Synthesis of DEFG Ring of Complestatin and Chloropeptin I:  Highly Atropdiastereoselective Macrocyclization by Intramolecular Suzuki-Miyaura Reaction

Palladium-catalyzed intramolecular Suzuki-Miyaura reaction of linear tripeptide (<b>23</b>) afforded the 16-membered DEFG ring of complestatin (<b>3</b>) in good yield with an excellent atropdiastereoselectivity. Acidic treatment of <b>3</b> triggers a stereospecific rearrangement leading to the corresponding DEFG ring <b>4</b> of chloropeptin I.