Flavonoids, coumarins and triterpenes from the aerial parts of Cnidoscolus texanus

Phytochemical investigation on Cnidoscolus texanus led to the isolation of 26 compounds, which included 15 flavonoids (1-15), three coumarins (16-18), three coumaric acid derivatives (19-21), four triterpenoids (22-25), and one phytosterol (26). Among them, aromadendrin 7-O-(4'-O-P-E-coumaroyl-beta-glucopyranoside) (1), aromadendrin 7-O-(3',6'-di-O-P-E-coumaroyl-beta-glucopyranoside) (2), and naringenin 7-O-(4'-O-P-Z-coumaroyl-beta-glucopyranoside) (3) are new compounds. Their structures were determined by spectroscopic and chemical methods. All flavonoids were found to be inactive against DNA topoisomerase I.     

Sterols, triterpenes and biflavonoids of Viburnum jucundum and cytotoxic activity of ursolic acid

The triterpenes ursolic acid (1), 27-p-Z-coumaroyloxyursolic acid (2), 27-p-E-coumaroyloxyursolic acid, alpha-amyrine-3-palmitate and lupeol-3-palmitate were isolated through a bioactivity-guided fractionation from the acetonic extract of the aerial parts of Viburnum jucundum Morton in addition to amentoflavone, an epimeric mixture at C-2 of 2,3-dihydroamentoflavone, beta-sitosterol and beta-sitosteryl glucopyranoside. Ursolic acid (1) was the only constituent that exhibited cytotoxic activity toward three human cancer cell lines in culture. This is the first phytochemical and cytotoxic analysis performed to this plant species.     

Toxicity of flavoglaucin from Aspergillus chevalieri in rabbits

Female rabbits were injected intraperitoneally (i.p.) with purified flavoglaucin from Aspergillus chevalieri. After 2 h the rabbits were bled and the livers removed for enzyme assays. No changes were found for plasma lactate dehydrogenase (LDH) and its isozymes or liver transketolase (TK) activities. A small but not statistically significant increase was found in plasma glutamate pyruvate transaminase activity. A highly significant increase in plasma glutamic oxaloacetate transaminase activity was observed along with an increase in liver LDH which was, however, not quite significant. The liver also showed some histological evidence of hepatic damage.     

Toxicity of echinulin from Aspergillus chevalieri in rabbits

Rabbits were injected intraperitoneally with purified echinulin, a product of Aspergillus chevalieri. After 2 h, the rabbits were bled and enzyme analyses were carried out on the supernates of liver homogenates and citrated plasma. Elevated levels of total plasma lactate dehydrogenase, cardiac derived isozyme, glutamic-oxaloacetic and glutamic-pyruvic transaminase activities in animals receiving toxin were observed. These levels were statistically significant compared to the vehicle control. A significant increase in liver lactate dehydrogenase of toxin-treated rabbits was also observed. Light-microscopic examination of lung and liver showed a significant degree of damage. The increase in plasma enzyme levels is indicative of damage to these organs.     

Antitumor triterpenes from medicinal plants

Thirteen kinds of naturally occurring or derivatised triterpenes, reported to have an antitumoral property, were reinvestigated on the basis of their direct cytotoxicity or the inhibitory activity on cell growth against five kinds of cultured human tumor cells,i. e., A-549, SK-OV-3, SK-MEL-2, XF498 and HCT15,in vitro. Ursonic acidIII, betulinic acidVIII, betulonic acidX and glycyrrhetinic acidXI were exhibited a marked inhibition on cell growth.     

Cytotoxic triterpenes from Ligulariopsis shichuana

Five olean-12-ene triterpenes (1-5) were isolated from the whole plant of Ligulariopsis shichuana. Their structures were elucidated by spectroscopic methods, including IR, EIMS positive HRSIMS, 1DNMR, and 2DNMR. Among them, 16beta,28-dihydroxyolean-12-en-3-one (3), olean-12-en-3beta,6beta,16beta,28-tetraol (4), 6beta,16beta-dihydroxyolean-12-en-3-one (5) are new compounds. In addition, compounds 4 and 5 showed cytotoxic activities on human hepatomacells (SMMC-7721), human ovarian neoplasm cells (HO-8910) and human hepatocytes cells (LO2).     

Dammarane triterpenes from Ligustrum lucidum

Two new dammarane triterpenes 3beta-acetyl-20S,24R-dammarane-25-ene-24-hydroperoxy-20-ol (1), 20S,24R-dammarane-25-ene-24-hydroperoxy-3beta,20-diol (2), as well as three known dammarane triterpenes, 3beta-acetyl-20S,25-epoxydammarane-24alpha-ol (3), 20S,25-epoxydammarane-3beta,24alpha-diol (4), 20S-dammarane-23-ene-3beta,20,25-triol (5) were isolated from the fruits of Ligustrum lucidum. Compounds 3-5 were isolated from the fruits of L. lucidum for the first time. Their structures were elucidated by spectroscopic methods.     

