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Two new dimeric 2-(2-phenethyl)chromones (filarones A and B) were isolated from agarwood of Aquilaria filaria (Thymelaeaceae) by LC–MS-guided fractionation procedure. Their structures were established based on spectroscopic methods including HRESIMS, one and two dimensional NMR. Filarones A and B exhibited significant inhibition of nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells with IC50 values of 11.33 ± 1.76 μM and 10.69 ± 0.18 μM. Quercetin and indomethacin were used as positive controls with IC50 values of 8.22 ± 0.80 μM and 35.40 ± 1.77 μM, respectively.

Three new aromadendrane-type sesquiterpenoids (1–3) and five known compounds (4–8) were isolated from the stems of Strophanthus divaricatus. Their structures were determined by spectroscopic methods including HR-ESI-MS, 1D and 2D NMR. The absolute configurations of 1–3 was determined by comparison of the experimental and computed ECD spectra. Neridienone A (6) exhibited significant cytotoxicity against human cancer cell lines BEL-7402, SGC-7901, K562, A549, and HeLa with IC50 values of 3.30 ± 0.01, 2.25 ± 0.01, 2.02 ± 0.03, 1.55 ± 0.01, 4.73 ± 0.07 μM, respectively.

Chemical investigation on the cultures of the fungus Marasmius berteroi, resulted in the isolation of 10 compounds including 2 new ones named (S)-3,7-dihydroxy-1-indanone (1) and (S)-3-hydroxy-4-methoxy-3-methyl isobenzofuran-1(3H)-one (2). Their structures were determined based on NMR, HRESIMS and ECD spectra analysis. Compounds 5-6, 10 revealed moderate inhibitory activity against the nematode Panagrellus redivivus with mortality ratio of 95 %, 85 %, and 75 % at 2.5 mg/mL, respectively.

Two new compounds, dendronobilate (1) and 4-O-demethyl-nobilone (2), together with one known fluorenone were isolated from the aerial parts of Dendrobium nobile Lindl. Their structures were characterized by detailed analysis of 1D and 2D NMR spectra, HRESIMS and ECD spectra. Compounds 1–3 showed significant α-glucosidase inhibitory activity with IC50 values of 27.46 ± 3.14, 4.52 ± 0.33, and 10.78 ± 2.05 μM, respectively, which were superior to the acarbose (745.9 ± 3.3 μM). The binding interactions of 1 and 2 with α-glucosidase were investigated using molecular docking simulations. In addition, compound 2 exhibited potent inhibitory effect on NO production in LPS activated RAW264.7 cells with the IC50 value of 35.40 ± 1.77 μM without cytotoxicity observed.

Three new triterpenoids (1–3), including two new 19 (10 → 9β) abeo-tirucallane derivatives (1–2) and a new tirucallane-type triterpenoid (3), together with two known tirucallane-type triterpenoids (4–5) were isolated from the ethanol extract of the fruits of Chukrasia tabularis. Their structures were elucidated on the basis of 1D and 2D NMR spectroscopic analyses and MS data. The isolated triterpenoids 1 and 2 exhibited anti-inflammatory activities with IC50 values of 75.98 ± 2.12 and 24.86 ± 1.16 μM, respectively. Compound 5 showed cytotoxic activities against the selected tumor cell lines.

Two new 2-(2-phenethyl)chromone derivatives were isolated from agarwood of Aquilaria walla, including a dimeric 2-(2-phenethyl)chromone (1) and a flavonoid-2-(2-phenethyl)chromone (2). Their structures were established based on spectroscopic methods including HRESIMS, 1D, and 2D NMR. Compounds 1 and 2 showed cytotoxic activity against five human cancer cell lines with IC50 values ranging from 4.96–44.34 μM.

Four eudesmane sesquiterpene glycosides named pulisignoside A (1), B (2), C (3), and D (4) were isolated in addition to lemmonin C (5) from the Tibetan folk medicine Ming·chen·serpo (Pulicaria insignis Drumm. ex Dunn). Structures of these compounds were elucidated by comprehensive analyses of MS, 1D NMR, and 2D NMR spectroscopic data. In the anti-nematodal bioassays, pulisignoside C (3) showed nematocidal activity against Meloidogyne incognita (IC50 25.42 ± 0.28 μM).

