Triterpenoids from enkianthus campanulatus

From the leaves of Enkianthus campanulatus were isolated three new triterpenes, 3-oxo-19,23,24-trihydroxyurs-12-en-28-oic acid, 3β,6β, 19,23-tetrahydroxyurs-12-en-28-oic acid and 3β,6β,23-trihydroxyurs-12-en-28-oic acid.     

Triterpenoid saponins from the aerial parts of Trifolium argutum Sol. and their phytotoxic evaluation

Four triterpenoid saponins (1–4) were isolated from the aerial parts of Trifolium argutum Sol. (sharp-tooth clover) and their structures were elucidated by comprehensive spectroscopic analysis, including 1D and 2D NMR techniques, mass spectrometry and chemical methods. Two of them are new compounds, characterized as 3-O-[α-l-rhamnopyranosyl-(1→2)-β-d-galactopyranosyl-(1→2)-β-d-glucuronopyranosyl]-3β,24-dihydroxyolean-12-ene-22-oxo-29-oic acid (1) and 3-O-[β-d-galactopyranosyl-(1→2)-β-d-glucuronopyranosyl]-3β,24-dihydroxyolean-12-ene-22-oxo-29-oic acid (2). The occurrence of 3β,24-dihydroxyolean-12-ene-22-oxo-29-oic acid (melilotigenin) in its natural form is reported for the first time as a triterpenoid aglycone within Trifolium species. The phytotoxicity of compounds was evaluated on four STS at concentration 1 μM to 333 μM. Compound 1 was the most active, showing more than 60% inhibition on the root growth of L. sativa at the higher dose, with IC₅₀ (254.1 μM) lower than that of Logran^® (492.6 μM), a commercial herbicide used as positive control. The structure–activity relationships indicated that both aglycones and glycosidic parts may influence the phytotoxicity of saponins.     

A new ursane-type triterpenoid glycoside from Centella asiatica leaves modulates the production of nitric oxide and secretion of TNF-α in activated RAW 264.7 cells

One new ursane-type triterpenoid glycoside, asiaticoside G (1), five triterpenoids, asiaticoside (2), asiaticoside F (3), asiatic acid (4), quadranoside IV (5), and 2α,3β,6β-trihydroxyolean-12-en-28-oic acid 28-O-[α-l-rhamnopyranosyl-(1→4)-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl] ester (6), and four flavonoids, kaempferol (7), quercetin (8), astragalin (9), and isoquercetin (10) were isolated from the leaves of Centella asiatica. Their chemical structures were elucidated by mass, 1D- and 2D-nuclear magnetic resonance (NMR) spectroscopy. The structure of new compound 1 was determined to be 2α,3β,23,30-tetrahydroxyurs-12-en-28-oic acid 28-O-[α-l-rhamnopyranosyl-(1→4)-β-d-glucopyranosyl-(1→6)-β-d-glucopyranosyl] ester. The anti-inflammatory activities of the isolated compounds were investigated on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Asiaticoside G (1) potently inhibited the production of nitric oxide and tumor necrosis factor-α with inhibition rates of 77.3% and 69.0%, respectively, at the concentration of 100 μM.     

肋果茶中的萜类化学成分研究

从肋果茶(Sladenia celastrifolia)95％乙醇提取物的乙酸乙酯部位中分离得到15个萜类化合物,经波谱学方法分别鉴定为sladeniafolin A(1),grasshopper ketone (2),(3S,5R,6S,7E,9R) -7-megastigmene-3,6,9-triol (3),hedytriol (4),(3S,5R,6R,7E,9R) -3,5,6,9-tetrahydroxy-7-megastigmene(5),1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′-trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien -2-one (6),2α,3α,19α,23-tetrahydroxyurs-12-en-28-oic acid (7),2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid(8),pomolic acid(9),3-O-acetyl pomolic acid(10),ursaldehyde (11),camarolide (12),3β-hydroxyurs-11-en-13β(28) -olide (13),3β-hydroxy -11α,12α-epoxy-urs-13β,28-olide (14)和28-0-β-D-glucopyranosyl euscaphic acid (15).以上化合物均首次从该植物中分离得到,其中1为新的C9裂环烯醚萜.     

