Ursane-type Triterpenoids Research Articles

A New Diterpenoid Glucoside and Two New Diterpenoids from the Fruit of Vitex agnus-castus

A new labdane-type diterpenoid glucoside and two new labdane-type diterpenoids were isolated from the fruit (chasteberry) of Vitex agnus-castus L. (Verbenaceae) along with 14 known compounds comprising seven labdane-type diterpenoids, one halimane-type diterpenoid, two oleanane-type triterpenoids, two ursane-type triterpenoids, one aromadendrane-type sesquiterpenoid, and one flavonoid. Their structures were characterized on the basis of spectroscopic data as well as chemical evidence. Furthermore, the antioxidative activities of the flavonoid were evaluated using five different analyses.

Triterpenoids from the Flowers of Salvia miltiorrhiza

AbstractA phytochemical investigation of the flowers of Salvia miltiorrhiza Bunge led to the isolation of two new oleanane‐ and ursane‐type triterpenoids, (3α)‐olean‐12‐ene‐3,23‐diol (1) and (3α)‐urs‐12‐ene‐3,23‐diol (2), as well as of four known triterpenoids. Their structures were elucidated on the basis of spectroscopic evidence, including 1D‐ and 2D‐NMR, HR‐MS, and the X‐ray analysis, and by comparison with literature data.

Betulin and ursolic acid synthetic derivatives as inhibitors of Papilloma virus

The synthesis of new betulin and ursolic acid derivatives and evaluation of their antiviral activity in vitro is reported. Betulin was modified at positions C-3, C-20 and C-28 to afford the derivatives with nicotinoyl-, methoxycynnamoyl-, alkyne and aminopropoxy-2-cyanoethyl-moieties. The two stage conversion of betulin to the new ursane-type triterpenoid by treatment of allobetulin with Ac2O–HClO4 is suggested. Cyanoethylation of ursonic acid oxime led to cyanoethyloximinoderivative. According to the results of antiviral screening against human papillomavirus type 11 the selectivity index for tested triterpenoids has a range from 10 to 35 with no cellular cytotoxicite, the most remarkable activity was found for 3β,28-di-O-nicotinoylbetulin. 3β,28-Dihydroxy-29-norlup-20(30)-yne was also active against HCV replicon (EC50 1.32; EC90 16.82; IC50 12.41; IC90 >20; SI50 9.4; SI90 >1.19). 28-O-Methoxycynnamoylbetulin was active against influenza type A virus (H1N1) (ЕС50 2; IC50 >200; SI >100).

Zygophylloside S, a New Triterpenoid Saponin from the Aerial Parts of Zygophyllum coccineum L.

Saponins are a vast group of glycosides with a wide range of biological activities [1]. They are believed to form the main constituents of many plant drugs and folk medicines [2]. Their pharmacological importance has motivated us to contribute to the study of Zygophyllum coccineum L., an Egyptian desert plant rich in saponins. The present work led to the isolation of one new ursane type triterpenoid saponin (1), 3-O-[α-L-arabinopyranosyl-(1→2)-β-D-glucopyranosyl] quinovic acid (zygophylloside S), in addition to eight known saponins, one flavonoid glycoside, and one sterol glycoside from the aerial parts of the plant. The structures were established mainly by 1D and 2D NMR techniques, in combination with IR and HRMS. The anti-microbial, anti-malarial, and anti-leishmanial activity of the isolated compounds are in progress.

Ursane triterpenoids from the bark of Terminalia arjuna

Five ursane type triterpene glucosyl esters including a new one, 2α,3β-dihydroxyurs-12,18-dien-28-oic acid 28- O-β-D-glucopyranosyl ester ( 1) were isolated from the bark of Terminalia arjuna, along with two known phenolic compounds. It is the first report of ursane type triterpenoids from this species.

Stimulation of glucose uptake by triterpenoids from Weigela subsessilis

Four ursane-type triterpenoids, corosolic acid (1), ilekudinol B (2), ursolic acid (3) and pomolic acid (4), were isolated from an EtOAc-soluble extract of the leaves of Weigela subsessilis. These bioactive compounds were evaluated for their glucose uptake activity and produced moderate to strong enhancement both in basal- and insulin-stimulated L6 muscle cells. In particular, corosolic acid exhibited the most potent activity, increasing uptake by basal- and insulin-stimulated myotubes by 2.63- and 3.33-fold, respectively; ilekudinol B produced 1.6- and 2.9-fold, ursolic acid produced 1.84- and 2.64-fold, and pomolic acid produced 1.6- and 2.8-fold increases. No cytotoxicities were observed for corosolic acid, ursolic acid and ilekudinol B in myoblasts, while pomolic acid at doses of 25 and 50 microm reduced cell viability by 19% and 21.8% upon 24 h treatment and by 48.6% and 54.1% upon 48 h treatment, respectively. These results suggest that ursane-type triterpenoids from W. subsessilis might enhance glucose uptake by acting as insulin mimics and as insulin sensitizers and that they could be useful as nontoxic diabetes treatment agents.