Two new cyclic diarylheptanoids, casuaritriol A (1) and casuaritriol B (2), were isolated from the EtOAc extract of litters (including branches and leaves) of Casuarina equisetifolia, along with a new triterpene casuariene (3), and two known compounds diarylheptanoids adanin (4) and ostryopsitriol (5). Their structures were elucidated by spectroscopic analysis (including HRESIMS, 1D NMR and 2D NMR data), and the absolute configuration of 3 was determined by analysis of the ECD data according to the octant rule. Compound 1 exhibited inhibitory activity against α-glycosidase with inhibition rate of 45.1 ± 1.4 % at a concentration of 500 μg/mL. In addition, compound 4 showed weak inhibitory activity against acetyl cholinesterase (AChE) with inhibition rate of 14.9 ± 1.1 % at a concentration of 50 μg/mL.

Two new alkaloids (1–2), and four known ones (3–6) were isolated from branches of Cephalotaxus hainanensis Li. The structures of new alkaloids were elucidated by extensive analysis of HRESIMS, 1D and 2D NMR data. The absolute configuration of compound 2 was established on the basis of experimental and computed ECD data. All compounds were evaluated for their cytotoxic activity against K562, BEL-7402, SGC-7901, A549, and Hela human cancer cell lines. Compound 6 exhibited significant activity with IC50 values ranging from 4.86 to 26.56 μM, respectively.

In our ongoing effort to study the metabolites from agarwood of Aquilaria crassna Pierre ex Lecomte (Thymelaeaceae) produced in Laos, three new 2-(2-phenylethyl)chromone derivatives (1−3) were isolated. Their structures were elucidated by comprehensive spectroscopic analyses, predominantly by 1D and 2D NMR spectroscopic methods, and by comparison with the reported data. Compound 2 exhibited tyrosinase inhibitory activity with IC50 value of 172.6 ± 1.7 μM (kojic acid as the positive control, 46.1 ± 1.3 μM) and its inhibition mode was clarified by molecular modelling study. None of the isolates showed significant cytotoxicity towards tested cancer cell lines.

One new 2-(2-phenylethyl)chromone (1), three new naturally occurring 2-(2-phenylethenyl)chromones (3–5), together with a known 2-(2-phenylethyl)chromone (2) were isolated from the EtOH extract of agarwood originating from Aquilaria crassna in Cambodia. Their structures were unambiguously elucidated by detailed spectroscopic (NMR, UV, IR, MS) analyses. All the compounds were tested for acetylcholinesterase (AChE) inhibitory activity and cytotoxicity against tumor cell lines (K562, BEL-7402, SGC-7901 and Hela). Compound 1 displayed weak AChE inhibitory activity (inhibitory ratio: 35.0 ± 2.19%) and cytotoxicity against K562 tumor cell line (IC50: 40.81 ± 0.64 μM). Along with, compound 3 showed cytotoxicity against BEL-7402 tumor cell line (IC50: 44.18 ± 0.34 μM).

Three new 2-(2-phenylethyl)chromone derivatives ( 1 – 3 ) were obtained from the artificial holing agarwood originating from Aquilaria sinensis . Their structures were unambiguously deduced by detailed spectroscopic analysis and the absolute configurations were determined by ECD calculations. Compounds 1–3 displayed acetylcholinesterase (AChE) inhibitory activity with the inhibition ratios in the range of 30%–45% at a concentration of 50 μg/ml.

Three previously undescribed eudesmane-type sesquiterpenoids penicieudesmols E-G were obtained from the endophytic fungus Penicillium sp. J-54 isolated from the leaves of mangrove plant Ceriops tagal. The structures of the new compounds were unambiguously elucidated by 1D and 2D NMR, and by HREIMS, as well as by comparison with the literature. Bioactivities results showed that compound 2 presented α-glucosidase inhibitory activity.

