The hydrophilic extract of Microcystis sp. bloom material collected from Bror Hayil Reservoir in southern Israel afforded four new metabolites, (2 S,3 S)-3-hydeoxy-1,4-diphenylbutan-2-yl-acetate, aeruginosins BH604, BH462A and BH462B, and two known metabolites cyanopeptolins S and SS. The planar structure of 1–4 was established by analyses of their 1D and 2D NMR data and mass spectrometric data. The absolute configurations of the chiral centers of 1 were established by Mosher method and analysis of the coupling constants between H-2 and H-3, and those of 2–4 by Merfay's method and advanced Merfay's method and chiral HPLC. The compounds do not inhibit the serine proteases trypsin and thrombin.
Aranochlor A and Aranochlor B, Two New Metabolites from Pseudoarachniotus roseus: Production, Isolation, Structure Elucidation and Biological Properties.