Several natural products are currently used for the treatment of cancer, the most important of which is paclitaxol. However, this, and other drugs are not effective against all types of cancer, and cellular resistance to these treatments has begun to emerge. Laulimalide is a marine macrolide that displays potent anti-cancer activity and has the potential to develop into a new and effective treatment. Therefore, a synthetic route that would allow access to large quantities of laulimalide and its derivatives would prove to be a valuable asset to drug development. Research in the Trost laboratories has developed several catalytic asymmetric methodologies that will be applied to the synthesis of the laulimalide macrocycle. In addition, the total synthesis of laulimalide will facilitate the development of several new protocols that will have broad synthetic applications. In particular, a new hetero Diels-Alder catalyst will be developed for the reaction of unactivated aldehydes with simple dienes. The proposed research will facilitate an efficient and atom economical synthesis of laulimalide, while at the same time, provide new synthetic tools for the chemist to use in the assembly of other biologically important molecules. [unreadable] [unreadable]