1-Acyl-3-O-[β-glucopyranosyl-(1″→6′)-β-glucopyranosyl]-glycerols and Cordycedipeptides B and C, New Metabolites from Bacillus pumilus

Abstract

Four 1-monoacyl-3-O-[β-glucopyranosyl-(1→6)-β-glucopyranosyl]-glycerols (1) and four 1,2-diacyl-3-O-[β-glucopyranosyl-(1→6)-β-glucopyranosyl]-glycerols (2a) with acyl residues consisting of 1:1 mixtures of 1-iso-pentadecanoyl- and 1-anteiso-pentadecanoyl residues and the respective heptadecanoic acid isomers s as main components, have been characterized in the extracts of Bacillus pumilus strain DKS1. Twenty-seven further metabolites, among them the diketopiperazines cordycedipeptide A (3), B (4), and C (5), were obtained. All compounds were elucidated by NMR and MS techniques and fully characterized and tested for antimicrobial activity against Legionella pneumophila.