New phenanthrene glycosides from Dendrobium denneanum and their cytotoxic activity

Five new phenanthrene glycosides, denneanosides A–E (1–5), and one new 9,10-dihydrophenanthrene glycoside, denneanoside F (6) were isolated from the stem of Dendrobium denneanum. The chemical structures of the new compounds were established on the basis of extensive spectroscopic data. The isolated compounds were evaluated for their in vitro cytotoxic activity against SNU387 hepatocellular carcinoma cell line. Compounds 1–3 showed moderate cytotoxic activities while compounds 4–6 showed weak activities.     

Five new cucurbitane triterpenoids with cytotoxic activity from Hemsleya jinfushanensis

Five new cucurbitane triterpenoids (hemslepenside B–E (1–3 and 5)), one new cucurbitane (16,25-O-diacetyl-cucurbitane F (4)), and six analogues (6–11) were isolated from the roots of Hemsleya jinfushanensis. The structures of 1–5 were elucidated using infrared absorption spectroscopy (IR), high resolution electrospray ionization mass spectrometry (HR-ESI-MS), and nuclear magnetic resonance spectroscopy (NMR). These five new compounds exhibited cytotoxic effects against lung adenocarcinoma (H460), colon cancer (SW620) and human prostate cancer cells (DU145), and compound 4 showed significant cytotoxic activity, with IC₅₀ values of 0.046, 0.18 and 0.87 μg/mL. This finding suggests that cucurbitane triterpenoids isolated from H. jinfushanensis should be studied further as potential anti-cancer drugs.     

New glycosides from Tetracentron sinense and their cytotoxic activity

One novel neolignan (tetracentronsine; 1), one new indole alkaloid (=3-(2-hydroxyethyl)-1H-indole-5-O-beta-D-glucopyranoside; 2), and two new phenol derivatives, 3-{2-[(beta-glucopyranosyl)oxy]-4,5-(methylenedioxy)phenyl}propanoic acid (3) and methyl 3-{2-[(beta-glucopyranosyl)oxy]-4,5-(methylenedioxy)phenyl}propanoate (4), together with six known compounds were isolated from the stem bark of Tetracentron sinense. Their structures were determined by spectral analysis, including 1D- and 2D-NMR, and MS analyses. These compounds were tested for their cytotoxic activity against human leukaemia cells in vitro. Among them, compound 2, (E)-3-(4-hydroxyphenyl)-N-[2-(4-hydroxyphenyl)ethyl]prop-2-enamide (5), and maslinic acid (6) showed significant inhibitory activities against human leukaemia cells CCRF-CEM and its multidrug-resistant sub-line, CEM/ADR5000, with IC50 values in a range of 7.1 to 29.7 microM.     

Two tirucallane derivatives from Paramignya scandens and their cytotoxic activity

Various chromatographic separations of the methanolic extract of Paramignya scandens stem and leaves resulted in the isolation of two new tirucallane derivatives, paramignyols A and B (1 and 2). Their structures were established by HR-ESI-MS, 1D and 2D NMR experiments, as well as, comparison with literature data. Compounds 1 and 2 showed significant cytotoxic activity (IC₅₀s ∼ 3.55–10.50 μM) on four tested human cancer cell lines: KB (epidermoid carcinoma), SK-Mel-2 (melanoma), LU-1 (lung adenocarcinoma), and MCF7 (breast cancer). This is the first report on chemical constituents and biological activities of P. scandens.     

Two new polyhydroxylated steroidal glycosides from Paris polyphylla var. yunnanensis

Chemical investigation of Paris polyphylla smith var. yunnanensis afforded two new polyhydroxylated steroidal glycosides, named Parisyunnanosides K and L (1–2), together with nine known ones. The chemical structures of the new compounds were elucidated by 1D, 2D NMR and HR-ESI-MS techniques, together with chemical methods. Parisyunnanosides K and L (1–2) are rare C₂₇ steroidal glycosides with two double bonds located at C-5, 6 and C-25, 26 of the aglycone, respectively. The cytotoxic activities of the isolated compounds were evaluated against Caco-2 cells by CCK-8 assay. Among them, compounds 5–11 exhibited potent cytotoxic activity with IC₅₀ values ranging from 1.10 to 14.14 μM compared with the positive control oxaliplatin (1.38 μM).     

