Phenylphenalenone glycosides: Occurrence, structure revision, and substituent effects on the steric orientation

Publication date: September 2017 Source:Phytochemistry Letters, Volume 21 Author(s): Bernd Schneider Glycosides and acyl glycosides of phenylphenalenones, phenylbenzoisochromenones, and structurally related natural products from plants are compiled. With the exception of one naphthalic anhydride glucoside from the Musaceae, all glycosides are chemotaxonomic markers of the Haemodoraceae, subfamily Haemodoroideae. NMR spectroscopic data indicate that in 6-O-glycosides of phenylphenalenones and phenylbenzoisochromenones, the substituents at C-5 and C-7 impede rotation of the interjacent sugar moiety at C-6. Furthermore, the structure of the acyl substituent at the C-6” hydroxyl group of some glucosides, previously reported as an allophanyl unit, in this review has been revised to a malonyl unit. Graphical abstract

Source: Phytochemistry Letters - June 23, 2017 Category: Chemistry Source Type: research