Three new drimane-type sesquiterpenoids named xylariaines A–C (1–3), together with one known analogue (4), were isolated from the ethyl acetate extract of cultures of the fungus Xylaria polymorpha (Pers.: Fr.) Grer. Their structures were elucidated unambiguously by NMR and single-crystal X-ray diffraction analysis. Compounds 1 and 2 exhibited weak anti-acetylcholinesterase activities at a concentration of 50 μg/mL with inhibition ratios of 12.4% and 18.0%, respectively.

Two new phenolic bisabolane sesquiterpenes, asperchondols A (1) and B (2), together with seven known analogues (3-9) and four known diphenyl ethers (10-13) were obtained from Aspergillus sp., that had been isolated from the marine sponge Chondrilla nucula. Their structures were elucidated through NMR and MS analysis, and by comparison with literature data. All isolated compounds were evaluated for their antibacterial activity against eight human pathogenic bacteria. Co-cultivation experiment of Aspergillus sp. with Bacillus subtilis was also conducted. (C) 2016 Phytochemical Society of Europe. Published by Elsevier Ltd. All rights reserved.

Two new guaiane sesquiterpenes (1⿿2), one new acorane sesquiterpene (3), along with two known sesquiterpenes (4⿿5) were isolated from high quality agarwood ⿿Qi-Nan⿿ originating from Aquilaria sinensis. Their structures were established based on spectroscopic methods including IR, HRESIMS, 1D, and 2D NMR. Compound 1 was a guaiane sesquiterpene lactone, and compound 2 was a guaiane sesquiterpene with a 5/6/7 ring carbon skeleton. Compounds 3 and 4 were acorane-type sesquiterpenes. The two acorane sesquiterpenes (3⿿4) possess lasting fragrant smell at room temperature. These isolated guaiane and acorane sesquiterpenes showed acetylcholinesterase inhibitory activities in different degrees ranged from 19% to 44% at the concentration of 50 μg/mL.

Five new compounds named penicillars A⿿E were isolated from the fermentation broth of Penicillium sp. SCS-KFD08 associated with the marine animal Sipunculus nudus from the Haikou bay of China. Their planar structures and absolute configurations were unambiguously elucidated by spectroscopic data, Mo2(OAc)4 induced CD spectrum analysis along with quantum ECD calculation. Among them, compounds 2 and 3, at a concentration of 50 μg/mL, showed weak inhibitory activity against AChE with inhibition rates of 19.5% and 21.3%, respectively.

The soil-dwelling fungus Aspergillus terreus was isolated from sediment collected from the lake of Wadi EI Natrun in Egypt. Co-cultivation of A. terreus with the bacteria Bacillus subtilis and Bacillus cereus on solid rice medium resulted in an up to 34-fold increase in the accumulation of constitutively present fungal natural products (4–15) compared to axenic cultures of A. terreus. The fungal products included two new butyrolactone derivatives, isobutyrolactone II (1) and 4-O-demethylisobutyrolactone II (2), together with the known N-(carboxymethyl)anthranilic acid (3) that were not present in axenic fungal controls and were only detected during co-cultivation with B. subtilis or with B. cereus. The structures of all compounds were unambiguously elucidated by 1D and 2D NMR spectroscopy, and by HRESIMS measurements, as well as by comparison with the literature. In a second set of experiments, A. terreus was co-cultured with Streptomyces lividans and with Streptomyces coelicolor. These co-cultivation experiments failed to induce fungal natural product accumulation in contrast to co-cultures with Bacillus sp. Compounds 5 and 14 showed weak inhibition of B. cereus with minimal inhibitory concentrations (MICs) of 64 μg/mL, whereas only 8 showed moderate cytotoxicity against the murine lymphoma (L5178Y) cell line with inhibition of 80% at a dose of 10 μg/mL.

