Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Conjugates of 3,7‐trans cucurbic acid isomers with either (S )‐ or (R )‐isoleucine were synthesised from the diastereomeric conjugate of (3R , 7R )‐jasmonic acid and (3S , 7S )‐jasmonic acid by sodium borohydride reduction. The resulting diastereomers were characterised by nuclear magnetic resonance spectra. The authentic substances were subjected to liquid chromatography using a reversed‐phase C18 matrix and the chiral stationary phase Chiralpak AS. For all (6RS )‐hydroxy epimeric pairs, a baseline separation could be observed. The elution sequences obtained indicate that the 3,6‐trans oriented epimers with (S )‐isoleucine elute prior to the 3,6‐cis configured individuals independent of the mode of chromatography. In contrast, the elution pattern of the conjugates containing (R )‐isoleucine was reversed on the chiral stationary phase. The epimers with a 3,6‐cis configured hydroxy group and the acid side chain eluted faster than those with the 3,6‐trans configuration. The chromatographic conditions described are suitable for resolving mixtures of isomeric N‐(cucurbinoyl)‐isoleucines in order to assign their stereochemistry and to obtain chiral reference materials on a preparative scale.