A new ursane-type triterpene,cymosic acid from Rosa cymosa

A new ursane-type triterpene, cymosic acid (1) together with two known compounds, 3β,19α-dihydroxy-2-oxo-12-ursen-28-oic acid (2) and 2α,19α-dihydroxy-3-oxo-12-ursen-28-oic acid (3), were isolated from Rosa cymosa Tratt. The structure of compound 1 was elucidated by analyzing its ¹H and ¹³C NMR, ¹H–¹H COSY, HSQC, HMBC, NOESY, and HR-ESI-MS values. The three compounds were found to display moderate inhibitory activities against nitric oxide production in lipopolysaccharide-activated macrophage cell lines, RAW 264.7 cells.     

Microbial transformation of oleanolic acid by Trichothecium roseum

Microbial transformation of the oleanolic acid (1) using Trichothecium roseum (pers.) Link (M 95.56) has resulted in the isolation of two new hydroxylated type metabolites, characterized as 15α-hydroxy-3-oxo-olean-12-en-28-oic acid (2) and 7β,15α-dihydroxy-3-oxo-olean-12-en-28-oic acid (3). The structure elucidation of these metabolites was based primarily on HR-EIMS, 1D NMR, and 2D NMR analyses.     

Microbial transformation of asiatic acid by Alternaria longipes

Asiatic acid is a major pentacyclic triterpene isolated from Centella asiatica. It shows a variety of bioactivities. In order to obtain its derivatives, potentially useful for detailed pharmacological studies, the substrate was subjected to incubations with selected micro-organisms. In this work, asiatic acid was converted into three new compounds: 2α,3β,23,30-tetrahydroxyurs-12-ene-28-oic acid (1), 2α,3β,22β,23-tetrahydroxyurs-12-ene-28-oic acid (2), and 2α,3β,22β,23,30-pentahydroxyurs-12-ene-28-oic acid (3) by the fungus Alternaria longipes AS 3.2875. The structures of the three metabolites were determined by 1D and 2D NMR spectral data.     

Disposition of 3H-enisoprost,a gastric antisecretory prostaglandin,in healthy humans

1. After oral administration of ³H-enisoprost (450 μg) to five healthy men, as a solution in capsules, peak ³H levels of 5624 ± 566 pg equiv./ml (mean ± S.E.M.) were reached within one hour. No unchanged drug was detected in plasma.

2. Enisoprost was rapidly de-esterified to SC-36067 [(±)11α, 16ζ-dihydroxy-16-methyl-9-oxoprost-4Z, 13E-dien-1-oic acid], a pharmacologically active analogue, which reached peak concentrations of 651±200 pg/ml within 20 min of dosing. SC-36067 was eliminated metabolically, with a half-life of 1.61 h, by a combination of β-oxidation, β-oxidation and 9-keto-reduction.

3. After nine days 59.0±2.98% and 17.4±1.57% of the dose was excreted in urine and faeces respectively. The majority of this excretion was complete in two days.

4. Five urinary metabolites were identified by GC-MS. These were (±)3-[2β-(4-hydroxy-4-methyl-1E-octenyl)-3α-hydroxy-5-oxo-1α-cyclopentanyl]propanoic acid (SC-41411; 3.6% dose), (±)3-[3α,5-dihydroxy-2β-(4-hydroxy-4-methyl-1E-octenyl)-1α-cyclopentanyl]propanoic acid (SC-41411 PGF analogue; 4.8% dose), (±)3-[2β-(8-carboxy-4-hydroxy-4-methyl-1E-octenyl)-3α-hydroxy-5-oxo-1α-cyclopentanyl] propanoic acid (SC-41411-16-carboxylic acid; 22% dose), (±)3-[2β-(8-carboxy-4-hydroxy-4-methyl-1E-octenyl)-3α,5-dihydroxy-1α-cylopentanyl]propanoic acid (SC-41411 PGF analogue-16-carboxylic acid; 8.5% dose) and its γ lactone (2.6% dose).

