Synthesis of Some Di- and Tridepsipeptides Containing Hydroxy-methylbutyric Acid Involved in the Structure of a Depsipeptide Isolated from the Mushroom Sarcodon scabrosus

Abstract

Some di- and tridepsipeptides containing hydroxymethylbutyric acid were synthesized. A comparison of their NMR spectra with those of the degradation products from the Sarcodon scarbrosus depsipeptide enabled assigning the natural compound preferentially to be cyclo-Hmb-Ile-Hmb-Ala-Thr-. The configuration of the residue of Hmb-Ile is postulated to be L-L, although it could possibly be D-D.