Three new diterpenes with cytotoxic activity from the roots of Euphorbia ebracteolata Hayata

From the roots of Euphorbia ebracteolata Hayata, three new diterpenes, Ebracteolatas A–C, based on the rosane (1–2) and lathyrane (3) skeleton, were isolated together with four known ones (4–7). Their structures and relative configurations were elucidated on the basis of spectroscopic methods, especially 2D NMR techniques. Compounds 1, 6, and 7 exhibited moderate cytotoxic effects against five cancer cell lines.     

Two new flavonol derivatives from the whole plants of Centella asiatica and their cytotoxic activities

Centella asiatica is well known as an important medicinal plant because of its various pharmacological effects. However, most investigations on C. asiatica focused on the pharmacological activity of its extract or asiatic acid. In the present work, we aimed to explore the bioactive compounds of the whole plants of C. asiatica. As a result, seven compounds including two new flavonol derivates named 4′-hydroxyl-7-methoxyl-6-prenyl-3-O-trans-p-coumaroyl-flavonol (1) and (2R,3R,2″S)-3-furanoyl-brosimacutin E (2), and five known compounds (3-7) were isolated. Their chemical structures were elucidated on the basis of spectroscopic analyses. All the isolates were evaluated for in vitro cytotoxic effects on four human cancer cells including A549, HepG2, SGC-7901 and MCF-7. Among them, compounds 1 and 2 exhibited higher cytotoxic activities on HepG2 and SGC-7901 cells compared with 3-7. And compound 2 showed potential cytotoxic activities on HepG2 and SGC-7901 cells with IC₅₀ values of 4.52 and 7.03 μM, respectively.     

Pregnane alkaloids from Sarcococca ruscifolia and their cytotoxic activity

Six pregnane alkaloids were isolated from the root of Sarcococca ruscifolia. The structures of three new alkaloids, namely, sarcorucinine E–G (1–3), were elucidated using spectroscopic methods, while three known alkaloids, namely, epipachysamine D, pachysamine M, and sarcovagine D, were identified by comparing their spectral data with those of the compounds reported earlier. All compounds were evaluated for their inhibitory activities against multiple types of cancer cells.     

Four new steroidal glycosides from Solanum torvum and their cytotoxic activities

Two novel C-22 steroidal lactone saponins, namely solanolactosides A, B (1, 2) and two new spirostanol glycosides, namely torvosides M, N (3, 4) were isolated from ethanol extract of aerial parts of Solanum torvum. Their structures were characterized as solanolide 6-O-[α-l-rhamnopyranosyl-(1 → 3)-O-β-d-quinovopyranoside] (1), solanolide 6-O-[β-d-xylopyranosyl-(1 → 3)-O-β-d-quinovopyranoside] (2), yamogenin 3-O-[β-d-glucopyranosyl-(1 → 6)-O-β-d-glucopyranoside] (3) and neochlorogenin 3-O-[β-d-glucopyranosyl-(1 → 6)-O-β-d-glucopyranoside] (4) on the basis of spectroscopic analysis. The cytotoxicities of the saponins (1-4) were evaluated in vitro against a panel of human cancer cell lines. Compounds 3 and 4 showed significant cytotoxic activity with the cell lines.     

Terpenoids with cytotoxic activity from the branches and leaves of Pyrus pashia

Twenty terpenoids, including a new triterpenoid (1) and a new monoterpenoid (20), were isolated from the branches and leaves of Pyrus pashia. The structures of two new compounds were determined to be 2α, 3β, 27-trihydroxyolean-12-en-28-oic acid (1) and (4α)-3-(5,5-dimethyltetrahydrofuranyl)-1-buten-3-ol 3-O-β-d-glucopyranoside (20) on the basis of spectroscopic analysis (IR, HRESIMS, 1D and 2D NMR) and chemical method. Some of the isolated compounds were evaluated for their cytotoxic activity against a panel of human cancer cell lines by MTT assay, using cisplatin as a positive control. Compound 14 exhibited cytotoxic activities against A549 (IC₅₀ = 19.18 ± 4.26 μM), Hela (IC₅₀ = 12.56 ± 3.89 μM), SGC7901 (IC₅₀ = 10.48 ± 1.95 μM) and NHI-1975 (IC₅₀ = 7.38 ± 2.31 μM) cell lines as well as compound 12 displayed cytotoxic activities against A549 (IC₅₀ = 14.71 ± 1.47 μM) and Hela (IC₅₀ = 12.22 ± 1.88 μM) cell lines.     

