Investigation of aqueous methanol extracts of the cyanobacterium Nodularia spumigena KAC 66 led to the isolation of the nodulopeptins 899, 901 and 917. The chemical structures were determined using high-resolution NMR and MS-data. The stereochemistry of the amino-acid residues was realized by LC-MS analysis using Marfey's reagent. The bioactivity of the novel compounds was determined.
- Structure determination