Cytotoxic Triterpenoids from the Stems of Microtropis japonica

Bioassay-guided fractionation of a methanol extract obtained from stems of Microtropis japonica led to the isolation of six new ursane-type triterpenoids (1-6) and a new 2,3-seco-oleanane-type triterpenoid (7), together with seven known compounds. The structures of the new compounds were elucidated using spectroscopic data analysis. Among the known compounds isolated, the main component, 8 (ursolic acid), was active for HL60 cells, and its effects on histone hyperacetylation and the inhibition of histone deacetylase (HDAC) activity were investigated.

Astilbotriterpenic Acid Induces Growth Arrest and Apoptosis in HeLa Cells through Mitochondria‐Related Pathways and Reactive Oxygen Species (ROS) Production

Astilbotriterpenic acid, a novel ursane-type triterpenoid from the rhizomes of Astilbe chinensis, has cytostatic properties in several cancer cell lines and induces apoptosis in HeLa cell. The aim of this study was to investigate the mechanisms by which such properties are exerted, with special reference to the anti-proliferative and apoptotic potential on HeLa cells. Compound 1 showed a marked concentration- and time-dependent inhibition of HeLa cell proliferation, and induced G(0)/G(1) phase arrest of HeLa cell in a dose-dependent manner. There was a quick attenuation of mitochondrial membrane potential (Deltapsi(m)) with the alterations of Bcl-2/Bax mRNA express value in 1-treated HeLa, indicating the participation of a mitochondria-related mechanism. Pretreatment of a pan-caspase inhibitor (benzyloxycarbonyl)-Val-Ala-Asp-(fluoromethyl) ketone (z-VAD-fmk) significantly increases the viability of 1-treated HeLa cells implied that the participation of caspase; Western-blot analysis showed the activation of initiator caspase-8 and caspase-9, and executor caspase-3. Meanwhile, treatment with 1 stimulates the generation of reactive oxygen species (ROS) in HeLa cell. Taken together, our data showed that compound 1 induced growth arrest and apoptosis in HeLa cells through mitochondria-related pathways and ROS production, and may be further evaluated as a chemotherapeutic agent for human cancer.

Triterpenoids from the Leaves of Diospyros kaki (Persimmon) and Their Inhibitory Effects on Protein Tyrosine Phosphatase 1B

Phytochemical study on a methanol-soluble extract of the leaves of persimmon (Diospyros kaki) resulted in the isolation of two new ursane-type triterpenoids, 3alpha,19alpha-dihydroxyurs-12,20(30)-dien-24,28-dioic acid (1) and 3alpha,19alpha-dihydroxyurs-12-en-24,28-dioic acid (2), together with 12 known ursane- and oleanane-type triterpenoids (3-14). Triterpenoids with a 3beta-hydroxy group were found to inhibit protein tyrosine phosphatase 1B (PTP1B) activity, with IC50 values ranging from 3.1+/-0.2 to 18.8+/-1.3 microM, whereas those with a 3alpha-hydroxy moiety were not active.

Chemical Components from Gentiana aristata

Two new, highly oxygenated ursane-type triterpenoids with an epidioxy function, compounds 1 and 2, as well as a new stanside-derived iridoid, compound 10, were isolated from the EtOH extract of Gentiana aristata (whole plant), together with 14 known constituents. The structures of the new compounds were established on the basis of detailed spectroscopic investigations, such as 1D- and 2D-NMR spectroscopy, as well as by means of HR-MS. Compounds 3 and 5-9 were screened in vitro for their cytotoxicities against human promyelocytic leukemia (HL-60), human ovarian (HO-8910), and human lung epithelia (A-549) cancer cells.

