Six unprecedented 2-(2-phenethyl)chromone dimers from agarwood of Aquilaria filaria.

Six new dimeric 2-(2-phenylethyl)chromones (1-6) were successfully isolated from the ethanol extract of agarwood of Aquilaria filaria from Philippines under HPLC-MS guidance. Compounds 1-6 are all dimers formed by linking 5,6,7,8-tetrahydro-2-(2-phenylethyl)chromone and flindersia 2-(2-phenylethyl)chromone via a single ether bond, and the linkage site (C5-O-C8'') of compound 2 is extremely rare. A variety of spectroscopic methods were used to ascertain their structures, including extensive 1D and 2D NMR spectroscopic analysis, HRESIMS, and comparison with literature. The in vitro tyrosinase inhibitory and anti-inflammatory activities of each isolate were assessed. Among these compounds, compound 2 had a tyrosinase inhibition effect with an IC50 value of 27.71 ± 2.60 µM, and compound 4 exhibited moderate inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with an IC50 value of 35.40 ± 1.04 µM.

Two New AChE Inhibitors Isolated from Li Folk Herb Heilaohu "Kadsura coccinea" Stems.

Two new triterpenoids, named kadsuricoccins A and B, together with three known ones, were isolated from the Li folk herb Heilaohu, the stems of Kadsura coccinea (Lem.) A. C. Smith, which was used for food and as a healthy supplement. Their structures were elucidated by comprehensive analyses of mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopic data. To search healthy components, an acetylcholinesterase (AChE) inhibitory activity test by Ellman's Method was conducted, kadsuricoccins A and B showed activity with the AChE inhibit index (AII) up to 68.96% ± 0.19% and 57.8% ± 0.11% at 94 nM (compared with positive control tacrine AII 79.80% ± 0.20%, 9.4 nM), respectively.

A phytochemical investigation of Stemona parviflora roots reveals several compounds with nematocidal activity.

Twelve undescribed compounds including six phenanthrene derivatives (parviphenanthrines A-F), two stilbene derivatives (parvistilbines A-B), three esters (parviesters A-C), and one sesquiterpenoid (parvidiol A) were isolated from the roots of Stemona parviflora, together with twenty-two known ones. The structures of the undescribed compounds were elucidated based on the analyses of their spectroscopic data. The absolute configuration of parviphenanthrine A was determined by the quantum ECD calculations. Parviphenanthrines A and E, stemanthrene A, stilbostenin E, 4-hydroxy-benzenepropanol-α-benzoate, and (E)-4-hydroxycinnamic acid methyl ester showed nematocidal activity against Meloidogyne incognita with IC50 values of 14.02 ±â€¯0.32, 2.51 ±â€¯0.13, 17.10 ±â€¯0.65, 2.05 ±â€¯0.07, 4.22 ±â€¯0.31, and 1.07 ±â€¯0.05 µM, respectively.

Tomenphantadenine, an unprecedented germacranolide-adenine hybrid heterodimer from the medicinal plant Elephantopus tomentosus L.

An unusual adenine-substituted germacrane sesquiterpene lactone, tomenphantadenine (1), has been isolated from the whole plant of Elephantopus tomentosus L. The structure of this compound was established by comprehensive spectroscopic analysis including high resolution (HR) ESI-MS, 1D and 2D nuclear magnetic resonance (NMR) spectroscopic data. This compound features novel hybrid pattern of germacrane sesquiterpene with adenine through C-N linkage, and a possible biosynthetic pathway for it was proposed. Compound 1 showed potent antibacterial activity against the gram-positive Staphylococcus aureus and weak acetylcholinesterase (AChE) inhibitory activity.

Daphnauranins A and B, two new antifeedants Isolated from Daphne aurantiaca roots.

Daphnauranins A (1) and B (2), two sesquiterpenoids were isolated from the roots of Daphne aurantiaca Diels. One is an unprecedented 5/7 oxacycloheptane ring system, the other is a sesquiterpene-lignan complex. Their structures were elucidated by comprehensive spectroscopic methods including MS and NMR. Their absolute configurations were further confirmed by the quantum ECD calculations. Daphnauranins A and B showed anti-insect activities against male fruit fly with anti-feeding rate up to 46.2±7.1 and 44.7±5.4% at 1mM, respectively.

