Five new cyotoxic steroidal glycosides from the fruits of Solanum torvum

The fruits of Solanum torvum Swartz, commonly known as Turkey berry, are edible and commonly used as a vegetable in the South Indian population's diet and as an essential ingredient in Thai cuisine. Five new steroidal glycosides together with five known ones were isolated from the fruits of S. torvum Swartz. Based on chemical and spectral evidence, the five new compounds were identified to be 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3β,6α,26-triol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-O-β-d-quinovopyranoside] (1), 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3-one-6α,26-diol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-O-β-d-quinovopyranoside] (2), 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3β,6α,26-triol-6-O-β-d-quinovopyranoside (3), 5α-pregn-16-en-20-one-3β,6α-diol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-β-d-quinovopyranoside] (4), and 5α-pregn-16-en-3,20-dione-6α-ol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-β-d-quinovopyranoside] (5). These new compounds were assayed for cytotoxicities in vitro, and 1 to 4 showed cyotoxic activity against the human melanoma cell line A375, with IC₅₀ values of 30 μM to 260 μM.     

Three new phenolic compounds from the leaves of Rosa sericea

Two new flavonoids, quercetin-3-O-β-d-xylopyranosyl-(1 → 2)-α-d-ribopyranoside (1) and kaempferol-3-O-β-d-xylopyranosyl-(1 → 2)-α-d-ribopyranoside (2), and one new phenolic derivative, gallicin-p-O-(6′-O-caffeoyl)-β-d-glucoside (3), together with twelve known compounds were isolated from the leaves of Rosa sericea (Rosaceae family). The structures of the new compounds were established by means of spectroscopic analysis including one- and two-dimensional NMR spectroscopy. Some of the isolated compounds were tested for the cytotoxicity of a breast cancer cell (MCF-7) line. The results showed that rubanthrone A (4) has moderate cytotoxicity against the MCF-7 cell line.     

Chemical constituents of Swertia yunnanensis and their anti-hepatitis B virus activity

Four new triterpenoids, sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4), along with nineteen known compounds (5–23) were isolated from Swertia yunnanensis. Based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR, [α]_D), the structures of sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4) were elucidated as taraxer-14-ene-3α,6β-diol, oleanolic acid 28-O-β-d-glucopyranosyl-(1 → 2)-O-β-d-glucopyranoside, 2α,3β-di-hydroxyolean-12-en-28-oic acid 28-O-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl (1 → 6)-β-d-glucopyranosyl(1 → 2)-β-d-glucopyranoside and hederagenin 28-O-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl(1 → 2)-β-d-glucopyranoside, respectively. Twenty-two compounds were evaluated for their anti-HBV activities on the HepG 2.2.15 cell line in vitro, of which nine compounds showed potent anti-HBV activities. Compounds 1, 5–6, 14–16 and 19 showed activities against the secretion of HBsAg (IC₅₀ values from 0.10 to 1.76 mM) and HBeAg (IC₅₀ values from 0.04 to 1.41 mM), and compounds 11 and 13–16 exhibited significant inhibition on HBV DNA replication (IC₅₀ values from 0.01 to 0.09 mM).     

Five new triterpenoidal saponins from the roots of Ilex cornuta and their protective effects against H2O2-induced cardiomyocytes injury

Five new ursane-type triterpenoidal saponins (1–5), together with five known ones (6–10), were isolated from the EtOH extract of the roots of Ilex cornuta. The structures of saponins 1–5 were elucidated as 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside (1), 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside-6-O-ethyl ester (2), 19α-hydroxyurs-12-en-28-oic acid 3β-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranoside (3), 3β-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranosyl]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (4) and 3β-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranoside-6-O-methyl ester]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (5), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and chemical reactions. Protective effects of compounds 1–10 against H₂O₂-induced H9c2 cardiomyocyte injury were tested. Compounds 1–5, 7, and 10 showed cell-protective effects. Among them compound 5 exhibited the highest activity. No significant DPPH radical scavenging activity was observed for compounds 1–10.     

