Six new furostanol saponins called trigoneosides Ia, Ib, IIa, IIb, IIIa, and IIIb were isolated from a medicinal foodstuff, fenugreek seed, the seed of Trigonella foenum-graecum L. (Leguminosae) originating from India, together with two known saponins, glycoside D and trigofoenoside A. The structures of trigoneosides Ia, Ib, IIa, IIb, IIIa, and IIIb were determined on the basis of chemical and physicochemical evidence as 26-O-β-D-glucopyranosyl-(25S)-5α-furostane-2α,3β,22ξ,26-tetraol 3-O-[β-D-xylopyranosyl(1→6)]-β-D-glucopyranoside, 26-O-β-D-glucopyranosyl-(25R)-5α-furostane-2α,3β,22ξ,26-tetraol 3-O-[β-D-xylopyranosyl(1→6)]-β-D-glucopyranoside, 26-O-β-D-glucopyranosyl-(25R)-5β-furostane-3β,22ξ,26-triol 3-O-[β-D-xylopyranosyl(1→6)]-β-D-glucopyranoside, 26-O-β-D-glucopyranosyl-(25R)-5 β-furostane-3β,22ξ,26-triol 3-O-[β-D-xylopyranosyl(1→6)]-β-D-glucopyranoside, 26-O-β-D-glucopyranosyl-(25S)-5α-furostane-3β,22ξ,26-triol 3-O-[α-L-rhamnopyranosyl(1→2)]-β-D-glucopyranoside, and 26-O-β-D-glucopyranosyl-(25R)-5α-furostane-3β,22ξ,26-triol 3-O-[α-L-rhamnopyranosyl(1→2)]-β-D-glucopyranoside, respectively.
medicinal foodstuff, Leguminosae, fenugreek, furostanol saponin, Trigonella foenum-graecum, trigoneoside
NCBI PubMed ID: 9023970Publication DOI: 10.1248/cpb.45.81Journal NLM ID: 0377775WWW link: http://ci.nii.ac.jp/naid/110003616372Publisher: Pharmaceutical Society Of Japan
Institutions: Kyoto Pharmaceutical University, Kyoto, Japan
Methods: 13C NMR, 1H NMR, NMR-2D, IR, FAB-MS, sugar analysis, TLC, acid hydrolysis, chemical methods, NMR-1D, methanolysis, HPLC, extraction, CC