Three new chlorinated phenolic glycosides from Przewalskia tangutica

Three new chlorinated phenolic glycosides, namely przewatangosides A-C (1-3), along with one known compound, globosumoside A (4), were isolated from the whole plants of Przewalskia tangutica. Their structures were unequivocally determined by extensive spectroscopic analysis and chemical method. The cytotoxic activities of the isolated phenolic glycosides (1-4) were evaluated against the five human cancer cell lines A549, MCF-7, SMMC-7721, HepG2 and HL-60. Przewatangoside A (1) exhibited weak cytotoxicity against SMMC-7721 with the IC₅₀ value of 38.1 μM. All the tested compounds were inactive (IC₅₀ > 50 μM) to the normal human hepatocyte cell line (L02).     

Two new quinic acid derivatives and one new lignan glycoside from Erycibe obtusifolia

Three new compounds, 4-{erythro-2-[3-(4-hydroxyl-3-methoxyphenyl)-3-O-β-d-glucopyranosyl-propan-1-ol]}-O-medioresinol (1), (7⿳E,9⿳E,1⿳R*,3⿳S*,5⿳R*,6⿳S*)-5-O-caffeoyl-3-O-dihydrophaseicoylquinic acid (2), and (7⿳E,9⿳E,1⿳R*,3⿳S*,5⿳R*,6⿳S*)-5-O-caffeoyl-4-O-dihydrophaseicoylquinic acid (3), were isolated from Chinese folk herb Erycibe obtusifolia together with six known compounds (4⿿9). Their structures were elucidated on the basis of comparisons of literatures and extensive spectroscopic analysis, including UV, IR, HRMS, and 1D and 2D NMR techniques. Further, the cytotoxicities of these compounds were evaluated against five cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780), but they were inactive against these tumor cell lines (IC₅₀ > 10 μmol/L).     

Three new cytotoxic sesquiterpenoids from Solanum lyratum

In our continuing effort to discover more new cytotoxic sesquiterpenoid from Solanum lyratum collected from different districts of China, three new sesquiterpenoids, attributable to eudesmane-type (1, named solajiangxin D) and vetispirane-type (2–3, named solajiangxins E and 2-hydroxysolajiangxin E), respectively, were isolated. Their structures were elucidated on the basis of integrated spectroscopic techniques, mainly HR-FABMS, 1D and 2D NMR (¹H–¹H COSY, HMQC, HMBC and ROESY). In vitro, compounds 1–3 were found to show significant cytotoxicities against three human cancer lines (P-388, HONE-1, and HT-29), and gave ED₅₀ values in the range 2.1–3.7 μg/ml.     

Three new sesquiterpenoids from Solanum septemlobum with cytotoxic activities

Three new sesquiterpenoids, attributable to eudesmane-related (1–2, named septemlobins A–B) and vetispirane-type (3, named septemlobin C), respectively, were isolated from the whole plant of Solanum septemlobum. Their structures were elucidated on the basis of integrated spectroscopic techniques. In vitro, compounds 1–3 were found to show significant cytotoxicities against three cancer cell lines (P-388, HONE-1, and HT-29), and gave IC₅₀ values in the range 3.8–7.5 μM.     

Steroidal glycosides from the underground parts of Trillium erectum and their cytotoxic activity

Six steroidal glycosides, along with 14 known compounds, were isolated from the underground parts of Trillium erectum L. (Liliaceae). The structures of 1-6 were determined on the basis of extensive spectroscopic analysis, including two-dimensional (2D) NMR data, and a few chemical transformations. The isolated compounds were evaluated for their cytotoxic activity against HL-60 human promyelocytic leukemia cells.     

New phenylpropanoids with cytotoxic activities from Drypetes hainanensis

Phytochemical investigation on Drypetes hainanensis has resulted in the isolation of three new phenylpropanoids, named drypetesins A–C (1–3). Their structures were elucidated by applying various spectroscopic techniques (NMR, UV, IR, MS, and CD). The antiproliferative activities of these compounds were evaluated in vitro against three cultured cancer cell lines. Those new isolates exhibited potent cytotoxic activities against human hepatoma (HepG2), human breast adenocarcinoma (MCF-7), and human lung carcinoma (A-549) cancer cell lines with IC₅₀ value range 5.6–14.8 μM.     