Nematicidal Stemona Alkaloids from Stemona parviflora.

Eight new alkaloids, 3ß-n-butylstemonamine (1), 8-oxo-3ß-n-butylstemonamine (2), 3-n-butylneostemonine (3), 10-epi-3-n-butylneostemonine (4), 8-oxo-oxymaistemonine (5) protostemonine N4-oxide (6), (19S)-hydroxy-21-methoxystemofoline (7), and parvistemonine A (8), were isolated from the roots of Stemona parviflora, together with 17 known alkaloids. The structures of the new alkaloids were elucidated based on a comprehensive spectroscopic data analysis. The absolute configurations of 1-4 were determined by the ECD exciton chirality method and quantum ECD calculations. Protostemonine (10) and stemofoline (12) showed strong nematicidal activity against Panagrellus redivevus, with IC50 values of 0.10 and 0.46 µM, respectively.

Three new sesquiterpenoids from agarwood of Aquilaria crassna.

Three new sesquiterpenoids (1-3), together with two known ones were isolated from the EtOAc extract of agarwood originating from Aquilaria crassna. The new compounds were elucidated on the basis of spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). Compounds 1-5 were isolated from agarwood of A. crassna for the first time. In the acetylcholinesterase inhibition experiment of 2-5, compound 3 showed acetylcholinesterase inhibition activity (IR 42.9±0.6%). Compound 5 expressed antibacterial activities against Staphylococcus aureus and Ralstonia solanacearum with diameter of the inhibition zones of 12.35±0.11mm and 16.90±0.09mm, respectively.

Two new guaiane sesquiterpenoids from Daphne holosericea (Diels) Hamaya.

Two new sesquiterpenoids with guaiane skeletons-holosericin A (1) and holosericin B (2)-were isolated from the medicinal plant Daphne holosericea (Diels) Hamawa (Thymelaeceae). Their structures were elucidated by 1D and 2D-NMR spectroscopy, as well as HR-ESI-MS data. Compounds 1 and 2 were evaluated for inhibitory activities against acetylcholinesterase and compound 2 showed a moderate activity with 31% inhibition.

Chemical constituents from the stems of Excoecaria acertiflia.

Six new compounds, including two diterpenoids excocarinols F and G (1 and 2, resp.), two carotane (daucane) sesquiterpenoids excoecafolinols A and B (3 and 4, resp.), one lignanoid compound, excoecanol A (5), and one simple phenol, excoecanol B (6), together with 17 known compounds, were isolated from the BuOH extract of Excoecaria acerifolia Didr. stems. Their structures were elucidated through the analysis of the spectroscopic data. The AChE-inhibitory activities of 17 compounds were evaluated and revealed that four of them possessed moderate inhibitory activities against AChE.

Terpenoids and their anti-feedant activity from Cipadessa cinerascens.

Eight tetranortriterpenoids (1-8) and two sesquiterpenoids (9 and 10) including two new compounds, cineracipadesin G (1) and 1ß-hydroperoxy-6α-hydroxy-eudesm-4(15)-ene (9), were isolated from the EtOAc extract of branches of Cipadessa cinerascens. The structures of two new compounds were elucidated by 1D and 2D NMR and MS spectroscopic analyses. The anti-feedant activity of two tetranortriterpenoids (1 and 7) was tested and obvious anti-feedant effects were detected.

[Chemical constituents from Ganoderma philippii].