Organic geochemistry of the Lower Suban coal seam, South Sumatra Basin, Indonesia: Palaeoecological and thermal metamorphism implications

Hydrocarbons extracted from the Tertiary age coals from the Lower Suban seam, South Sumatra Basin, Indonesia have been investigated using gas chromatography (GC) and combined gas chromatography/mass spectrometry (GC/MS). Low rank (vitrinite–huminite reflectance ∼0.41–0.45%) coals from the Tambang Air Laya mine represent different maceral assemblages of an ideal succession of ombrogenous palaeo-peat development in a vertical section. High rank coals (vitrinite reflectance ∼1.42–5.18%) from the Suban mine have been thermally metamorphosed by an andesitic intrusion. Variations in the distributions of n-alkanes, isoprenoids and saturated and aromatic biomarkers in the low rank coals reflect variations in local source input and palaeomire conditions. Terpenoid biomarkers, such as cadinane- and eudesmane-type sesquiterpenoids and oleanane- and ursane-type triterpenoids, indicate the predominance of angiosperm plants in the palaeomire, particularly Dipterocarpaceae. The distribution of hopanoids is affected by the organic facies of the coal and their maturity, and correlates with the palaeomire evolution as derived from petrological studies. Close to the igneous intrusion, rapid thermal stress has destroyed most of the biomarkers, but variations in n-alkane distributions, attributable to palaeomire conditions, remain. Reversals in the trends for molecular parameters based on aliphatic hydrocarbons ( n-alkane distribution and pristane/phytane ratio) and aromatic hydrocarbons (methyl phenanthrenes) with coal rank are observed.

Anti-complementary Activity of Ursane-Type Triterpenoids from Weigela subsessilis

A new ursane-type triterpenoid, weigelic acid (1), and seven known compounds, ursolic acid (2), ilekudinol A (3), corosolic acid (4), ilekudinol B (5), esculentic acid (6), pomolic acid (7), and asiatic acid (8) were isolated from the leaf and stem of Weigela subsessilis. The structure of the new triterpenoid was established as 1beta,2alpha,3alpha,23-tetrahydroxyurs-12-en-28-oic acid on the basis of spectroscopic analyses. In addition, the isolated compounds were evaluated for their anti-complement activity against the classical pathway of the complement system. Of these, compounds 1-2 and 4-8 exhibited anti-complement activity with IC50 values of 152, 90, 130, 51, 56, 4, and 163 microM, respectively, whereas 3 was inactive. This shows that a carboxylic group of ursane-type triterpenoids seems to play an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

Dammarane-type triterpenes from the Brazilian medicinal plant Cordia multispicata.

From the Brazilian medicinal plant Carucaá (Cordia multispicata), oleanane- and ursane-type triterpenoids were previously reported as anti-androgenic constituents of the plant. In this study, purification of the polar elements of the EtOAc-soluble fraction of the plant revealed nine novel dammarane-type triterpenes, named cordianols A-I (1-9) along with the known compound cordialin A (10). The structures of these new compounds were elucidated by means of spectral methods including HRFABMS, (1)H NMR, (13)C NMR, and 2D NMR (HMQC, HMBC, NOESY). Absolute configuration at C-23 of compound 7 was determined by an excitone chirality method. Some of these new compounds revealed a hemiketal structure on the A ring and a hydroxylated or epoxidated 20(22)-(E)-ene side chain and showed weak anti-androgenic activity.

Structure-activity relationship of triterpenoids isolated from Mitragyna stipulosa on cytotoxicity.

Chromatographic separation of the stem bark extract of Mitragyna stipulosa afforded triterpene derivatives ursolic acid (1), quinovic acid (2), quinivic acid 3-O-beta-D-glucopyranoside (3, quinovin glycoside C), quinovic acid 3-O-[(2-O-sulfo)-beta-D-quinovopyranoside] (4, zygophyloside D) and quinovic acid 3-O-beta-D-quinovopyranosyl-27-O-beta-D-glucopyranosyl ester (5, zygophyloside B). These five compounds were subjected to the cytotoxicity on MTT assay system. Compound 1 among tested showed the most potent cytotoxicity. Quinovic acid showed less potent cytotoxicity than ursolic acid and sugar linkages to 2 decreased the cytotoxicity. Compound 4 more potent than 3 with indicate that the sulfonyl group significantly enhances the activity. This indicates that the glycosidic linkage in ursane-type triterpenoids has mainly negative effect on cytotoxicity unlike in oleanane-type glycosides.

Triterpenoid saponins from Ilex kudincha.

