dap) and (3R)-Boc-dolaisoleucine (Dil).