Triterpene saponins from Medicago, truncatula aerial parts have been separated and their structures determined by the extensive use of 1D- and 2D-NMR experiments including H-1-H-1 (DQF-COSY, 1D-TOCSY) and H-1-C-13 (HSQC, HMBC) spectroscopy along with ESIMS. Fifteen individual compounds were isolated that included seven medicagenic acid and eight zanhic acid glycosides. Additionally, two soyasapogenol B and soyasapogenol E glycosides were identified by MS/MS and TLC. Four medicagenic acid glycosides (5, 11, 12, 14) and eight zanhic acid glycosides (1-4, 6-9) are reported here for the first time. The common feature of M. truncatula aerial part saponins is the (1 -> 3) linkage between the two glucose units at C-3 of medicagenic and zanhic acids, which is different from that found in alfalfa (Medicago sativa), where this linkage was always (1 -> 2). This may suggest differences in glucosyltransferases between these two Medicago species.
Triterpene Saponins from Barrel Medic (Medicago truncatula) Aerial Parts.
PERRONE, ANGELA;PIACENTE, Sonia;PIZZA, Cosimo;
2005
Abstract
Triterpene saponins from Medicago, truncatula aerial parts have been separated and their structures determined by the extensive use of 1D- and 2D-NMR experiments including H-1-H-1 (DQF-COSY, 1D-TOCSY) and H-1-C-13 (HSQC, HMBC) spectroscopy along with ESIMS. Fifteen individual compounds were isolated that included seven medicagenic acid and eight zanhic acid glycosides. Additionally, two soyasapogenol B and soyasapogenol E glycosides were identified by MS/MS and TLC. Four medicagenic acid glycosides (5, 11, 12, 14) and eight zanhic acid glycosides (1-4, 6-9) are reported here for the first time. The common feature of M. truncatula aerial part saponins is the (1 -> 3) linkage between the two glucose units at C-3 of medicagenic and zanhic acids, which is different from that found in alfalfa (Medicago sativa), where this linkage was always (1 -> 2). This may suggest differences in glucosyltransferases between these two Medicago species.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
