New Triterpenoid Saponins from Bulbs of Bolbostemma paniculatum

Abstract

Nine new triterpenoid saponins were isolated from the bulbs of Bolbostemma paniculatum (Maxim.) Franquet (Cucurbitaceae): 7β,18,20,26-tetrahydroxy-(20S)-dammar-24E-en-3-O-α-L-(3-acetyl)arabinopyranosyl-(1→2)-β-D-glucopyranoside, 7β,18,20,26-tetrahydroxy-(20S)-dammar-24E-en-3-O-α-L-(4-acetyl)arabinopyranosyl-(1→2)-β-D-glucopyranoside, 7β,18,20,26-tetrahydroxy-(20S)-dammar-24E-en-3-O-α-L-arabinopyranosyl-(1→2)-β-D-(6-acetyl)glucopyranoside, 7β,20,26-trihydroxy-(20S)-dammar-24E-en-3-O-α-L-arabinopyranosyl-(1→2)-β-D-glucopyranoside, 7β,20,26-trihydroxy-(20S)-dammar-24E-en-3-O-α-L-(3-acetyl)arabinopyranosyl-(1→2)-β-D-glucopyranoside, 7β,20,26-trihydroxy-(20S)-dammar-24E-en-3-O-α-L-(4-acetyl)arabinopyranosyl-(1→2)-β-D-glucopyranoside, 7β,20,26-trihydroxy-8-formyl-(20S)-dammar-24E-en-3-O-α-L-(3-acetyl)arabinopyranosyl-(1→2)-β-D-glucopyranoside, 7β,20,26-trihydroxy-8-formyl-(20S)-dammar-24E-en-3-O-α-L-(4-acetyl)arabinopyranosyl-(1→2)-β-D-glucopyranoside and 6′-O-palmitoyltubeimoside I. In addition, four known triterpenoid saponins: tubeimoside I, tubeimoside II, tubeimoside III and tubeimoside IV were isolated. The structures of the above compounds were elucidated based on spectroscopic studies, and the configuration of C-20 of tubeimoside IV was revised as S rather than R as reported in previous literature. The compounds were tested for their antiviral activity

Key words

Bolbostemma paniculatum - Cucurbitaceae - triterpenoid saponins - dammarane triterpenes - antiviral activity

References

• 1 Kong F H, Zhu D Y, Xu R S, Fu Z C, Zhou L Y, Iwashita T. et al . Structural study of tubeimoside I, a constituent of Tu-Bei-Mu.  Tetrahedron Letters. 1986;  27 5765-8
• 2 Kasai R, Miyakoshi M, Nie R -L, Zhou J, Matsumoto K, Morita T. et al . Saponins from Bolbostemma paniculatum: cyclic bisdesmosides, tubeimosides II and III.  Phytochemistry. 1988;  27 1439-46
• 3 Marino S D, Borbone N, Iorizzi M, Esposito G, McClintock J B, Zollo F. Bioactive asterosaponins from the starfish Luidia quinaria and Psilaster cassiope. Isolation and structure characterization by two-dimensional NMR spectroscopy.  J Nat Prod. 2003;  66 515-9
• 4 Plaza A, Cinco M, Tubaro A, Pizza C, Piacente S. New triterpene glycosides from the stems of Anomospermum frandifolium .  J Nat Prod. 2003;  66 1606-10
• 5 Xu S -Y, Bian R -L, Chen X. Pharmacological Experiment Method. 2nd Edition Beijing; Peoples medical publishing house 1991: pp 1397-405
• 6 Kong F -H, Zhu D -Y, Xu R -S, Fu Z -C. Studies on the chemical constituents of Bolbostemma paniculatun [Maxim] Franquet (IV). The structure of tubeimoside II, III and IV.  Acta Chimica Sinica. 1988;  46 409-11
• 7 Iwamoto M, Fujioka T, Okabe H, Mihashi K, Yamauchi T. Studies on the constituents of Actinostemma lobatum Maxim. I. Structures of actinostemmosides A, B, C and D, dammarane triterpene glycosides isolated from the herb.  Chem Pharm Bull. 1987;  35 553-61
• 8 Asakawa J, Kasai R, Yamasaki K, Tanaka O. ¹³C NMR study of ginseng sapogenins and their related dammarane type triterpenes.  Tetrahedron. 1977;  33 1935-9