New cytotoxic triterpenoid saponins from the whole plant of Clematis lasiandra Maxim

Four new oleanane type triterpenoid saponins (1–4) and three known saponins (5–7) were isolated from the whole plant of Clematis lasiandra Maxim. The structures of the four new compounds were elucidated as 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-β-d-xylopyranosyl hederagenin (1), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl oleanolic acid 28-O-β-d-glucopyranosyl ester (2), 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl hederagenin (3) and 3-O-β-d-ribopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-[β-d-glucopyranosyl-(1 → 4)]-α-l-arabinopyranosyl hederagenin (4) on the basis of extensive spectroscopic analysis and chemical evidence. Compounds 1–7 were evaluated for their cytotoxicity against human tumor cell lines HL-60, Hep-G2 and SGC-7901, and all of the evaluated saponins showed significant cytotoxicity to those three tumor cell lines with IC₅₀ in the range from 1.40 to 19.50 μmol/L except for compounds 2 and 6.     

Two new steroidal saponins from Selaginella uncinata (Desv.) Spring and their protective effect against anoxia

Four steroidal saponins were isolated from the anti-anoxic fraction of the 60% EtOH extract of Selaginella uncinata, including two new compounds, (3β, 7β, 12β, 25R)-spirost-5-ene-3, 7, 12-triol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 4)]-O-β-d-glucopyranoside (1), (2α, 3β, 12β, 25R)-spirost-5-ene-2, 3, 12-triol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 4)]-O-β-d-glucopyranoside (2) and two known compounds, (3β, 12β, 25R)-spirost-5-ene-3,12-diol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 4)]-O-β-d-glucopyranoside, (3), (1α, 3β, 25R)-spirost-5-ene-2-diol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl(1 → 4)]-O-β-d-glucopyranoside (4). The four compounds showed potent protective effect against anoxia in the anoxic PC12 cells assay, among which compounds 1 and 2 were the most active. To our knowledge, this is the first study to report the steroidal saponins in the plant S. uncinata and demonstrate their protective effect against anoxia in PC12 cell assay.     

Polyacetylenes and anti-hepatitis B virus active constituents from Artemisia capillaris

Three new polyacetylenes, 8-(Z)-decene-4, 6-diyne-1, 3, 10-triol (1), 1, 3S, 8S-trihydroxydec-9-en-4, 6-yne (2), 3S, 8S-dihydroxydec-9-en-4, 6-yne 1-O-β -D-glucopyranoside (3), and one new glucosyl caffeoate, 1-O-ethyl-6-O-caffeoyl-β -D-glucopyranose (4), together with 34 known compounds were isolated from Artemisia capillaris. The structures of the new compounds were determined by extensive spectroscopic analyses including 1D and 2D NMR, HRESIMS, [α]_D and CD experiments. Among them, 19 compounds showed activity inhibiting HBsAg secretion; 20 compounds showed activity inhibiting HBeAg secretion; and 25 compounds possessed inhibitory activity against HBV DNA replication according to our anti-HBV assay on HepG 2.2.15 cell line in vitro. The most active compound 12 could inhibit not only the secretions of HBsAg and HBeAg, but also HBV DNA replication with IC₅₀ values of 15.02 μM (SI = 111.3), 9.00 μM (SI = 185.9) and 12.01 μM (SI = 139.2).     

Sibiricasaponins A–E,five new triterpenoid saponins from the aerial parts of Polygala sibirica L.

Five new triterpenoid saponins, named as sibiricasaponins A–E (1–5), were isolated and identified from the aerial parts of Polygala sibirica L., together with nine known triterpenoid saponins (6–14). The chemical structures of the five new triterpenoid saponins (1–5) were elucidated as 3β,19α-dihydroxyurso-12-ene-23,28-dioic acid 3-O-β-d-glucuronopyranoside (1), pomolic acid 3-O-(3-O-sulfo)-α-l-arabinopyranoside (2), pomolic acid 3-O-(4-O-sulfo)-β-d-xylopyranoside (3), pomolic acid 3-O-(2-O-acetyl-3-O-sulfo)-α-l-arabinopyranoside (4), and 3-O-β-d-glucopyranosyl medicagenic acid 28-O-β-d-galactopyranosyl (1 → 4)-β-d-xylopyranosyl (1 → 4)-α-l-rhamnopyranosyl (1 → 2)-(4-O-acetyl)-[β-d-apiofuranosyl (1 → 3)]-β-d-fucopyranosyl ester (5), respectively, on the basis of spectroscopic data and physicochemical evidences. These isolated compounds (1–14) were evaluated for their anti-ischemic effects on oxygen/glucose deprivation (OGD) model in vitro, and only compound 7 showed a weak anti-ischemia effect, with EC₅₀ value of 46.7 μM.     

