Efficient synthetic route toward the cyclic, cysteine-containing natural products FK228 and the spiruchostatins

ORGN 840

Kimberly A. Kocak, Katherine A. Perri, Yim Ling Cheng, and Justin S. Miller, jsmiller@hws.edu. Department of Chemistry, Hobart and William Smith Colleges, 300 Pulteney Street, Geneva, NY 14456
Progress along a new, straightforward synthetic route toward depsipeptides FK228 and the Spiruchostatins is described. The key step will involve macrocyclization via pseudo-native chemical ligation (NCL) of an N-terminal D-cysteine (D-Cys) residue and a latent C-terminal thioester functional group, called a thioester equivalent, that is stable under the conditions traditionally used for peptide synthesis. As the target compounds are cyclic peptides, each with a single ester linkage, they are envisioned to arise synthetically via straightforward peptide synthesis using their constituent hydroxy- and amino acid subunits. Furthermore, because a thioester equivalent functional group can be incorporated into a linker for solid-phase synthesis, the solution-phase route illustrated herein is adaptable to the solid phase with no modifications. Synthesis of analogs of the title depsipeptides would therefore be a simple matter of entering different starting materials into SPPS. New compounds could thus be generated on demand using commercially available amino acids.
 

Combinatorial, Parallel and Process Chemistry, Heterocycles, Aromatics, New Reactions and Methodology
8:00 PM-10:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Sci-Mix

Division of Organic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007