Six new phenolic compounds ( 1 – 6 ), along with five known phenolics ( 7 – 11 ) were isolated from the heartwood of Dalbergia odorifera T. Chen. (Leguminosae). Their structures were determined by spectroscopic techniques including MS, UV, IR, 1D and 2D NMR. Bioassay results showed that compound 1 exhibited cytotoxicity against SGC-7901 and BEL-7402 tumor cell lines, while compounds 3 , 5 and 10 showed antibacterial activities against Ralstonia solanacearum .

Four new bibenzyl derivatives, named dendrosinens A–D (1–4), together with twelve known phenolic compounds were isolated from the whole plant of Dendrobium sinense T. Tang et F. T. Wang, an endemic and endangered orchid in Hainan Island, PR China. Their structures were elucidated by 1D, 2D NMR (HMBC, HMQC, COSY and NOESY), and HREIMS analyses. Bioassay results demonstrated that compounds 5–8 showed cytotoxic activity.

Phytochemical analysis of the high quality Chinese agarwood ‘Qi-Nan’ originating from Aquilaria sinensis (Lour.) Glig, led to the isolation of four fragrant sesquiterpenes, including an agarofuran 4-hydroxyl-baimuxinol ( 1 ) and three eremophilanes, 7 β-H -9(10)-ene-11,12-epoxy-8-oxoeremophilane ( 2 ), 7 α-H -9(10)-ene-11,12-epoxy-8-oxoeremophilane ( 3 ), neopetasane ( 4 ). Among them, compounds 1 – 3 were new compounds. Their structures were elucidated by spectroscopic techniques (UV, IR, 1D and 2D NMR) and MS analyses. Eremophilane sesquiterpenes 2 – 4 showed inhibitory activities against acetylcholinesterase with IC 50 value of 274.8, 491.4, and 158.3 μM, respectively.

Two new daphnane diterpenoids, trigoxyphins J and K ( 1 and 2 ), and one new friedelane triterpene derivative, 3-O-benzoylpluricostatic acid ( 3 ), together with thirteen known terpenoids ( 4 – 16 ) were isolated from Trigonostemon xyphophylloides (Croiz.) L.K. Dai and T.L. Wu. Their structures were identified on the basis of physicochemical properties and spectroscopic data. All compounds were evaluated for their cytotoxicity against K562, SGC-7901, and BEL-7402 tumor cell lines, respectively.

Two new strophanthidol cardenolides, toxicarioside N ( 1 ) and toxicarioside O ( 2 ), together with three known ones, were isolated from the seeds of Antiaris toxicaria . The structures of the new compounds were identified as strophanthidol-3- O - β - d -glucopyranosyl-(1 → 4)-6-deoxy- β - d -allopyranoside ( 1 ) and strophanthidol-3- O - β - d -glucopyranoside ( 2 ), respectively. The cytotoxic test showed that compounds 1 and 2 exhibited significant cytotoxicity against SMMC-7721 and K562.

Phytochemical investigation of Aglaia odorata var. microphyllina led to the isolation of two new rocaglamide derivatives and three known ones. The structures of the two new compounds were elucidated as 8b-methoxy-desmethylrocaglamide ( 1 ) and 3′-hydroxy-8b-methoxy-rocaglamide ( 2 ) by spectroscopic techniques (IR, MS, 1D and 2D NMR) and comparing with published data. All the five compounds were evaluated for cytotoxic activity against K562 cell line by MTT method. The results indicated that the OH at 8b position was a decisive group for cytotoxic activity.

The bioassay-guided chemical investigation of the whole plant of Elephantopus tomentosus led to the isolation of two new germacranolides, tomenphantopin C ( 1 ) and tomenphantopin D ( 2 ), together with four known compounds ( 3 – 6 ). Their structures were determined by spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). All compounds were evaluated for cytotoxic and antibacterial activities.

Phytochemical investigation on the stems of Trigonostemon heterophyllus led to the isolation of a new diterpene, trigonoheterene ( 1 ), and a new naphthoquinone, trigonoheterone ( 2 ), together with two known compounds, 3,4-seco-sonderianol, ( 3 ) and trigonochinene E, ( 4 ). Their structures were determined by spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). All compounds were evaluated for cytotoxic activities and antibacterial activities.