Phenylethanoid glycosides from the stems of Callicarpa peii (hemostatic drug)

Two new trisaccharide intermediates of phenylethanoid glycosides, peiioside A₁/A₂ (1a/1b) and peiioside B (2), were isolated from the n-BuOH fraction of MeOH extract of the stems of Callicarpa peii H.T. Chang, together with five biogenetic relevant known compounds 3–7. The structures of compounds 1 and 2 were elucidated by extensive spectroscopic methods (especially 2D-NMR techniques) and acid-catalyzed hydrolysis as O-α-l-rhamnopyranosyl-(1″ → 3′)-O-[β-d-apiofuranosyl-(1‴ → 6′)] -4′-O-[(E)-caffeoyl]-d-glucopyranoside] (1a/1b), 3,4-dihydroxy-β-phenylethoxy-O-[β-d-apiofuranosyl-(1‴ → 6′)-α-l-rhamnopyranosyl-(1″ → 3′)-O-β-d-glucopyranoside] (2), respectively. On the basis of the isolated compounds, a presumable biogenetic pathway of the biologically interesting phenylethanoid glycosides about forsythoside B (3) and acteoside (4) isolated from this species was proposed. Isolation of five related intermediates (1–2, 5–7) provided further support for the biogenetic path. This is the first report about phytochemical research on C. peii and the biogenetic hypothesis of forsythoside B and acteoside.     

Glycosylsphingolipids from Euonymus japonicus Thunb

The stem bark of Euonymus japonicus Thunb. led to the isolation of three new glycosylsphingolipids (1–3), 1-O-[-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranosyl]-(2S,3R,9E)-2-N-[(2R)-hydroxystearoyl]-octadecasphinga-9-ene (euojaposphingoside A, 1), 1-O-[β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl]-(2S,3R,4R,11E)-2-N-[(2R)-hydroxydocasanoyl]-octadecasphinga-11-ene (euojaposphingoside B, 2), 1-O-[β-D-glucopyranosyl]-2′-O-[β-D-glucopyranosyl]-(2S,3R,4R,11E)-2-N-[(2R)-hydroxytetracosanoyl]-octadecasphinga-11-ene (euojaposphingoside C, 3) along with three known glycosylsphingolipids (4–6), 1-O-[β-D-glucopyranosyl]-(2S,3R,9E)-3-hydroxymethyl-2-N-[(2R)-hydroxynonacosanoyl)-tridecasphinga-9-ene (4), 1-O-[β-D-glucopyranosyl]-(2S,3R,9E,12E)-2-N-[(2R)-hydroxytetracosanoyl] octadecasphinga-9,12–diene (5), 1-O-[β-D-glucopyranosyl]-(2S,3R,5R,9E)-2-N-[tridecanoyl] nonacosasphinga-9-ene (6), lupeol (7), stigmasterol (8), sitosterol (β and α) (9,10) and β-carotene (11). The structure of all the compounds was achieved by spectroscopic and chemical data analysis. The antiplasmodial, antileismanial and cytotoxic activity of all compounds was tested.     

Two novel saponins of 20, 26-epoxy derivatives of pseudojujubogenin from the seeds of Hovenia trichocarpa

Two new saponins of 20, 26-epoxy derivatives of pseudojujubogenin, hoduloside XI (1) and hoduloside XII (2) were isolated from the seeds of Hovenia trichocarpa. The structures of the new compounds were established by extensive NMR experiments and chemical methods. Hoduloside XI was confirmed to be 3-O-{β-d-glucopyranosyl(1 → 3)-[β-d-xylopyranosyl(1 → 2)]-α-l-arabinopyranosyl}-20, 26-epoxypseudojujubogenin. Hoduloside XII was identified as 3-O-{β-d-xylopyranose(1 → 2)glucopyranosyl(1 → 3)[rhamnopyranose(1 → 2)]β-d-glucopyranosyl}-20, 26-epoxypseudojujubogenin. The in vitro cytotoxic activity of compounds 1 and 2 was assayed. They displayed inhibitive activities against human cancer cell lines HL60 and K562.     

