Polyacetylenes and anti-hepatitis B virus active constituents from Artemisia capillaris

Three new polyacetylenes, 8-(Z)-decene-4, 6-diyne-1, 3, 10-triol (1), 1, 3S, 8S-trihydroxydec-9-en-4, 6-yne (2), 3S, 8S-dihydroxydec-9-en-4, 6-yne 1-O-β -D-glucopyranoside (3), and one new glucosyl caffeoate, 1-O-ethyl-6-O-caffeoyl-β -D-glucopyranose (4), together with 34 known compounds were isolated from Artemisia capillaris. The structures of the new compounds were determined by extensive spectroscopic analyses including 1D and 2D NMR, HRESIMS, [α]_D and CD experiments. Among them, 19 compounds showed activity inhibiting HBsAg secretion; 20 compounds showed activity inhibiting HBeAg secretion; and 25 compounds possessed inhibitory activity against HBV DNA replication according to our anti-HBV assay on HepG 2.2.15 cell line in vitro. The most active compound 12 could inhibit not only the secretions of HBsAg and HBeAg, but also HBV DNA replication with IC₅₀ values of 15.02 μM (SI = 111.3), 9.00 μM (SI = 185.9) and 12.01 μM (SI = 139.2).     

Desmodeleganine,a new alkaloid from the leaves of Desmodium elegans as a potential monoamine oxidase inhibitor

Desmodeleganine (1), a new potential monoamine oxidase inhibitor, along with three known alkaloids, bufotenin (2), hydroxy-N, N-dimethyltryptamine N¹²-oxide (3), 2-(5-methoxy-1H-indol-3-yl)-N, and N-dimethylethylamine (4) were isolated from the leaves of Desmodium elegans. Their structures were elucidated by IR, MS, 1D and 2D NMR spectra. 1 showed strong monoamine oxidase inhibitory activity with IC₅₀ value of 13.92 ± 1.5 μM, when the IC₅₀ value of iproniazid as a standard was 6.5 ± 0.5 μM. The molecular modeling was also performed to explore the binding mode of compounds 1, 2 at the active site of MAO-A and MAO-B.     

Five new triterpenoidal saponins from the roots of Ilex cornuta and their protective effects against H2O2-induced cardiomyocytes injury

Five new ursane-type triterpenoidal saponins (1–5), together with five known ones (6–10), were isolated from the EtOH extract of the roots of Ilex cornuta. The structures of saponins 1–5 were elucidated as 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside (1), 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside-6-O-ethyl ester (2), 19α-hydroxyurs-12-en-28-oic acid 3β-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranoside (3), 3β-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranosyl]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (4) and 3β-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranoside-6-O-methyl ester]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (5), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and chemical reactions. Protective effects of compounds 1–10 against H₂O₂-induced H9c2 cardiomyocyte injury were tested. Compounds 1–5, 7, and 10 showed cell-protective effects. Among them compound 5 exhibited the highest activity. No significant DPPH radical scavenging activity was observed for compounds 1–10.     

Chemical constituents of Swertia yunnanensis and their anti-hepatitis B virus activity

Four new triterpenoids, sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4), along with nineteen known compounds (5–23) were isolated from Swertia yunnanensis. Based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR, [α]_D), the structures of sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4) were elucidated as taraxer-14-ene-3α,6β-diol, oleanolic acid 28-O-β-d-glucopyranosyl-(1 → 2)-O-β-d-glucopyranoside, 2α,3β-di-hydroxyolean-12-en-28-oic acid 28-O-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl (1 → 6)-β-d-glucopyranosyl(1 → 2)-β-d-glucopyranoside and hederagenin 28-O-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl(1 → 6)-β-d-glucopyranosyl(1 → 2)-β-d-glucopyranoside, respectively. Twenty-two compounds were evaluated for their anti-HBV activities on the HepG 2.2.15 cell line in vitro, of which nine compounds showed potent anti-HBV activities. Compounds 1, 5–6, 14–16 and 19 showed activities against the secretion of HBsAg (IC₅₀ values from 0.10 to 1.76 mM) and HBeAg (IC₅₀ values from 0.04 to 1.41 mM), and compounds 11 and 13–16 exhibited significant inhibition on HBV DNA replication (IC₅₀ values from 0.01 to 0.09 mM).     

Sesquiterpenes from the rhizomes of Alpinia japonica and their inhibitory effects on nitric oxide production

A novel norsesquiterpene (1), three new bisabolenes sesquiterpenes (2–4), along with 7 known compounds (5–11), were isolated from the rhizomes of Alpinia japonica. The structures of the new compounds were elucidated by analysis of spectroscopic data. The absolute configuration of C-1 in 3 was deduced via the circular dichroism data of the in situ formed [Rh₂(OCOCF₃)₄] complexes. Inhibitory effects of the isolates on nitric oxide production in lipopolysaccaride-activated RAW264.7 macrophages were evaluated. Compound 6 showed significant inhibitory activity with IC₅₀ value of 5.3 μΜ, and compounds 1, 3, 5 and 7–10 exhibited moderate inhibitory activities with IC₅₀ values between 24.5 and 46.3 μM.     