5. These metabolites were also identified chromatographically in plasma, as were SC-36067, (±)3-[2β-(4-hydroxy-4-methyl-1E-octenyl)-5-oxo-1α-cyclopent-3-enyl]propaloic acid and (±)3-[2β-(4-hydroxy-4-methyl-1E-octenyl)-5-oxo-cyclopent-1-enyl]propanoic acid.

6. Some 5-10% of the dose was excreted in urine as tritiated water, indicating that oxidation of the 11α-hydroxy group in SC-36067 or its metabolites also occurred.     

Microbial transformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans

Microbial biotransformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans AS 3.1207 was carried out, and totally four transformed products were isolated. On the basis of the extensive spectral data, their structures were characterized as 7β-hydroxy-11-keto-boswellic acid (1), 7β,30-dihydroxy-11-keto-boswellic acid (2), 7β,16α-dihydroxy-3-acetyl-11-keto-boswellic acid (3), and 7β,15α,21β-trihydroxy-3-acetyl-11-keto-boswellic acid (4), respectively. Among them, products 1 and 2 are the new compounds.     

Feruhermonins A–C: three daucane esters from the seeds of Ferula hermonis (Apiaceae)

Seventeen daucane esters have been isolated from the seeds of Ferula hermonis Boiss (Apiaceae). Three of these sesquiterpenes, 4β-hydroxy-6α-benzoyl-7-daucen-9-one (1), 4β, 8β-dihydroxy-6α-benzoyl-dauc-9-ene (2), and 4β, 9α-dihydroxy-6α-benzoyl-dauc-7-ene (4), named feruhermonins A–C, respectively, are novel natural products. The structures of these compounds were elucidated unequivocally by a series of 1D and 2D NMR analyses. Although 4β, 8β-dihydroxy-6α-(4-hydroxy-3-methoxybenzoyl)-dauc-9-ene (3) was reported previously, the complete spectroscopic data for this compound are presented here for the first time.     

Two new triterpenoids from the fungus Perenniporia maackiae

Two new triterpenoids, 3β-(2-methoxy-oxalyloxy)-24-methylene-lanost-8-en-21-oic acid (1) and 3β-(2-methoxy-oxalyloxy)-15α-hydroxy-24-methylene-lanost-8-en-21-oic acid (2), were isolated from cultures of the fungus Perenniporia maackiae, together with two previously known triterpenoids (3 and 4). Their structures were determined by spectroscopic methods, including 1D and 2D NMR, and MS analyses. All compounds were evaluated for their cytotoxic activities on five tumor cell lines.     

Diterpenoids from the freshwater green algae Rhizoclonium hieroglyphicum with antibacterial activity

Three new isopimarane diterpenes 7β-hydroxy-19α-methylmalonyloxy-isopimara-8(14),15-diene (1), 7β-hydroxy-14-oxo-isopimara-8(9),15-dien-19oic acid (2), and 7β-hydroxy-14-oxo-19α-methylmalonyloxy-isopimara-9(11),15-diene (3) in addition to the known compounds isopimaric acid (4), 7oxo-13-epi-pimara-14,15-dien-18oic acid (5), 7oxo-13-epi-pimara-8,15-dien-18oic acid (6), and 6β-hydroxyisopimaric acid (7) were isolated from the hexane extract of Rhizoclonium hieroglyphicum. The structures of compounds 1–7 were established by 1D and 2D NMR techniques. The isolated diterpenoids were screened for antimicrobial activity against gram-positive and gram-negative bacteria and yeast strains.     

Microbial transformation of the anti-diabetic agent corosolic acid by Cunninghamella echinulata

The pentacyclic triterpenoid corosolic acid was metabolized by Cunninghamella echinulata CGMCC 3.2000 to its C-24 aldehyde group metabolite and five other hydroxylated metabolites: madasiatic acid (2), 2α, 3β, 7β-trihydroxyurs-12-en-28-oic acid (3), 2α, 3β, 15α-trihydroxyurs-12-en-28-oic acid (4), 2α, 3β, 6β, 7β-tetrahydroxyurs-12-en-28-oic acid (5), 2α, 3β, 7β, 15α-tetrahydroxyurs-12-en-28-oic acid (6), and 2α, 3β,7β-trihydroxy-24-al-urs-12-en-28-oic acid (7); compounds 3, 5, and 7 were new compounds. The α-glucosidase inhibitory effects of the metabolites were also evaluated.     