New derivatives of ursolic acid through the biotransformation by Bacillus megaterium CGMCC 1.1741 as inhibitors on nitric oxide production

Microbial transformation of ursolic acid (1) by Bacillus megaterium CGMCC 1.1741 was investigated and yielded five metabolites identified as 3-oxo-urs-12-en-28-oic acid (2); 1β,11α-dihydroxy-3-oxo-urs-12-en-28-oic acid (3); 1β-hydroxy-3-oxo-urs-12-en-28, 13-lactoe (4); 1β,3β, 11α-trihydroxyurs-12-en-28-oic acid (5) and 1β,11α-dihydroxy-3-oxo-urs-12-en-28-O-β-d-glucopyranoside (6). Metabolites 3, 4, 5 and 6 were new natural products. Their nitric oxide (NO) production inhibitory activity was assessed in lipopolysaccharide (LPS) – stimulated RAW 264.7 cells. Compounds 3 and 4 exhibited significant activities with the IC₅₀ values of 1.243 and 1.711 μM, respectively. A primary structure-activity relationship was also discussed.     

锐尖山香圆叶中三萜类成分的研究

从锐尖山香圆(Turpinia arguta (Lindl.) Seem.)叶中分离得到了11个三萜类化合物。通过光谱分析,分别鉴定其结构为熊果酸(1), 3β,6β,23-trihydroxy-12-oleanen-28-oic acid (2), 3β,6β,23-trihydroxyurs-12-en-28-oic acid (3), 3β,6β,19α,23-tetrahydroxyurs-12-en-28-oic acid (4), 1 α, 3β,23-trihydroxy-12-oleanen-28-oic acid (5), arjunglucoside II (6), rosamultin (7), 3β-O-β-D-glucopyranoylcincholic acid (8), cinchonaglycoside C (9), mussaendoside S (10) 和3β-O-β-D-glucopyranosyl quinovic acid 28-O-β-D-glucopyranosyl ester (11)。除化合物1和6,其它化合物均为首次从山香圆叶中分离得到。     

Three new 18,19-seco-ursane glycosides from Elsholtzia bodinieri

Chromatographic separation of an extract of the aerial part of Elsholtzia bodinieri resulted in the isolation of three new 18,19-seco-ursane glycosides, bodiniosides E-G (1–3). Their structures were elucidated as 2α,12β,23-trihydroxy-3-(β-d-glucopyranosyl)-19-oxo-18,19-seco-urs-13(18)-en-28-O-β-d-glucopyranosyl ester (1), 3-β-d-glucopyranosyl-19-β-d-glucopyranosyl-12β,21-dihydroxy-18,19-seco-urs-13(18)-en-28-oic acid (2), and 2α,12β,21-trihydroxy-3-β-d-glucopyranosyl-19-β-d-glucopyranosyl-18,19-seco-urs-13(18)-en-28-oic acid (3), respectively, by extensive NMR techniques, including 1D- and 2D-NMR experiments, as well as comparing with spectral data with those of the known analogues.     

Triterpenoid profile and bioactivity study of Oenothera maritima

Four new triterpenoids, 2α,3α,20β,23-tetrahydroxy-ursa-12,19(29)-dien-28-oic acid (1), 2α,3α,20β,23-tetrahydroxy-ursa-12,19(29)-dien-28,20β-lactone (2), 2α,3α-dihydroxy-ursa-12,19-dien-28-oic acid 28-O-β-d-glucopyranoside (3) and 2α,3α,23-trihydroxy-ursa-12,19(29)-dien-28-oic acid (4) together with six known compounds (5–10), were isolated from the aerial parts of Oenothera maritima Nutt. Their structures were elucidated on the basis of spectroscopic data and chemical methods. Compounds 1, 3–10 were evaluated for their in vitro thrombin inhibitory activity and their selectivity against factor Xa and trypsin.     

New 19α-hydroxyursane-type triterpenes from the leaves of Meyna spinosa (= Vangueria spinosa), Rubiaceae

Two new 19α-hydroxyursane-type triterpenes, 2α,3α,19α,24,28-pentahydroxyurs-12-ene (1) and meyanthic acid, 3β-acetoxy-2β,19α,23-trihydroxyurs-12-en-28-oic acid (2) along with one new aliphatic ester, myricyl pentadecanoate (3) and five known compounds, 19α-hydroxyasiatic acid (4), oleanolic acid (5), myricyl alcohol (6), β-sitosterol (7) and its glycoside (8) were isolated from the methanolic leaf extract of Meyna spinosa Roxb. ex Link (= Vangueria spinosa Roxb., Rubiaceae). The structures of the new compounds were elucidated on the basis of extensive spectroscopic (including 2D NMR) analysis and comparison with literature. Except oleanolic acid, isolation of known compounds was reported for the first time from this plant.     

