Medusamide A, a Panamanian Cyanobacterial Depsipeptide with Multiple β-Amino Acids

Researchers have discovered medusamide A, a novel cyclic depsipeptide from marine cyanobacteria collected in Coiba National Park, Panama. This compound is notable for containing four contiguous β-amino acid residues, specifically (2R,3R)-3-amino-2-methylhexanoic acid (Amha), marking the first report of multiple Amha residues within a single cyclic peptide-type natural product. The stereochemical assignment of these residues was achieved through synthesis of reference standards and derivatization with Marfey's reagent, followed by LC-MS analysis.

Fenner, A. M., Engene, N., Spadafora, C., Gerwick, W. H., & Balunas, M. J. (2016). Medusamide A, a Panamanian Cyanobacterial Depsipeptide with Multiple β-Amino Acids. Organic Letters, 18(3), 352–355. https://doi.org/10.1021/acs.orglett.5b03110