A short and efficient synthesis of (-)-7-methylomuralide, a potent proteasome inhibitor.

Short, practical, and scalable syntheses of (+/-)-7-methylomuralide and (-)-7-methylomuralide have been developed. Three consecutive tandem reaction pairs establish all of the carbons and the stereochemistry of the target molecule, vastly simplifying the synthetic scheme from N-trichloroethoxycarbonyl glycine. The chiral directing group controls the absolute stereochemistry of the key aldol reaction.