Seven pyrrolizidine alkaloids (PAs) have been isolated from Lithospermum canescens and their structures determined by spectroscopical methods. Besides the known lycopsamine, O7- acetyl-lycopsamine and O7-acetylintermedine four new PAs were found. Their structures are O7-(3-hydroxy-3-methyl-butanoyl)-O9-(+)-trachelanthoyl-heliotridine (= O7-(3-hydroxy-3- methyl-butanoyl)-rinderine = canescine), O7-(3-hydroxy-3-methyl-butanoyl)-O9-(D)-viridifloryl- heliotridine (= O7-(3-hydroxy-3-methyl-butanoyl)-echinatine = canescenine) and their O13-acetyl-derivatives (= acetylcanescine; acetylcanescenine).
A Journal of Biosciences: Zeitschrift für Naturforschung C (ZNC) is an international scientific journal for the emerging field of natural and natural-like products. ZNC publishes original research on the isolation, bio-chemical synthesis and bioactivities of natural products, their biochemistry, pharmacology, biotechnology, and biological activity and innovative developed computational methods for predicting their structure and/or function.