Ten new triterpene saponins, ilekudinosides A-J (2, 6-8, 10, 13-17), together with seven known triterpene saponins, ilexoside XLVIII (1); cynarasaponin C (5); latifolosides A (9), C (3), G (12), and H (4); and kudinoside G (11), were isolated from an aqueous extract of the leaves of Ilex kudincha. They possessed oleanane- and ursane-type triterpenoids as the aglycons. The structures were elucidated by 1D and 2D NMR experiments, including ROE difference, HOHAHA difference, 1H-1H COSY, and 1H-13C COSY (HMQC, HMBC) methods and sugar analysis. Compounds 1 and 5 exhibited acyl CoA cholesteryl acyl transferase (ACAT) inhibitory activity.

Triterpenoids and A Diterpene fromEuphorbia iberica

From the aerial parts of Euphorbia iberica, an ingenane diterpene ester, ingenol 20-eicosanoate, and three ursanetype triterpenoids, 3beta-acetoxy-urs-12-ene-1beta,11alpha-diol, 3beta-( E)-coumaroyloxy-urs-12-ene, and 3beta-( Z)-coumaroyloxy-urs-12-ene have been isolated together with known cylcoartane-type triterpenes, a flavone, and coumarins. The first four compounds are new and their structures were determined by spectroscopic methods.

Rhoiptelenyl Acetate, a New Pentacyclic Triterpenoid from Ficus thunbergii

Rhoiptelenol, (2), isolated from Ficus thunbergii Maxim. (Moraceae), has been reported as a triterpenoid component. The title compound, (1), whose molecular formula was shown by its high-resolution mass spectrum to be C32H52O2, was obtained from (2) by acetylation with Ac2O and pyridine. The structure of (1) was proved by NMR spectroscopy to be one of a rearranged ursane-type triterpenoid with five six-membered rings. We have described the conformation and geometry of (1) by an X-ray crystallographic analysis and molecular-mechanics calculations.

Triterpenoids from the Aerial Parts of Lantana camara

A new Δ 12 -oleanane triterpenoid and a new Δ 12 -ursane type triterpenoid, camarilic acid [1] and camaracinic acid [2], respectively, have been isolated from the aerial parts of Lantana camara, along with five known triterpenes, namely, oleanonic acid, ursonic acid, lantadene A, betulinic acid, and oleanolic acid. The new compounds have been characterized as 3,25-epoxy-3α-methoxy-22β-[(Z)-2'-methyl-2'-butenyloxy]-12-oleanen-28-oic acid [1] and 3,25-epoxy-3α-methoxy-22β-[(Z)-2'-methyl-2'-butenyloxy]-12-ursen-28-oic acid [2], respectively, through chemical transformation and spectroscopic studies.

Stereochemistry of hydrogen peroxide - acetic acid oxidation of ursolic acid and related compounds.

Stereochemistry of a number of oxidized derivatives of ursolic acid was established using NMR data and X-ray analysis. Full signal assignments were made in 1 H and 13 C NMR spectra of 26 natural and synthetic ursane type triterpenoids. Possible mechanisms of oxidation of ursolic acid and related compounds by peracids, as well as mechanisms of secondary processes, were formulated basing on chemical behavior and molecular mechanics calculations of the starting materials and certain intermediate species.

Tannins and related compounds. LXVII. Isolation and characterization of castanopsinins A-H, novel ellagitannins containing a triterpenoid glycoside core, from Castanopsis cuspidata var. sieboldii NAKAI. (3).

A new class of ellagitannins, castanopsinins A-H (1, 6, 25, 27, 32, 42, 47 and 51), containing a triterpenoid glycoside core, have been isolated from the leaves of Castanopsis cuspidata var. sieboldii NAKAI (Fagaceae). On the basis of spectroscopic and chemical data these compounds have been characterized as 3, 23-(R)-(1), 24-O-galloyl-3, 23-(R)-(6), 2, 3-(R)-(25), 3, 23-(S)-(27), 3, 24-(S)-(32), 24-O-galloyl-3, 23-(S)- (42), 3'-O-galloyl-23, 24-(R)- (47) and 24, 3'-di-O-galloyl-3, 23-(R)-hexahydroxydiphenoyl (51) 2α, 3β, 23, 24-tetrahydroxyolean(urs)-12-en-28-oic acid 28O-β-D-glucopyranosides. In addition, separation of structural isomers consisting of a mixture of oleanane- and ursane-type triterpenoids was successfully achieved.