Spirostane-Type Saponins Obtained from Yucca schidigera

Abstract

It is well known that spirostane-type saponins show various bioactivities. In our on-going program of screening these kinds of constituents from natural products, Yucca schidigera was found to be rich in them, and nine new spirostanol saponins, Yucca spirostanosides A1 (1), A2 (2), B1 (3), B2 (4), B3 (5), C1 (6), C2 (7), C3 (8), and D1 (9), together with five known ones (10–14) were isolated from the plant. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR and MS spectra, and comparing with published data.

New Dammarane-Type Triterpenoid Saponins from Panax notoginseng Leaves and Their Nitric Oxide Inhibitory Activities

“…Consequently, the structure of notoginsenoside NL-C 1 (8) was elucidated. d-glucose and d-xylose were given [12]. Its 1 H and 13 C-NMR (Table 9) spectra were similar to those of 8.…”

“…The IR spectrum showed the absorption bands assignable to hydroxyl (3395 cm -1 ), olefin (1645 cm -1 ), and ether (1078 cm -1 ) functions, respectively. Acid hydrolysis of 1 followed by HPLC analysis confirmed the presence of D-glucose and L-arabinose [12]. The 1 H and 13 C-NMR (Table 1) .…”

“…The IR spectrum showed the absorption bands assignable to hydroxyl (3395 cm −1 ), olefin (1645 cm −1 ), and ether (1078 cm −1 ) functions, respectively. Acid hydrolysis of 1 followed by HPLC analysis confirmed the presence of d-glucose and l-arabinose [12]. The 1 H and 13 C-NMR (Table 1) spectra of 1 displayed the signals of two β-d-glucopyranosyls [δ 4.95 (1H, d, J = 8.0 Hz, H-1 ), 5.18 (1H, d, J = 8.0 Hz, H-1 )], and one α-l-arabinofuranosyl [δ 5.66 (1H, d, J = 1.5 Hz, H-1 )].…”

“…Its IR spectrum exhibited absorption maxima at 3379, 1649 and 1076 cm −1 , accounting for the hydroxyl, olefinic bond, and ether function, respectively. d-glucose and l-arabinose were detected from its acid hydrolysis product [12]. Its 1 H and 13 C-NMR (Table 5) (Tables 6 and 7), 1 H-1 H COSY, HSQC, HMBC, and HSQC-TOCSY spectral characteristics, the aglycones of both 6 and 7 were identified as 3β,12β,20(S),25-tetrahydroxydammar-23-ene, too.…”

“…Its 1 H and 13 C-NMR (Table 5) (Tables 6 and 7), 1 H-1 H COSY, HSQC, HMBC, and HSQC-TOCSY spectral characteristics, the aglycones of both 6 and 7 were identified as 3β,12β,20(S),25-tetrahydroxydammar-23-ene, too. Moreover, by comparing to 3, we could deduce that 6 had the same glycosyl moieties as 3. d-glucose, l-arabinose, and d-xylose were yielded from its acid hydrolysis reaction [12]. Moreover, the long-range correlations from δ H 4.92 (H-1 ) to δ C 89.0 (C-3); δ H 5.50 (H-1 ) to δ C 83.0 (C-2 ); δ H 5.39 (H-1 ) to δ C 84.6 (C-2 ); δ H 5.16 (H-1 ) to δ C 83.4 (C-20); and δ H 5.64 (H-1 ) to δ C 68.4 (C-6 ) were observed in the HMBC experiment ( Figure 2).…”