Triterpenes from Astilbe chinensis

Six new triterpenes, 3β,6β-dihydroxyurs-12-en-27-oic acid (1), 3β,6β,24-trihydroxyurs-12-en-27-oic acid (2), 3β,6β,7α-trihydroxyurs-12-en-27-oic acid (3), 3β-acetoxy-6β-hydroxyurs-12-en-27-oic acid (4), 3β,6β,24-trihydroxyolean-12-en-27-oic acid (5), and 3β,6β,7α-trihydroxyolean-12-en-27-oic acid (6), were isolated from the rhizomes of Astilbe chinensis. Their structures were elucidated on the basis of 1D- and 2D-NMR analyses and HR-MS experiments. The isolated compounds exhibited significant cytotoxic activities against the SK-N-SH and HL-60 cell lines.     

A new <Emphasis Type="Italic">ent</Emphasis>-kaurane type diterpenoid glycoside from <Emphasis Type="Italic">Inula japonica</Emphasis> Thunb.

A new ent-kaurane type diterpenoid glycoside, 17-O-β-D-glucopyranosyl-16α-ent-kauran-19-oic acid (1), together with 17-hydroxy-16α-ent-kauran-19-oic acid (2), 16α,17-dihydroxyl-ent-kauran-19-oic acid (3), and 16α-hydroxy-17-acetoxy-ent-kauran-19-oic acid (4) were isolated from the aerial parts of Inula japonica Thunb. The structure of 1 was determined mainly by use of 1D and 2D NMR spectroscopic techniques including HSQC, ¹H-¹H COSY, HMBC, and NOESY. In addition, 4 exhibited significant inhibitory activity on NO production in LPS-stimulated RAW264.7 cells with IC₅₀ value of 14.3 μg/mL.     

New compounds with antimicrobial activities from Elaeodendron buchananii stem bark

The plant species Elaeodendron buchananii Loes is widely used in folklore medicine to manage microbial infections in Kenya. Previous studies on the plant fruits and root bark revealed the presence of steroids and terpenoids. The present phytochemical analysis of the plant stem bark has led to the isolation of four new triterpenes characterized as methyl 3β-acetoxy-11α, 19α, 28-trihydroxyurs-12-en-23-oic acid (1), 3β, 11α, 19α-trihydroxyurs-12-en-23, 28-dioic acid (2), 3β-acetoxy-19α, 23, 28-trihydroxyurs-12-ene (3) and 3-oxo-19α, 28-dihydroxyurs-12-en-24-oic acid (4), together with ten known ones (5–14), whose structures were elucidated using spectroscopic techniques. The isolate canophyllol (8) showed promising antibacterial activity against N. meningitides with MIC value of 31.25 μg/ml.     

Two new triterpenoids from Callicarpa kwangtungensis

Two new triterpenoids, 2α,3β,16α,19α,23-pentahydroxyolean-12-en-28-oic acid (1) and 2α,3α,11α,21α,23-pentahydroxyurs-12-en-28-oic acid (2), were isolated from the aerial parts of Callicarpa kwangtungensis. Their structures were elucidated by 1D and 2D analyses, as well as MS and IR spectra.     

Two new sesquiterpene polyol esters from the root barks of Celastrus angulatus

Angulatin F (1) and angulatin I (2), two new sesquiterpene polyol esters, were isolated from the root barks of Celastrus angulatus, together with six known compounds 1β,2β-diacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-15-(α-methyl) butanoyloxy-β-dihydroagrofuran (3), angulatin A (4), angulatin B (5), celangulatin E (6), 1β,2β,15-triacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-β-dihydroagrofuran (7), and celangulin I (8). The structures of 1 and 2 were elucidated as 1β,2β,6α,15-tetraacetoxy-4α-hydroxy-8β,9α-difuroyloxy-β-dihydroagrofuran and 1β,2β,6α,8β,15-pentaacetoxy-4α-hydroxy-9β-furoyloxy-β-dihydroagrofuran by spectroscopic means.     