The chemical investigation on Ganoderma philippii led to the isolation of sixteen compounds by silica gel and Sephadex LH-20 column chromatography. On the basis of spectroscopic data analyses, their structures were elucidated as 2, 5-dihydroxyacetophenone (1), methyl gentisate (2), (S) -dimethyl malate (3), muurola-4, 10 (14) -dien-11beta-ol (4), dihydroepicubenol (5), 5-hydroxymethylfuran carboxaldehyde (6), ergosta-7, 22E-dien-3beta-ol (7), ergosta-7, 22E-dien-3-one (8), ergosta-7, 22E-diene-2beta, 3alpha, 9alpha-triol (9), 6/beta-methoxyergo-sta-7, 22E-dien-3beta, 5alpha-diol (10), ergosta-4, 6, 8(14), 22E-tetraen-3-one (11), ergosta4, 6, 8-(14), 22E-etetraen-3beta-ol (12), 5alpha, 8alpha-epidioxy-ergosta-6, 22E-dien-3beta-ol (13), 7alpha-methoxy-5alpha, 6alpha-epoxyergosta-8-(14), 22E-dien-3beta-ol (14), ergosta-8, 22E-diene-3beta, 5alpha, 6beta, 7alpha-tetraol (15), and ergosta-5, 23-dien-3beta-ol, acetate (16). All the compounds were obtained from this fungus for the first time, and compounds 4 and 5 were isolated from the Ganoderma genus for the first time.

Wikstroelide M potently inhibits HIV replication by targeting reverse transcriptase and integrase nuclear translocation.

AIM: To evaluate the anti-HIV activity and mechanism of action of wikstroelide M, a daphnane diterpene from Daphne acutiloba Rehder (Thymelaeaceae). METHODS: The anti-HIV activities of wikstroelide M against different HIV strains were evaluated by cytopathic effect assay and p24 quantification assay with ELISA. The inhibitory effect of wikstroelide M on HIV reverse transcription was analyzed by real-time PCR and ELISA. The effect of wikstroelide M on HIV-1 integrase nuclear translocation was observed with a cell-based imaging assay. The effect of wikstroelide M on LEDGF/p75-IN interaction was assayed by molecular docking. RESULTS: Wikstroelide M potently inhibited different HIV-1 strains, including HIV-1IIIB, HIV-1A17, and HIV-19495, induced a cytopathic effect, with EC50 values ranging from 3.81 to 15.65 ng·mL⁻¹. Wikstroelide M also had high inhibitory activities against HIV-2ROD and HIV-2CBL-20-induced cytopathic effects with EC50 values of 18.88 and 31.90 ng·mL⁻¹. The inhibitory activities of wikstroelide M on the three HIV-1 strains were further confirmed by p24 quantification assay, with EC50 values ranging from 15.16 to 35.57 ng·mL⁻¹. Wikstroelide M also potently inhibited HIV-1IIIB induced cytolysis in MT-4 cells, with an EC50 value of 9.60 ng·mL⁻¹. The mechanistic assay showed that wikstroelide M targeted HIV-1 reverse transcriptase and nuclear translocation of integrase through disrupting the interaction between integrase and LEDGF/p75. CONCLUSION: Wikstroelide M may be a potent HIV-1 and HIV-2 inhibitor, the mechanisms of action may include inhibition of reverse trascriptase activity and inhibition of integrase nuclear translocation through disrupting the interaction between integrase and LEDGF/p75.

Anti-HIV-1 tigliane diterpenoids from Excoecaria acertiflia Didr.

Three tigliane-type diterpenoids named excoecafolins A-C and two daphnane-type diterpenoids named excoecafolins D and E, together with 13 known compounds, were isolated from the EtOAc extract of Excoecaria acerifolia Didr. Their structures were elucidated through the analysis of the spectroscopic data. The anti-HIV-1 activity evaluation of five of these compounds showed that four possessed moderate anti-HIV-1 activities with EC50 0.258, 0.036, 0.046, and 0.978 µM, SI >1,836.9, 431.1, 298.7, and >503.7, respectively. Additionally, the chemotaxonomic issue of the affinity correlation between Thymelaeceae and Euphorbiaceae is discussed based on the isolates.

Terpenoids and their anti-HIV-1 activities from Excoecaria acerifolia.