Oleanane-type triterpenes from Ludwigia octovalvis

Two new oleanane-type triterpenes, (23Z)-feruloylhederagenin (1) and (23E)-feruloylhederagenin (2), together with two known oleanane-type triterpenes, β-amyrin acetate and β-amyrin palmitate, have been isolated from the whole plant of Ludwigia octovalvis. The structures of 1 and 2 were characterised on the basis of spectral evidence.     

Bioactive coumarins from Boenninghausenia sessilicarpa

Bioassay guided fractionation of Boenninghausenia sessilicarpa (Rutaceae) resulted in the isolation of a new dimeric coumarin glucoside 9'-methoxyl rutarensin (1) and a cytotoxic compound rutamarin (4), as well as an antivirus component leptodactylone (8), together with six known coumarins. Their structures were elucidated by 1D- and 2D NMR spectroscopy and ESI-MS analyses, respectively. Rutamarin (4) showed significant inhibitory activities against A-549, Bel-7402, HepG-2 and HCT-8 tumour cell lines with IC₅₀s of 1.318, 2.082, 2.306 and 2.497 μg/ml. In addition, leptodactylone (8) showed potent protective activity on cells infected by SARS-CoV with ratio of 60% at 100 μg/ml.     

Cytotoxic coumarins from Mammea harmandii

Two new naturally occurring coumarins, isomesuol (1) and mammearin A (2), together with nine known Mammea coumarins 3-11 were isolated from the EtOAc extract of the leaves and twigs of Mammea harmandii. Coumarins 1, 3 and 4 showed cytotoxicity against a panel of mammalian cancer cell lines. Their structures were determined by spectroscopic methods. The assignments of 13C-NMR signals of isomesuol (1), which was isolated for the first time as a natural product, have been revised.     

Cytotoxic lanostanoid triterpenes from Ganoderma lucidum

Two new lanostanoid triterpenes, 23S-hydroxy-3,7,11,15-tetraoxo-lanost-8,24E-diene-26-oic acid (1), and 12beta-acetoxy-3beta-hydroxy-7,11,15,23-tetraoxo-lanost-8,20E-diene-26-oic acid (16), together with 17 known compounds, were isolated from the fruit bodies of Ganoderma lucidum. Their structures were established by spectroscopic methods, especially 2D-NMR and MS analyses and by comparison with literature data. The cytotoxic assay of the above compounds against p388, Hela, BEL-7402, and SGC-7901 human cancer cell lines showed their cytotoxicity with the IC50 values in the range of 8-25 microm.     

New coumarins from Pterocaulon polystachyum

Aerial parts of Pterocaulon polystachyum from Chaco province, Argentina, afforded the known coumarins ayapin, isoscopoletin, prenyletin, prenyletin methyl ether, virgatenol, obtusinin, 5-methoxy-6,7-methylenedioxycoumarin, 5-(3,3-dimethylallyloxy)-6,7-methylenedioxycoumarin, 5-(2',3'-dihydroxy-3-methylbutanoxy)-6,7-methylenedioxycoumarin, haplopinol methyl ether, 6-(1,1-dimethyl-2-propenyl)-7-hydroxycoumarin and demethylnieshoutin; the last two are new as natural products while the five new coumarins from the collection were isovirgatenol, 3'-deoxyobtusinin, 6-methoxy-7-(2'-hydroxyethoxy)-coumarin, 5-(2'-hydroxyethoxy)-6,7-methylenedioxycoumarin and a substance tentatively identified as 5-hydroxy-6,7-methylenedioxy-8-(3,3-dimethylallyl)-coumarin.     

Anti-inflammatory coumarins from Paramignya trimera

Context: Paramignya trimera (Oliv.) Burkill (Rutaceae) has been used to treat liver diseases and cancer. However, the anti-inflammatory effects of this medicinal plant and its components have not been elucidated.

Objective: This study investigated chemical constituents of the P. trimera stems and evaluated anti-inflammatory effects of isolated compounds.

Materials and methods: Cytotoxicity of isolated compounds (5–40?μM) toward BV2 cells was tested using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) for 24?h. Inhibitory effects of isolated compounds (5-40?μM) on nitrite and PGE₂ concentrations were determined using Griess reaction and PGE₂ ELISA kit, respectively (pretreated with the compounds for 3?h and then stimulated for 18?h with LPS). Inhibitory effects of compounds (5-40?μM) on iNOS and COX-2 protein expression were evaluated by Western blot analysis (pretreated with the compounds for 3?h and then stimulated for 24?h with LPS).