New inhibitors of α-glucosidase in Salacia hainanensis Chun et How

The methanol extract from roots of Salacia hainanensis Chun et How afforded three new compounds, 24,26-dihydroxy-25-methoxy-tirucall-9-en-3-one (1), 2β,3β,22α-trihydroxy-lup-20(29)-ene (2) and 3β-hydroxy-2-carbonyl-lupan-29-oic acid (3), along with six known triterpenoids (4–9). Their structures were established on the basis of spectral analysis, in particular according to the data obtained by two-dimensional-NMR and high-resolution mass spectra experiments. Some of them showed much stronger inhibitory activity towards α-glucosidase than the positive control (acarbose, IC₅₀ 10.2 μM).     

Triterpenoids from the aerial parts of Lantana camara

Two new pentacyclic triterpenoids lancamarinic acid and lancamarinin have been obtained from the aerial parts of Lantana camara Linn. They were characterized as 22β-acetoxy-3,25-epoxy-3α-hydroxyolean-12-en-28-oic acid and methyl 3,25-epoxy-3α-hydroxy-11-oxo-22β-senecioyloxyolean-12-en-28-oate, respectively, through chemical transformation and exhaustive spectroscopic studies.     

Novel furostanol saponins from the bulbs of Allium macrostemon B. and their bioactivity on [Ca2+]i increase induced by KCl

Chemical reinvestigation of the ethanol extract of the dried bulbs of Allium macrostemon B. led to the isolation of two novel furostanol saponins, named macrostemonoside M (1) and macrostemonoside N (2), together with six known saponins. The structures of new compounds were elucidated on the basis of extensive spectroscopic analysis including 1D and 2D NMR as (25R)-22-hydroxy-5β-furostane-1β,2β,3β,6α-tetraol-26-O-β-d -glucopyranoside and 22-hydroxy-5β-furost-25-(27)-ene-1β,2β,3β,6α-tetraol-26-O-β-d -glucopyranoside, respectively. The pharmacological activities of all the saponins on [Ca²⁺]_i increase induced by KCl were evaluated.     

Two new casbane diterpenoids from the roots of Euphorbia pekinensis

From the roots of Euphorbia pekinensis, two new casbane diterpenoids, named pekinenins A (1) and B (2), were isolated. Their structures were elucidated as 18-hydroxy-1βH,2αH-casba-3E,7E,11E-trien-5-one (1), 5α-methoxy-1βH,2αH-casba-3Z,7E,11E-trien-18-oic acid (2) by a combination of 1D and 2D NMR spectroscopy and mass spectrometry. In the cytotoxicity assay of the two new compounds against Hela, MCF-7, and C6 human cancer cell lines, compound 1 showed moderate cytotoxic activity against two human cancer cell lines, Hela and C6, with IC₅₀ values of 42.97 and 50.00 μM, respectively.     

Two new triterpenoid saponins from Ilex cornuta

Two new triterpenoid saponins (1 and 2) were isolated from the stems of Ilex cornuta, along with two known triterpenoids (3 and 4). The structures of compounds 1 and 2 were determined as ursane-12,19-diene-28-oic acid 3β-O-β-d-glucuronopyranoside-6-O-methyl ester (1), 3α,23α-dihydroxy-olean-9(11),12-diene-28-oic acid 28-O-β-d-glucopyranosyl ester (2), on the basis of hydrolysis and spectral evidence, including 1D and 2D NMR and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) analyses. Protective effects of compounds 1–4 were tested against H₂O₂-induced H9c2 cardiomyocyte injury, and the data showed that all these compounds had no cell-protective effect.     

Odorasides A and B,new sphingolipid glucosides from Klienia odora

Two new sphingolipid glucosides, odoraside A (1) and odoraside B (2), have been isolated from chloroform-soluble fraction of the total methanolic extract of Klienia odora, together with five known compounds, β-sitosterol (3), oleanolic acid (4), betulone (5), 2,3-dihydroxy-12-oleanen-28-oic acid (6), and β-sitosterol 3-O-β-d-glucopyranoside (7). Their structures were assigned from ¹H and ¹³C NMR spectra, DEPT and by 2D COSY, NOESY, HMQC, and HMBC experiments.