Seven new triterpenoids from the aerial parts of Ilex cornuta and protective effects against H2O2-induced myocardial cell injury

Seven new triterpenoids (1–7), together with two known ones (8–9), were isolated from the aerial parts ofIlex cornuta. The leaves of I. cornuta are the major source of “Kudingcha”, a popular herbal tea consumed in China and other countries. The structures of compounds 1–7 were determined as 20-epi-urs-12,18-dien-28-oic acid 3β-O-α-l-arabinopyranoside (1), 20-epi-urs-12,18-dien-28-oic acid 2′-O-acetyl-3β-O-α-l-arabinopyranoside (2), 20-epi-urs-12,18-dien-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (3), 3β,23-dihydroxy-20-epi-urs-12,18-dien-28-oic acid (4), 23-hydroxy-20-epi-urs-12,18-dien-28-oic acid 3β-O-α-l-arabinopyranoside (5), 23-hydroxy-20-epi-urs-12,18-dien-28-oic acid 3β-O-β-d-glucuronic acid (6), 23-hydroxy-20-epi-urs-12,18-dien-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (7), on the basis of spectroscopic analyses (IR, ESI–MS, HR-ESI–MS, 1D and 2D NMR) and chemical reactions. Protective effects against H₂O₂-induced H9c2 cardiomyocyte injury were tested in vitro for compounds 1–9, and the data showed that compound 4 had significant cell-protective effect. Compounds 1-9 did not show significant DPPH radical scavenging activity.     

Studies on the Structures of Two New Triterpene Saponins C and D from Polygala japoni-ca Houtt

Two new triterpene saponins C and D have been isolated from the aerial parts of Polygala japonica Houtt. Their molecular formulas: C42H68O15 were structural isomers of each other. Acid hydrolysis of the two saponins all produced a sapogenin (2a, 3a, 24-trihydroxyo-lean-12-ene-28-oic acid) and D-glucoses. But only the saponin D could be hydrolyzed in the alkaline solution, the products were identical with those from acid hydrolysis. Their structures have been established by means of 1HNMR,13CNMR and MS as 3-O-[β-D-glucopyranosyl(l→2)β-D-glucopyranosyl] 2α, 3α, 24-trihydroxyolean-12-ene-28-oic acid, 28-O-[β-D-glucopy-ranosyl (1→2)-β-D-glucopyranosyl] 2α, 3α, 24-trihydroxyolean-12-ene-28-oic acid.     

Study on the Structure of a New Triterpene Saponin B from Polygala japoniea Houtt

A new triterpene saponin B has been isolated from the earial parts of Polygala japonica Houtt in folk-lore medicine. Its molecular: C48H78O20, m.p. 199–202℃, [α]D23+30.0 (C, 0.5, CH3OH). Acidic hydrolysis of this saponin gave a sapogenin (2α, 3α, 24-tri-hydroxyolean-12-ene-28-oic acid) and D-glucose. The structure of saponin B was elucidated as 28-O- [β-D-glucopyranosyl (1→2) -β-D-glucopyranosyl (1→2) -β-D-glucopy- ranosyl] 2α, 3α, 24-trihydroxyolean-12-ene-28-oic acid mainly by 13C-NMR, MS and some chemical transfomations.     

尼泊尔水东哥的化学成分研究

从尼泊尔水东哥树皮的95%乙醇提取物中首次分离到12个化合物,应用波谱方法或与已知品对照的手段鉴定为auranamide(1)、aurantiamide benzoate(2)、齐墩果酸(3)、β-谷甾醇(4)、β-胡萝卜甙(5)、乌苏酸(6)、2α,3α-二羟基-12-烯-28-乌苏酸(7)、2α,3β,24-三羟基-12-烯-28-乌苏酸(8)、(2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol(9)、2α,3α,24-三羟基-12-烯-28-齐墩果酸(10)、2α,3β-二羟基-12-烯-28-乌苏酸(11)和2α,3α,24-三羟基-12-烯-28-乌苏酸(12)。     

Caulophyllogenin: A novel triterpenoid from roots of Caulophyllum robustum

A new triterpenoid acid was isolated from Caulophyllum robustum roots. Its structure was proved to be 3β, 16α, 23-tri-hydroxy-olean-12-ene-28-oic acid.     

Triterpenoidal saponins of Pulsatilla koreana roots

Sixteen (1-16) triterpenoidal saponins were isolated from the roots of Pulsatilla koreana, of which four were determined as the previously unknown 23-hydroxy-3β-[(O-α-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid 28-O-β-D-glucopyranosyl ester (1), 23-hydroxy-3β-[(O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid 28-O-β-D-glucopyranosyl ester (2), 3β-[(O-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl ester (3), and 3β-[(O-α-L-rhamnopyranosyl-(1 → 2)-O-[β-D-glucopyranosyl-(1 → 4)]-α-L-arabinopyranosyl)oxy]lup-20(29)-en-28-oic acid 28-O-α-L-rhamnopyranosyl-(1 → 4)-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl ester (4), respectively, based on spectroscopic analysis. The inhibition of the lipopolysaccharide-induced nitric oxide production of sixteen isolated compounds was evaluated in RAW 264.7 cells at concentrations ranging from 1 μM to 100 μM.     

