Biologically Active Triterpenoid Saponins from Ardisia japonica

Abstract

Eleven new triterpenoid saponins, ardisianosides A (1), B (2), C (4), D (5), E (6), F (7), G (15), H (16), I (17), J (18), and K (19), together with 10 known saponins, were isolated from the whole plants of Ardisia japonica. The structures of the new saponins were established on the basis of extensive 1D and 2D NMR and MS studies coupled with chemical degradations. The cytotoxic activities of saponins 1-21 are reported against three human cancer cell lines, namely, HL-60 myeloid leukemia, KATO-III stomach adenocarcinoma, and A549 lung adenocarcinoma cells.

Cytotoxic triterpenoid saponins from Clematis tangutica

“…Furthermore, the oleanolic acid of 1 was obtained by acid hydrolysis, and was identified by ESIMS and NMR analysis. (Chang et al, 2007). For the rhamnose unit, the large 1 J C1, H1…”

Triterpene saponins of Maesa lanceolata leaves

“…In the 1 H NMR spectrum, an oxymethine proton at δ 3.50 (dd, J=11.6, 4.3 Hz, H-3) was coupled to two other protons and from decoupling experiments, it was shown to be part of -CH2-CH-(O-glc)-C(CH3)2-CH-system analogous to the C-2 to C-5 region in oleanane skeleton. 18 This allowed the oligosaccharide attached to the aglycone to be assigned to C-3 where it is in equatorial configuration, a fact further supported by the HMBC cross-peak between H-1' (δ 4.72) and C-3 (δ 80.1), and confirmed by NOESY cross-peaks between H-3 and Me-23 (δ 1.14 s) and also in turn with H-5.…”

“…Hence, sequence of saccharide moiety was evaluated as 13 C NMR peaks at δ 180.4 (C-28) and 92.6 (C-13) suggested that the aglycone is an oleanane derived triterpenoid (C30) skeleton with oxygen functionalities in positions C-3, C-16, C-21 and C-22 in addition to the epoxy-γ-lactone moiety at C-13 and C-28. 18 The presence of the latter functionality was further supported by IR spectrum characteristic peaks at 1758 and 875 cm -1 . 24,25,26 The downfield shift of the 1 H NMR signal at δ 4.96 suggested the presence of an acetyl group and was confirmed by HMBC cross-peak between the H-22 (δ 4.96) and δ 171.0 (acetyl group) to be at C-22.…”

“…19 The position of the oligosaccharide unit on the aglycone was established from HMBC experiments to be attached glycosidically at C-3 and from spin decoupling experiment it was in β-configuration. 18 The presence of key HMBC correlations between H-16 (δ 4.34)/ H-18 (δ 2.56) and C-22 (δ 74.4); between H-16/H-18/ H-22 (δ 5.21) and C-28 (δ 203.3), and between H-22 and the acetyl group (δ 170.2) unambiguously confirmed the disposition of hydroxyl, acetyl and aldehyde groups at C-16, C-22 and C-28, respectively on the aglycone, a fact further confirmed by NOESY plot (Fig. 1).…”

Two New Guaiane-Type Sesquiterpene Glycosides from the Fruits of Daucus carota L.

“…The previous research on chemical constituents of D. carota has carried out the presence of sesquiterpenes, [6][7][8] chromones, 9) flavonoids, 10,11) coumarins 6,12) and anthocyanins. 13,14) As a part of our ongoing investigation on bioactive constituents, [15][16][17][18] we initiated a phytochemical investigation on the fruits of D. carota L., which resulted in the isolation of two new guaiane-type sesquiterpene glycosides, 11-O-acetyl-torilolone 8-O-b-D-glucopyranoside (1) and 1b-hydroxytorilolone 11-O-b-D-glucopyranoside (2). In this paper, we report the isolation and structure elucidation of them.…”