MS-681a, b, c and d, new inhibitors of myosin light chain kinase from Myrothecium sp. II. Physico-chemical properties and structure elucidation

Article abstract of DOI:10.7164/antibiotics.50.998

MS-681a, b, c and d are new inhibitors of myosin light chain kinase produced by Myrothecium sp. They are novel octapeptides containing α-alkyl-α-amino acids and a polyamine moiety. The structures were determined by NMR and FAB-MS/MS spectral analyses of the intact peptides. Their absolute configurations were elucidated by GC analysis on a chiral column of the constituent amino acids and by chemical synthesis of the polyamine moieties.