Terpenes of Dipterocarpus and Doona species

From the resins of Dipterocarpus hispidus, Dipterocarpus zeylanicus and Doona macrophylla, asiatic (2α,3β,23α-trihydroxyurs-12-en-28-oic) and 2α,3β-dihydroxyurs-12-en-28-oic acids have been isolated. The resin of Doona macrophylla contains ursolic acid and that of Doona congestiflora asiatic acid, 20β-hydroxy-3-oxo dammar-23-ene (Dipterocarpol) and a dihydroxyolean-12-en-28-oic acid. The bark of Dipterocarpus hispidus contains betulinic acid, dipterocarpol, and 3β,20β-dihydroxydammar-23-ene (dammarenediol 20S) whilst the timber contained dipterocarpol and asiatic acid.     

Triterpenoids from Mallotus repandus: Three new δ-lactones

The leaves of Mallotus repandus contain friedelin, 3β-hydroxy-13α-ursan-28,12β-olide (1), its benzoate (2) and ursolic acid. The stems contain friedelin, lupeol, α-amyrin, 2 and 3α-hydroxy-13α-ursan-28, 12β-olide (3), 21α-hop-22(29)-ene-3β,30-diol and ursolic acid. 1–3 are new compounds.     

Bioactivity-guided isolation of cytotoxic triterpenoids from the trunk of Berberis koreana

A bioassay-guided fractionation and chemical investigation of the trunk of Berberis koreana resulted in the isolation and characterization of two new triterpenoids, 23-trans-p-coumaroyloxy-2α,3α-dihydroxyolean-12-en-28-oic acid (1), and 23-cis-p-coumaroyloxy-2α,3α-dihydroxyolean-12-en-28-oic acid (2), along with seven known triterpenoids (3–9). The structures of the new compounds were determined on the basis of spectroscopic analyses including 2D NMR. The cytotoxic activities of the triterpenes (1–9) were evaluated by determining their inhibitory effects on human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15) using the SRB assay. Compounds 5 and 6 showed potent cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 cell lines (IC₅₀ (5): 4.37, 7.04, 9.72, and 5.83 μM, and IC₅₀ (6): 5.57, 7.84, 13.29, and 5.61 μM, respectively).     

A new triterpene lactone from Gymnocladus dioica

2β,23-Dihydroxyacacic acid lactone was isolated from Gymnocladus dioica as an artifact from 2β, 3β 16β, 21β, 23-pentahydroxyolean-12-ene-28-oic acid.     

Triterpenes from the roots of Lantana montevidensis with antiprotozoal activity

Bioassay guided fractionation of the roots of Lantana montevidensis (Verbenaceae) has resulted in the isolation and identification of three new triterpenoids; 13β-hydroxy-3-oxo-olean-11-en-28-oic acid (1), 12β,13β-dihydroxyolean-3-oxo-28-oic acid (2) and 12β,13β,22β-trihydroxyolean-3-oxo-28-oic acid (3) in addition to nine known compounds: oleanonic acid (4), oleanolic acid (5), 3β,25β-dihydroxy-olean-12-en-28-oic acid (6), lantadene A (7), 19α-hydroxy-3-oxo-olean-12-en-28-oic acid (8) pomolic acid (9), camaric acid (10) together with β-sitosterol (11) and β-sitosterol-3-O-β-d-glucoside (12). The structures of the isolated metabolites were elucidated based on comprehensive 1D and 2D NMR spectroscopic data as well as HR-ESI–MS. The extracts and the isolated metabolites were evaluated for their antiprotozoal and antimicrobial activities. Compound 2 showed antibacterial activity against Staphylococcus aureus and methicillin resistant S. aureus with IC₅₀ values against both organisms of 2.1 μM and compound 10 showed activity against same organisms with IC₅₀ values 8.74 and 8.09 μM, respectively, compared to the positive control ciprofloxacin (IC₅₀ = 0.3 μM against S. aureus and MRSA). Compounds 1, 4, 5, 6, and 10 showed moderate antileishmanial activity with IC₅₀ values ranging between (2.54–14.95 μM) and IC₉₀ values ranging between (11.90–19.47 μM), using pentamidine as a control (IC₅₀ values 2.09 ≥ 16.8 μM) and IC₉₀ values ranging between (4.72 ≥ 16.8 μM). These compounds also showed highly potent antitrypanosomal activity with IC₅₀ values ranging between (0.39–7.12 μM) and IC₉₀ values ranging between (1.91–10.51 μM), which are more efficient than the DFMO, the antitrypanosomal drug employed as positive control (IC₅₀ and IC₉₀values 11.82 and 30.82 μM).