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.
Titolo: | Triterpene Saponins from Barrel Medic (Medicago truncatula) Aerial Parts. | |
Autori: | ||
Data di pubblicazione: | 2005 | |
Rivista: | ||
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. | |
Handle: | http://hdl.handle.net/11386/1058325 | |
Appare nelle tipologie: | 1.1.2 Articolo su rivista con ISSN |