Two new cycloartane-type triterpenoids and one new flavanone from the leaves of Dasymaschalon dasymaschalum and their biological activity

Two new cycloartane-type triterpenoids, 3β-hydroxy-21-O-acetyl-24-methylenecycloartane (3) and 3β,21-dihydroxy-24,31-epoxy-24-methylenecycloartane (4), one new flavanone, 7-hydroxy-6,8-dimethoxyflavanone (5), two new natural products, 2-hydroxybenzyl benzoate (7) and 2-phenyl-2-acetoxyethyl benzoate (8), and ten known compounds, 3β-hydroxy-24-methylenecycloartane (1), 3β,21-dihydroxy-24-methylenecycloartane (2), desmosdumotin B (6), artabotrene (9), (?)-senepoxide (10), (+)-crotepoxide (11), (?)-1,6-desoxypipoxide (12), rotundol (13), cassipourol (14) and (+)-spathulenol (15) were isolated from the leaves of Dasymaschalon dasymaschalum. The structures of the new compounds were elucidated by spectroscopic analysis and of the known compounds by comparison of their physical, UV, IR, ¹H and ¹³C NMR data with those of published compounds. Antimycobacterial, antiplasmodial and cytotoxic activities of the isolates, except 8 and 10 were evaluated. Compounds 1, 4, 5, 11, 12 and 15 exhibited potent cytotoxic activities against human lung cancer cell lines (NCI-H187) with respective IC₅₀ values of 4.67, 7.82, 1.85, 6.33, 3.07 and 6.68 μg/mL.     

Argusides B and C, two new cytotoxic triterpene glycosides from the sea cucumber Bohadschia argus Jaeger

Two new triterpene glycosides, argusides B and C (1 and 2, resp.), have been isolated from the sea cucumber Bohadschia argus Jaeger collected in the South China Sea. Their structures have been established by spectral analysis (2D-NMR and ESI-MS) and chemical evidence. Compounds 1 and 2 both possess a holostane-type triterpene aglycone with a C(9)==C(11) bond and a OH group at C(12), but differ in their substituents at C(17) and the hexasaccharide moiety. The two glycosides exhibited significant cytotoxicities against four human tumor cell lines (A549, HCT-116, HepG2, and MCF-7). In comparison with the positive control V-16 (etoposide), 1 and 2 showed higher cytotoxicities to A549 and HCT-116 cell lines.     

Argusides D and E, two new cytotoxic triterpene glycosides from the sea cucumber Bohadschia argus Jaeger

Two new triterpene glycosides, argusides D and E (1 and 2, resp.), have been isolated from the sea cucumber Bohadschia argus Jaeger collected in the South China Sea. Their structures have been established by spectral analysis (ESI-MS, and 1D- and 2D-NMR) and chemical evidence. Compounds 1 and 2 both possess an holostane-type triterpene aglycone with a C(9)=C(11) bond, an OH group at C(12), and tetrasaccharide moieties, but differ in the side chains. The two glycosides exhibited significant cytotoxicities against four human tumor cell lines, A549, HCT-116, HepG2, and MCF-7.     

A new ceramide from Suillus luteus and its cytotoxic activity against human melanoma cells

A new phytosphingosine-type ceramide, suillumide (1), was isolated from the EtOH extract of the basidiomycete Suillus luteus (L.) S. F. Gray, along with ten known compounds: ergosta-4,6,8(14),22-tetraen-3-one, ergosterol, ergosterol peroxide, suillin, (E)-3,4,5-trimethoxycinnamic alcohol, 5 alpha,6 alpha-epoxyergosta-8,22-diene-3beta,7 beta-diol, (R)-1-palmitoylglycerol, ergosta-7,9(11),22-triene-3beta,5 alpha,6 beta-triol, cerevisterol, and 4-hydroxybenzoic acid. The structure of 1 was determined on the basis of spectroscopic and mass-spectrometric analyses, as well as by chemical methods. Compound 1 and its synthetic diacetyl derivative 2 were tested for their cytotoxic activities against the human melanoma cell line SK-MEL-1. Both drugs showed IC(50) values of ca. 10 microM after 72 h of exposure.