Isolation,characterization and acetylcholinesterase inhibitory activity of alkaloids from roots of Stemona sessilifolia

Two new alkaloids, named stenine A (1) and stenine B (2), along with the known compounds neostenine (3), stenine (4) and neotuberostemonine (5), were isolated from the roots of Stemona sessilifolia. Their structures were elucidated by 1D- and 2D-NMR spectra and X-ray single-crystal diffraction experiment. Anti-acetylcholinesterase (AChE) activity of compounds 1–5 were also tested. Compounds 2 and 4 showed significant anti-acetylcholinesterase activities, with IC₅₀ values of 2.1 ± 0.2 μM and 19.8 ± 2.5 μM, resp. The mode of AChE inhibition by Compound 2 (the most potential AChE inhibitor) was reversible and competitive. In addition, molecular modeling was performed to explore the binding mode of compound 2 with AChE.     

Sesquiterpene coumarin and sesquiterpene chromone derivatives from Ferula ferulaeoides (Steud.) Korov.

Five novel compounds — three sesquiterpene coumarin derivatives, ferulin A (1), B (2), and C (3), and two sesquiterpene chromone derivatives, ferulin D (4) and E (5), together with eleven known compounds (6–16) have been isolated from the roots of Ferula ferulaeoides (Steud.) Korov. Their structures were established by comprehensive spectroscopic analysis. The biosynthetic pathways leading to these compounds were proposed. The cytotoxicity of all these isolates against HepG2, MCF-7, and C6 cancer cell lines was evaluated and compound 7 displayed the highest potency against HepG2, MCF-7, and C6 with IC₅₀ values 39.9 μM, 37.7 μM, and 16.0 μM, respectively.     

Sibiricasaponins A–E,five new triterpenoid saponins from the aerial parts of Polygala sibirica L.

Five new triterpenoid saponins, named as sibiricasaponins A–E (1–5), were isolated and identified from the aerial parts of Polygala sibirica L., together with nine known triterpenoid saponins (6–14). The chemical structures of the five new triterpenoid saponins (1–5) were elucidated as 3β,19α-dihydroxyurso-12-ene-23,28-dioic acid 3-O-β-d-glucuronopyranoside (1), pomolic acid 3-O-(3-O-sulfo)-α-l-arabinopyranoside (2), pomolic acid 3-O-(4-O-sulfo)-β-d-xylopyranoside (3), pomolic acid 3-O-(2-O-acetyl-3-O-sulfo)-α-l-arabinopyranoside (4), and 3-O-β-d-glucopyranosyl medicagenic acid 28-O-β-d-galactopyranosyl (1 → 4)-β-d-xylopyranosyl (1 → 4)-α-l-rhamnopyranosyl (1 → 2)-(4-O-acetyl)-[β-d-apiofuranosyl (1 → 3)]-β-d-fucopyranosyl ester (5), respectively, on the basis of spectroscopic data and physicochemical evidences. These isolated compounds (1–14) were evaluated for their anti-ischemic effects on oxygen/glucose deprivation (OGD) model in vitro, and only compound 7 showed a weak anti-ischemia effect, with EC₅₀ value of 46.7 μM.     

Iridoid and bis-iridoid glucosides from the fruit of Gardenia jasminoides

Three new iridoid glucosides, 6″-O-trans-feruloylgenipin gentiobioside (1), 2′-O-trans-caffeoylgardoside (2), jasmigeniposide A (3), and one new bis-iridoid glucoside, jasmigeniposide B (4), along with six known analogues (5–10), were isolated from the fruit of Gardenia jasminoides. Their structures were established on the basis of spectroscopic analyses and chemical methods. Anti-virus activity of isolated compounds were evaluated in vitro and only compound 9 showed moderate inhibitory activity against H1N1 with 50% effective concentration (EC₅₀) value of 104.36 μM, and selective index (SI) value greater than 4.79.     