Results: Seven coumarins were isolated and identified as: ostruthin (1), ninhvanin (2), 8-geranyl-7-hydroxycoumarin (3), 6-(6′,7′-dihydroxy-3′,7′-dimethylocta-2′-enyl)-7-hydroxycoumarin (4), 6-(7-hydroperoxy-3,7-dimethylocta-2,5-dienyl)-7-hydroxycoumarin (5), 6-(2-hydroxyethyl)-2,2-dimethyl-2H-1-benzopyran (6), and luvangetin (7). Compounds 1–4 and 7 inhibited NO and PGE₂ production in LPS-stimulated BV2 cells, with IC₅₀ values ranging from 9.8 to 46.8 and from 9.4 to 52.8?μM, respectively. Ostruthin (1) and ninhvanin (2) were shown to suppress LPS-induced iNOS and COX-2 protein expression.

Discussion and conclusion: The present study provides a scientific rationale for the use of P. trimera in the prevention and treatment of neuroinflammatory diseases. Ostruthin and ninhvanin might have potential therapeutic effects and should be considered for further development as new anti-neuroinflammatory agents.     

Anti-inflammatory triterpenes from Pistacia terebinthus galls

From the galls of Pistacia terebinthus we obtained an extract that proved to be effective against chronic and acute inflammation. Now we report on the isolation and identification of three triterpenes: two tirucallane-type lanostanoids and one oleanane, which we have identified as masticadienonic acid (1), masticadienolic acid (2), and morolic acid (3), respectively. All of them showed effectiveness on the mouse ear inflammation induced by repeated applications of 12-O-tetradecanoylphorbol 13-acetate and on the phospholipase A2-induced foot paw edema. The pharmacological activity of the compounds was ratified by a histological study of the ear samples. In addition, they inhibited leukotriene B4 production in rat polymorphonuclear leukocytes stimulated with calcium ionophore A 23187.     

Two new triterpenes from Lysimachia foenum-graecum

Two new oleane-type triterpene saponins, lysimachiagenoside E (1) and lysimachiagenoside F (2), were isolated from the aerial parts of Lysimachia foenum-graecum Hance. The structures were elucidated on the basis of 1D and 2D NMR techniques, including ¹H–¹H COSY, HMQC, HMBC, TOCSY, ROESY experiments as well as chemical methods.     

Cytotoxic lanostanoid triterpenes from Ganoderma lucidum

Two new lanostanoid triterpenes, 23S-hydroxy-3,7,11,15-tetraoxo-lanost-8,24E-diene-26-oic acid (1), and 12beta-acetoxy-3beta-hydroxy-7,11,15,23-tetraoxo-lanost-8,20E-diene-26-oic acid (16), together with 17 known compounds, were isolated from the fruit bodies of Ganoderma lucidum. Their structures were established by spectroscopic methods, especially 2D-NMR and MS analyses and by comparison with literature data. The cytotoxic assay of the above compounds against p388, Hela, BEL-7402, and SGC-7901 human cancer cell lines showed their cytotoxicity with the IC(50) values in the range of 8-25 mum.     

Two new triterpenes from Euphorbia alatavica

A phytochemical investigation on Euphorbia alatavica Boiss resulted in the isolation of nine compounds, including two new ones, alatavolide and alatavoic acid (1–2). Chemical structures of these compounds were established on the basis of 1D, 2D NMR, and HR-MS techniques, and by comparison with data reported in the literature. Compounds 1, 2, 4, 6, 8, and 9 were screened for cytotoxicity using the MTT assay. Among these compounds, the new compound 2 showed moderate cytotoxicity against Hela, MCF-7 and A549 cell lines (IC₅₀ values of 16.4 ± 3.2, 14.5 ± 2.8, 22.3 ± 3.1 μM, respectively), while the known compound 8 exhibited the most potent cytotoxicity with the IC₅₀ values of 6.5 ± 3.1, 1.9 ± 0.9, 8.6 ± 3.5 μM, respectively.     

Cytotoxic lanostanoid triterpenes from Ganoderma lucidum

Two new lanostanoid triterpenes, 23S-hydroxy-3,7,11,15-tetraoxo-lanost-8,24E-diene-26-oic acid (1), and 12β-acetoxy-3β-hydroxy-7,11,15,23-tetraoxo-lanost-8,20E-diene-26-oic acid (16), together with 17 known compounds, were isolated from the fruit bodies of Ganoderma lucidum. Their structures were established by spectroscopic methods, especially 2D-NMR and MS analyses and by comparison with literature data. The cytotoxic assay of the above compounds against p388, Hela, BEL-7402, and SGC-7901 human cancer cell lines showed their cytotoxicity with the IC₅₀ values in the range of 8–25 μm.