Cyclodepsipeptides from Beauveria bassiana. Part 3. The isolation of beauverolides Ba, Ca, Ja, and Ka
Abstract
Beauverolides Ja and Ka are shown to be the cyclotetradepsipeptides cyclo-[3-hydroxy-4-methyloctanoyl-L-tryptophyl-L-phenylalanyl-D-alloisoleucyl] and the 3-hydroxy-4-methyldecanoyl homologue, respectively. Pairs of beauverolides differing only in the hydroxy-acid residue are readily separated by high-pressure liquid chromatography and beauverolides Ba and Ca have been isolated using this technique.