65892-76-4Relevant academic research and scientific papers
Artefact formation during acid hydrolysis of saponins from Medicago spp.
Tava, Aldo,Biazzi, Elisa,Mella, Mariella,Quadrelli, Paolo,Avato, Pinarosa
, p. 116 - 127 (2017/04/13)
Artefact compounds obtained during acid hydrolysis of saponins from Medicago spp. (Fabaceae), have been monitored and evaluated by GC-FID. Their identification has been performed by GC-MS and 1H and 13C NMR. Saponins with different substituents on the triterpenic pentacyclic aglycones were considered, and their hydrolysis products were detected and quantified during 10?h of time course reaction. From soyasapogenol B glycoside the well known soyasapogenols B, C, D and F were obtained together with a previously undescribed sapogenol artefact identified as 3β,22β,24-trihydroxyolean-18(19)-en and named soyasapogenol H. From a zanhic acid saponin two major artefact compounds identified as 2β,3β,16α-trihydroxyolean-13(18)-en-23,28-dioic acid and 2β,3β,16α-trihydroxyolean-28,13β-olide-23-oic acid were obtained, together with some zanhic acid. Other compounds, detected in very small amount in the reaction mixture, were also tentatively identified based on their GC-MS and UV spectra. The other most characteristic saponins in Medicago spp., hederagenin, bayogenin and medicagenic acid glycosides, under acidic condition of hydrolysis, released instead the correspondent aglycones and generated a negligible amount of artefacts. Nature of artefacts and mechanism of their formation, involving a stable tertiary carbocation, is here proposed and discussed for the first time.
New triterpenic saponins from the aerial parts of Medicago arabica (L.) Huds
Tava, Aldo,Mella, Mariella,Avato, Pinarosa,Biazzi, Elisa,Pecetti, Luciano,Bialy, Zbigniew,Jurzysta, Marian
experimental part, p. 2826 - 2835 (2010/06/11)
The reinvestigation of saponin composition from Medicago arabica from Italy allowed the detection of nineteen (1-19) saponins. All of them were purified by reverse-phase chromatography and their structures elucidated by spectroscopic and spectrometric (1D and 2D NMR; ESI-MS/MS) and chemical methods. Fourteen were known saponins, previously found in other plants including other Medicago species. They have been identified as glycosides of oleanolic acid, 2β,3β-dihydroxyolean-12-en-28-oic acid, hederagenin, bayogenin and soyasapogenol B. Five saponins, identified as 3-O-[-α-L- arabinopyranosyl(1→2)-β-D-glucuronopyranosyl]-30-O-β-D- glucopyranosyl 2β,3β,30-trihydroxyolean-12-en-28-oic acid (1), 3-O-[α-L-arabinopyranosyl(1→2)-β-D-glucuronopyranosyl] -30-O-[β-D-glucopyranosyl]3β,30-dihydroxyolean-12-en-28-oic acid (2), 3-O-|β-D-glucuronopyranosyl]-30-O-[α-L-arabinopyranosyl(1→2) -β-D-glucopyranosyl] 2β,3β,30-trihydroxyolean-12-en-28-oic acid (3), 3-O-[β-D-glucuronopyranosyl]-30-O-[α-L- arabinopyranosyl(1→2)-β-D-glucopyranosyl] 3β,30-dihydroxyolean- 12-en-28-oic acid (4) and 3-O-[β-D-glucuronopyranosyl]-30-O-[β-D- glucopyranosyl] 2β,3β,30-trihydroxyolean-12-en-28-oic acid (5), are reported here as new natural compounds. These new saponins, possessing a hydroxy group at the 30-methyl position of the triterpenic skeleton, have never been previously found in the genus Medicago.
