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In previous studies, several isoindolin-1-one analogs that exhibited significant anti-tobacco mosaic virus (anti-TMV) activities were isolated from Nicotiana tabacum. Since gene-editing mutants provide a new sample for the discovery of active metabolites, we focused on the stems of YN-18-23 (a mutant N. tabacum for gene editing with the alkaloid metabolic pathway cultivated by Yunnan Tobacco Company), which led to the isolation of four new (1-4) and four known (5-8) isoindolin-1-ones. To the best of our knowledge, nicindole C (3) is the first subclass of isoindolin-1-one bearing a pentacyclic ketone, while nicindole D (4) is the first example of isoindolin-1-one bearing a methyl-pyridin-2-(1H)-one moiety. Compounds 1-4 were tested for their anti-TMV activities, and the results revealed that compounds 1, 3, and 4 exhibited high anti-TMV activities at concentrations of 20 μM with inhibition rates of 48.6, 42.8, and 71.5%, respectively. These rates are higher than the inhibition rate of the positive control (33.2%). The mechanistic study of compound 4, which had the highest anti-TMV activity revealed that increased potentiation of defense-related enzyme activities and downregulation of expression of the NtHsp70 protein may induce resistance in tobacco against the viral pathogen TMV. Molecular docking studies also revealed that the isoindolin-1-one substructure is fundamental for anti-TMV activity. The methyl-pyridin-2-(1H)-one moiety in compound 4 and the 2-oxopropyl groups in compounds 1 and 3 at the N-2 position may increase inhibitory activities. This study of the structure-activity relationship is helpful for finding new anti-TMV activity inhibitors. To study whether the isoindolin-1-ones have broader antiviral activities, compounds 1-4 were also tested for their anti-rotavirus activities. Compound 4 exhibited high anti-rotavirus activity with a therapeutic index (TI) value of 20.7. This TI value is close to that of the positive control (20.2).

Three new isochromenes, (5-methoxy-7-prenyl-1H-isochromen-3-yl)methanol (1), 3-(3-(hydroxymethyl)-5-methoxy-1H-isochromen-7-yl)propan-1-ol (2), and (5-methoxy-7-methyl-1H-isochromen-3-yl)methanol (3), along with three known analogues (4–6) were isolated from the fermentation products of a Nicotiana tabacum-derived endophytic fungus Aspergillus versicolor. Their structures were elucidated by spectroscopic methods, including extensive 1 D and 2 D NMR techniques. Compounds 1–3 and 6 were evaluated for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compound 2 exhibited high anti-TMV activity with inhibition rate of 46.4%, and this rate is higher than that of positive control. Compounds 1, 3, and 6 also showed potential anti-TMV activity with inhibition rates of 28.6, 30.5, and 26.2%, respectively. The IC50 of compounds 1–3 and 6 were also tested, and showed IC50 values of 49.3, 22.4, 42.2, and 54.1 µM, respectively.

The structural derivatization of the fungal meroditerpenoid chevalone E was achieved by biocatalytic and chemical approaches. Some of the new chevalone analogues, in combination with doxorubicin, synergistically inhibit the growth of breast cancer cells.

Two new isobenzofuranone derivatives (1 and 2) together with six known compounds (3–8) were isolated from the roots of Phlomis betonicoides, a highly sweet plant in China. Their structures were determined by means of HR-ESI-MS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1–8 were tested for their anti-rotavirus activity. The results showed that compounds 1–8 exhibited potent anti-rotavirus activity with therapeutic index value 7.5–16.4.

Two new naphthalene derivatives, 1-(3-hydroxy-1-(hydroxymethyl)-2-methoxy-6-methylnaphthalen-7-yl) propan-2-one (1) and 1-(3-hydroxy-1-(hydroxymethyl)-6-methylnaphthalen-7-yl)propan-2-one (2), together three known naphthalene derivatives (3–5) were isolated from the fermentation products of the endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results showed that compounds 1 and 2 showed weak inhibition with IZD of 10.2 ± 1.8 and 11.3 ± 2.0 mm, respectively.

Two new sesquiterpene aryl esters, armimelleolides A and B (1 and 2), and four known ones, were isolated from the EtOAc extract of Armillaria gallica 012 m by column chromatography on silica gel, r...