Five new diterpenoids named excocarinols A-E (1-5) including three pimaranes, one cleistanthane, and one nor-beyerane, together with nine known compounds, were isolated from the EtOAc extract of the Chinese ethnodrug Gua-jing-ban (Excoecaria acerifolia Didr.). Their structures were elucidated by the analysis of spectroscopic data including 1D, 2D NMR and HR-MS. The anti-HIV-1 bioassay on the diterpenoids showed that excocarinol A (1) exhibited moderate anti-HIV-1 activity with EC50 5.58 µM and SI (Selection Index) over 112.71.

Lanostane triterpenoids with cytotoxic activities from the fruiting bodies of Ganoderma hainanense.

Twelve lanostane triterpenoids (1-12) including a new one 16α,26-dihydroxylanosta-8,24-dien-3-one (1) were isolated from the fruiting bodies of Ganoderma hainanense. The structure of the new compound was elucidated by 1D and 2D NMR and MS spectroscopic analyses. All isolates were evaluated for their cytotoxicities against human tumor cell lines K-562, SMMC-7721, and SGC-7901 and five compounds (1, 2, 5,7, and 9) showed definite cytotoxicities against K-562 cell line. Meanwhile, compounds 2, 5,7, and 9 exhibited cytotoxic activities against SMMC-7721 and SGC-7901 cell lines.

Three new isopimarane diterpenoids from Excoecaria acerifolia.

Three new isopimarane diterpenoids named excoecarins F-H (1-3) were isolated from the EtOAc extract of the Chinese ethnodrug Gua-jing-ban (Excoecaria acerifolia Didr.). Their structures were elucidated by the analysis of spectroscopic data including 1D, 2D NMR and HR-MS. The anti-HIV-1 bioactivity test of 1 and 2 showed weak activity.

[Chemical constituents from Daphne acutiloba].

OBJECTIVE: To study the chemical constituents from Daphne acutiloba. METHOD: The constituents were separated by column chromatography, and their structures were elucidated by spectroscopic data analyses. RESULT: Fifteen compounds were isolated from the EtOAc extract and identified as wikstroelide M (1), vesiculosin (2), prostratin (3), 7-hydroxy-coumarin (4), 7,8-di-hydroxy-coumarin (5), isodaphnoside (6), daphnorine (7), rutamontine (8), daphnolin (9), daphneticin (10), (+)-pinoresinol-beta-D-glucoside (11), oleodapnone (12), oleodaphnal (13), ergosterol peroxide (14) and cholest-5-en-3beta-ol (15). CONCLUSION: All the compounds except for 4, 5 and 14 were obtained from the stems of this plant for the first time.

Chemical constituents from the fungus Amauroderma amoiensis and their in vitro acetylcholinesterase inhibitory activities.

One new compound named amauroamoienin (1), together with thirteen known compounds (2-14), was isolated from the EtOAc extract of Amauroderma amoiensis. The structures of these compounds were elucidated by the analysis of 1D and 2D spectroscopic data and the MS technique. The bioassays of inhibitory activities of these isolates against acetylcholinesterase were evaluated, and compounds 1, 3, and 5 exhibited acetylcholinesterase inhibitory activities.

Three new sesquiterpenes with cytotoxic activity from Dobinea delavayi.

Three new sesquiterpenes dobinins A-C (1-3), together with five known compounds, were isolated from the root of Dobinea delavayi. The structures of the three new compounds were determined on the basis of spectroscopic analysis including 1D-, 2D-NMR and MS techniques as well as by comparison of the spectral data with those of analogous compounds reported in the literatures. Compounds 1-3 were screened for antitumor activity in vitro and exhibited definite cytotoxic activity against the human tumor cell line HL-60 with IC50 levels of 8.0 × 10-5, 4.7 × 10-5, and 5.1 × 10-5 M, respectively.

Two new daucane sesquiterpenoids from Daphne aurantiaca.

Two new daucane sesquiterpenoids 1ß,2ß-epoxy-10(H)α-dauca-11(12)-ene-7α,14-diol and 1α,2α-epoxy-10(H)α-dauca-11(12)-ene-7α,14-diol were isolated from the plateau medicinal plant Daphne aurantiaca Diels. (Thymelaeceae). Their structures were elucidated by 1D and 2D NMR spectroscopy, as well as HR-ESI-MS data.