New α-glucosidase inhibitors with p-terphenyl skeleton from the mushroom Hydnellum concrescens

The purpose of this study is to elucidate the bioactive components responsible for the the α-glucosidase inhibitory activity detected in the EtOAc extract of the mushroom Hydnellum concrescens. Two new p-terphenyl derivatives, concrescenins A (1) and B (2), in along with six known compounds thelephantins L (3), I (4), J (5), K (6), dihydroauran-tiacin dibenzoate (7), and curtisian A (8) were isolated from the fruiting bodies of H. concrescens. Their chemical structures were elucidated by NMR experiments. Compounds 1–4 and 6–8 showed the inhibitory activity against α-glucosidase with the IC₅₀ of 0.99, 3.11, 4.53, 18.77, 2.98, 5.16, and 8.34 μM, respectively. Kinetic analysis of α-glucosidase indicated that compounds 1 and 2 inhibited the activity of α-glucosidase in a noncompetitive fashion with a Ki value of 0.02 and 0.21 μM, respectively. In antioxidant evaluation, compounds 1 and 4 showed weak DPPH scavenging activity (EC₅₀ = 82.50 and 161.75 μM) and weak reducing ability (EC₅₀ = 193.57 and 152.94 μM). The current research supports the potential use of mushroom-derived p-terphenyl derivatives for the treatment of diabetes.     

New cytotoxic compounds from flowers of Lawsonia inermis L.

Three new compounds, a bicoumarin A (1), a biflavonoid A (2), and a biquinone A (3), as well as 12 other known compounds, were isolated from the flower of Lawsonia inermis L. The structures were elucidated by spectral analysis and new compounds 2 and 3 then were further confirmed by ECD calculations and single-crystal X-ray diffraction crystallography respectively. The cytotoxicity of the compounds against four cancer cell lines, including MCF-7, Hela, HCT-116, and HT-29 were evaluated using MTT assay. The IC₅₀ values of compounds 3 and 5 against MCF-7, Hela, HCT-116, and HT-29 were 2.24, 1.42, 24.29, and 7.02 μM and 6.1, 2.44, 5.58, and 10.21 μM respectively. The two compounds exhibited stronger inhibitory activities than the positive control 5-fluorouracil (IC₅₀ = 7.34, 11.50, 36.17, 18.83 μM) against the four tested cell lines. These results demonstrated that compounds from the flowers of L. inermis L. showed cytotoxic activity on MCF-7, Hela, HCT-116, and HT-29 cell lines.     

Carapanolides C–I from the seeds of andiroba (Carapa guianensis,Meliaceae)

Five new mexicanolide-type limonoids, carapanolides C–G (1–5), together with two new phragmalin-type limonoids, carapanolides H–I (6, 7), were isolated from the oil of Carapa guianasis AUBLET (Meliaceae) seeds. Their structures were elucidated on the basis of spectroscopic analyses using 1D and 2D NMR spectra and FABMS. Carapanolides C (1), E (3), and I (7) exhibited moderate activity in the P388 (IC₅₀ 17.9 μM in 1, 15.8 μM in 3) and L1210 cell lines (IC₅₀ 13.3 μM in 1, 18.1 μM in 3, 16.9 μM in 7). On the other hand, Carapanolide D (2) exhibited a strong inhibitory effect in the HL-60 cell line (IC₅₀ 11.0 μM), Carapanolides F (4) showed inhibitory activity in the L1210 cell line (IC₅₀ 15.9 μM), and the cytotoxic activity of Carapanolides I (7) was moderate in all cell lines.     

Cyclodepsipeptides from the ascocarps and insect-body portions of fungus Cordyceps cicadae

A new cyclodepsipeptide cordycecin A (1), together with four known ones beauvericin E (2), beauvericin J (3), beauvericin (4), and beauvericin A (5) was isolated from the ascocarps and insect-body portions of fungus Cordyceps cicadae. Their structures were identified by NMR and MS analyses. The absolute configuration of 1 was confirmed by crystal X-ray diffraction. Compounds 2–5 exhibited a significant inhibitory effect on HepG2 and HepG2/ADM cells with IC₅₀ values ranging from 2.40 ± 0.37 to 14.48 ± 1.68 μM. Interestingly, compounds 3–5 showed cytotoxic activity against multiple drug resistant HepG2 cell line (HepG2/ADM) with IC₅₀ value 25-fold more sensitive to doxorubicin.     

Cytotoxic and anti-inflammatory ent-kaurane diterpenoids from Isodon wikstroemioides

Seven new ent-kaurane diterpenoids, isowikstroemins A–G (1–7), were isolated from EtOAc extracts of the aerial parts of Isodon wikstroemioides. Their structures were elucidated by extensive spectroscopic analysis. The isolates were evaluated for their cytotoxicity against five human tumor cell lines, and compounds 1–4 exhibited significant activity with IC₅₀ values ranging from 0.9 to 7.0 μM. In addition, compounds 1, 2, 3, 4, and 7 exhibited inhibitory activity against nitric oxide (NO) production in LPS-activated RAW264.7 macrophages.     