Sesquiterpene lactones from Sonchus arvensis L. and their antibacterial activity against Streptococcus mutans ATCC 25175

Two new sesquiterpene lactones, 1β-sulfate-5α, 6βH-eudesma-3-en-12, 6α-olide (1) and 1β-(p-hydroxyphenyl acetyl)-15-O-β-d-glucopyranosyl-5α, 6βH-eudesma-3-en-12, 6α-olide (2) were isolated from Sonchus arvensis L. (Asteraceae), together with eight known compounds. Their structures were elucidated through spectroscopic and chemical methods. They were evaluated for antibacterial activity. Among them, compounds 1 and 7 exhibited antibacterial activity against oral pathogen Streptococcus mutans ATCC 25175 with MIC values of 15.6 and 62.5 µg/ml, respectively.     

Triterpenoids of sour jujube show pronounced inhibitory effect on human tumor cells and antioxidant activity

Sour jujube is a common fruit and traditional medicine in China. Bioactivity-guided fractionation of sour jujube was used to determine the chemical identity of potent antiproliferative and antioxidant constituents. Four novel ursane-type triterpenoids, together with 8 known were isolated and identified. The new triterpenoids were elucidated to be 2α,3β,13β,23-tetrahydroxy-urs-11-en-28-oic acid (3), 2α,3β-dihydroxy-urs-20(30)-en-28-oic acid (9), 2α,3β,28-trihydroxy-urs-20(30)-ene (10), and 3β,12β,13β-trihydroxy-ursan-28-oic acid (11). Among the triterpenoids isolated, 2α,3β,19α-trihydroxy-urs-12-en-28-oic acid (7), 9 and 10 showed high potent inhibitory activity toward the proliferation of HepG2 cells, which the IC₅₀ values were lower than 5 μM. Compounds 9 and 10 also exhibited pronounced activity against MCF-7 cells, with IC₅₀ value of 0.8 ± 0.03 and 1.5 ± 0.1 μM, respectively. Compound 10 showed high antioxidant activity with an EC₅₀ of 0.8 ± 0.02 μM, which was 18.9 times higher than ascorbic acid in antioxidant capacity.     

Pregnane alkaloids from Sarcococca hookeriana var. digyna

Fourteen pregnane-type steroidal alkaloids were isolated from the ethanolic extracts of whole Sarcococca hookeriana var. digyna plants. Their structures were elucidated on the basis of spectral data. Three of them were identified as new steroidal alkaloids: (S)-20-(N,N-dimethylamino)-16α,17α-epoxy-3β-methoxy-pregn-5-ene (1), (20S)-20-(N,N-dimethylamino)-3β-tigloylamino-5α-pregn-11β-ol (2), and (20S)-2α,4β-bis(acetoxy)-20-(N,N-dimethylamino)-3β-tigloylamino-5α-pregnane (3). Some of the isolated compounds showed estrogen biosynthesis-promoting effects in human ovarian granulosa-like KGN cells. The EC₅₀ values for the most effective compounds, vagnine B (6) and funtumafrine C (12), were 71 μM and 67 μM, respectively.     

Desmodeleganine,a new alkaloid from the leaves of Desmodium elegans as a potential monoamine oxidase inhibitor

Desmodeleganine (1), a new potential monoamine oxidase inhibitor, along with three known alkaloids, bufotenin (2), hydroxy-N, N-dimethyltryptamine N¹²-oxide (3), 2-(5-methoxy-1H-indol-3-yl)-N, and N-dimethylethylamine (4) were isolated from the leaves of Desmodium elegans. Their structures were elucidated by IR, MS, 1D and 2D NMR spectra. 1 showed strong monoamine oxidase inhibitory activity with IC₅₀ value of 13.92 ± 1.5 μM, when the IC₅₀ value of iproniazid as a standard was 6.5 ± 0.5 μM. The molecular modeling was also performed to explore the binding mode of compounds 1, 2 at the active site of MAO-A and MAO-B.     

Purification,structural elucidation and antitumor activity of a novel mannogalactoglucan from the fruiting bodies of Lentinus edodes