Three new phenolic compounds from the leaves of Rosa sericea

Two new flavonoids, quercetin-3-O-β-d-xylopyranosyl-(1 → 2)-α-d-ribopyranoside (1) and kaempferol-3-O-β-d-xylopyranosyl-(1 → 2)-α-d-ribopyranoside (2), and one new phenolic derivative, gallicin-p-O-(6′-O-caffeoyl)-β-d-glucoside (3), together with twelve known compounds were isolated from the leaves of Rosa sericea (Rosaceae family). The structures of the new compounds were established by means of spectroscopic analysis including one- and two-dimensional NMR spectroscopy. Some of the isolated compounds were tested for the cytotoxicity of a breast cancer cell (MCF-7) line. The results showed that rubanthrone A (4) has moderate cytotoxicity against the MCF-7 cell line.     

Cycloartane Triterpenes from Beesia calthaefolia (Maxim.)

Three new cycloartane triterpenoids (1–3) and two known compounds (4, 5) were isolated from the whole plant of Beesia calthaefolia. Their structures were elucidated by 1D and 2D NMR, HRESIMS and optical rotation spectral data. All isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 4 showed stronger inhibitory activity (IC₅₀ 136.7 μM) than positive control (Rosmarinic acid, IC₅₀ 181.8 μM) while compounds 2 and 3 were moderately active with IC₅₀ value of 206 μM and 200.9 μM. Chemical compound studied in this article: Rosmarinic acid (PubChem CID: 5281792).     

Four new C18-diterpenoid alkaloids with analgesic activity from Aconitum weixiense

Four new C₁₈-diterpenoid alkaloids, weisaconitines A–D (1–4), were isolated from Aconitum weixiense. Based on extensive UV, IR, MS, 1D and 2D NMR analyses, their structures were elucidated as 8-O-ethyldolaconine (1), 4-demethylgenicunine B (2), 14-oxoaconosine (3), and 8-O-ethylaconosine (4). The analgesic activity of compound 4 was studied with CH₃COOH-induced writhing model in mice. Compound 4 showed writhing inhibitions of 24% (50 mg/kg), 26% (100 mg/kg) and 34% (200 mg/kg), respectively, as compared to the reference drug aspirin (63%) at a dose of 200 mg/kg.     

Bioactive cis-stilbenoids from the tubers of Scirpus yagara

Two new cis-stilbenoids, sciryagarol I (1) and II (2) were isolated from the EtOAc extract of the tubers of Scirpus yagara, together with four known compounds. The structures of all compounds were determined by comprehensive analyses of their spectroscopic data and comparison with literature information. The compounds 3, 4 and 6 were isolated for the first time from this genus. Some compounds were tested for their cytotoxicity against human tumor cell lines and antimicrobial activity. Compounds 1–4 showed significant cytotoxicity against the Hela cell lines with IC₅₀ values ranging from 7.21 to 61.21 μM. 1 and 2 exhibited some antimicrobial activity against Staphylococcus aureus and Candida albicans with uniform MICs of 79.3 μl/ml for 2, and 152 μl/ml for 1, respectively.     

Biotransformation on the flavonolignan constituents of Silybi Fructus by an intestinal bacterial strain Eubacterium limosum ZL-II

Eubacterium limosum ZL-II is an anaerobic bacterium with demethylated activity, which was isolated from human intestinal bacteria in our previous work. In this study, the flavonolignan constituents of Silybi Fructus were biotransformed by E. limosum¹ ZL-II, producing four new transformation products — demethylisosilybin B (T1), demethylisosilybin A (T2), demethylsilybin B (T3) and demethylsilybin A (T4), among which T1 and T2 were new compounds. Their chemical structures were identified by ESI-TOF/MS, ¹H NMR, ¹³C NMR, HMBC and CD spectroscopic data. The bioassay results showed that the transformation products T1–T4 exhibited significant inhibitory activities on Alzheimer's amyloid-β 42 (Aβ₄₂²) aggregation with IC₅₀ values at 7.49 μM–10.46 μM, which were comparable with that of the positive control (epigallocatechin gallate, EGCG³, at 9.01 μM) and much lower than those of their parent compounds (at not less than 145.10 μM). The method of biotransformation by E. limosum ZL-II explored a way to develop the new and active lead compounds in Alzheimer's disease from Silybi Fructus. However, the transformation products T1–T4 exhibited decreased inhibitory activities against human tumor cell lines comparing with their parent compounds.     

Antibacterial prenylbenzoic acid derivatives from Anodendron formicinum

A phytochemical investigation on the stems of Anodendron formicinum led to the isolation of eight prenylbenzoic acid derivatives. Three of these were new compounds, designated as formicinuosides A (1), B (2), and C (3). Their structures were elucidated on the basis of extensive spectroscopic analysis, as well as by comparison with the reported spectroscopic data. This is the first report of chemical constituents from A. formicinum and their antimicrobial activities. Among the isolated compounds, compounds 4, 6 and 8 showed significant antibacterial activities against Providensia smartii with MIC values of 0.781 μg/mL. Moreover, compound 8 showed remarkable antibacterial activity against Escherichia coli with MIC value of 0.781 μg/mL.