A mannogalactoglucan, named LE-MGG, was isolated from the basidiocarps of Lentinus edodes by hot water-extraction, ethanol precipitation anion exchange chromatography, and further purified by gel-permeation chromatography (GPC). Its structural features were investigated by high performance liquid chromatography (HPLC), high performance gel-permeation chromatography (HPGPC), methylation analysis, periodate oxidation-Smith degradation, and by IR and NMR spectroscopy, including two-dimensional (2D) NMR. HPLC analysis revealed that LE-MGG contained mannose–galactose–glucose in the molar ratio of 10:18:72. GPC and HPGPC showed that LE-MGG was a homogeneous fraction (d = 1.34) and its molecular weight was estimated to be 18 kDa. Chemical and spectroscopic studies indicated that LE-MGG consists of (1 → 6)-, (1 → 4)- and (1 → 3)-linked β-d-glucopyranosyl residues, (1 → 6)-linked α-d-galactopyranosyl residues, (1 → 3,6)- and (1 → 2,4)-linked α-d-mannopyranosyl residues and terminal residues of β-d-glucopyranosyl. Cytotoxicity assay showed that LE-MGG presented higher antitumor activities against S-180 cell with a dose-dependent manner, and exhibited lower cytotoxicity to carcinoma HCT-116 and HT-29 cells. Our studies showed also that LE-MGG presented antitumor bioactivities on Sarcoma 180 solid tumor cell implanted in Kunming mice. This finding suggests that mannogalactoglucan should be explored as potential antitumor agents and could be potentially applied as a natural antitumor drug.     

Two new furostanol saponins from Tribulus terrestris L.

Two new furostanol glycosides, named tribufurosides I (1) J (2), were isolated from the fruits of Tribulus terrestris L. by a combination of chemical and spectroscopic methods. Its structures were established as 26-O-β-d-glucopyranosyl-(25S)-5α-furost-12-one-2α,3β,22α,26-tetraol-3-O-β-d-glucopyranosyl (1 → 2)-β-d-glucopyranosyl (1 → 4)-β-d-galactopyranoside (1) and 26-O-β-d-glucopyranosyl-(25R)-5α-furost-20(22)-en-12-one-2α,3β,26-triol-3-O-β-d-glucopyranosyl (1 → 4)-β-d-galactopyranoside (2).     

Japonicasins A and B,two new isoprenylated flavanones from Sophora japonica

Two new flavanones with a C₁₅ isoprenoid group, japonicasins A and B (1 and 2), were isolated from the leaves of Sophora japonica. This is the first report on the presence of the (2E,7E)-6-isopropyl-3,9-dimethyldeca-2,7,9-trien-1-yl group (C₁₅ isoprenoid group) in isoprenylated flavonoids. Their structures were determined by spectroscopic methods, including UV, IR, 1D and 2D NMR, HRESIMS, and CD experiments. In addition, the antioxidant activities of compounds 1 and 2 were determined through DPPH radical scavenging assays. They exhibited potential antioxidant activities, with IC₅₀ values of 35.1 ± 0.8 μM and 88.7 ± 1.1 μM for compounds 1 and 2, respectively.     

Triterpenoids from the fruits of Azadirachta indica (Meliaceae)

Four new triterpenoids, indicalilacols A-D (1–4), were isolated from the MeOH extract of the fruits of Azadirachta indica, including a new 19(10 → 9β)abeo-tirucallane derivative, two new tirucallane-type triterpenoids, and a new euphane-type triterpenoid, along with three known tirucallane-type triterpenoids. Their structures were elucidated on the basis of spectroscopic analyses. The absolute configuration of 2 was elucidated by the chemical conversion of 2 into 21-oxo-melianodiol 24,25-acetonide. Compounds 2, 6–8 exhibited moderate cytotoxicity against three human cancer cell lines, including multidrug-resistant (MDR) cancer cells (KB-C2). Although compound 5 was not cytotoxic against any of the tested cancer cell lines, 5 showed cytotoxicity against KB-C2 cells in the presence of 2.5 μM colchicine, suggesting that 5 might have an MDR-reversal effect.     

Protection of chronic renal failure by a polysaccharide from Cordyceps sinensis

A water-soluble polysaccharide (CPS-2), isolated from the cultured Cordyceps sinensis, was obtained by hot-water extraction, anion-exchange and gel permeation chromatography. Its structural characteristics were investigated by PMP pre-column derivation, periodate oxidation, methylation analysis, FTIR and NMR spectroscopy. CPS-2 was found to be mostly of α-(1 → 4)-d-glucose and α-(1 → 3)-D-mannose, branched with α-(1 → 4,6)-d-glucose every twelve residues on average. CPS-2 had a molecular weight of 4.39 × 10⁴ Da. The protective effect of CPS-2 on the model of chronic renal failure was established by fulgerizing kidney. The changes in blood urea nitrogen and serum creatinine revealed that CPS-2 could significantly relieve renal failure caused by fulgerizing kidney.