Two new tricyclic alkaloids (1 and 2), together with three known (3–5) alkaloids, were isolated from the whole plants of Thalictrum cultratum. Their structures were determined by means of HR-ESI-MS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1–5 were tested for their anti-rotavirus activity. The results revealed that compounds 1–5 exhibited potent anti-rotavirus activity with therapeutic index (TI) values in the range 10.7–17.7.

Two new diphenyl ethers (1 and 2) were isolated from the fermentation products of an endophytic fungus Phomopsis asparagi. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1 and 2 showed good inhibition with IZD 10.8 ± 2.0 and 11.4 ± 1.8 mm, respectively.

Seven compounds including a new one named as 13-angeloyloxy-diplosporin (1) were isolated from the endophytic Phomopsis sp. 0391 cultivated in the presence of a histone deacetylase inhibitor. All of these isolates were evaluated for lipase suppressive activities and we firstly found that compounds cytosporone B (5) and dothiorelone A (6) displayed significant lipase inhibited activities compared to the positive control (Orlistat, IC50 = 43 μg/mL) with the IC50 values at 115 and 275 μg/mL, respectively.

Two new diphenyl ethers, 1-[2-methoxy-4-(3-methoxy-5-methylphenoxy)-6-methylphenyl]-ethanone (1) and 1-[4-(3-(hydroxymethyl)-5-methoxyphenoxy)-2-methoxy-6-methylphenyl]-ethanone (2), together five known diphenyl ether derivatives (3–7), were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. Compounds 1 and 2 showed good inhibition with IZD of 13.8 ± 1.5 mm and 14.6 ± 1.6 mm, respectively.

A biosynthetic gene cluster for chevalone E (1) and its oxidized derivatives have been identified within the genome of the endophytic fungus Aspergillus versicolor 0312, by a mining strategy targeting a polyketide-diterpenoid hybrid molecule. The biosynthetic pathway has been successfully reconstituted in the heterologous fungus Aspergillus oryzae. Interestingly, two P450 monooxygenases, Cle2 and Cle4, were found to transform 1 into seven new analogues including 7 and 8 that possess a unique five-membered lactone ring. Furthermore, the replacement of the terpene cyclase gene with that from another fungus led to the production of sartorypyrone D (11), which has a monocyclic terpenoid moiety. Finally, some of the compounds obtained in this study synergistically enhanced the cytotoxicity of doxorubicin (DOX) in breast cancer cells.

Three new diphenyl ethers (1-3), together with four known isopentylated diphenyl ethers derivatives (4-7), were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1-3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results revealed that compounds 1 and 2 showed strong inhibitions with inhibition zone diameters (IZD) of 20.2 ± 2.5 mm and 17.9 ± 2.2 mm, respectively. Compound 3 also showed good inhibition with IZD 15.2 ± 1.8 mm. The IZD data of compound 1 is close to that of positive control with IZD 21.9 ± 2.1 mm.

Phytochemical investigation on Lepidium meyenii led to the discovery of macahydantoin C (3), a new thiohydantoin with a 1,3-diazabicyclo[3.3.1]nonane core, the spectral properties of which indicate a potential structural misassignment of its previously reported analogue, macahydantoin B (2a). To probe this hypothesis, a concise, scalable, and biomimetic synthesis of the originally proposed 2a and its revised structure (2b) was efficiently accomplished using the modified Edman degradation as the key step from commercially available materials in 65% (three steps) and 52% (three steps) overall yields, respectively. These synthetic endeavors undoubtedly reassigned the structure of macahydantoin B as an unreported type of thiohydantoin featuring a 4-methyl-hexahydropyrrolo[1,2-c]imidazole scaffold.

Three previously unreported anthraquinones, fistulaquinones A–C (1–3), together with three known ones (4–6) were isolated from the twigs of Cassia fistula. Their structures were determined by means of extensive NMR and MS spectroscopic analyses. All the isolated compounds were tested for their anti-tobacco mosaic virus (anti-TMV) activity, and compound 3 showed significant activity with inhibition rate of 34.5% at 20 μM concentration, even more potent than positive control. Additionally, compounds 1–6 exhibited moderate cytotoxicity with IC50 values ranging from 2.8 to 9.4 μM for some tested human tumor cell lines.

Several poly(arylene ether nitrile) (PAEN) copolymers containing multi-methyl and cardo xanthene groups were synthesized by nucleophilic substitution reaction of 2,6-difluorobenzonitrile with varying molar ratios of 9,9-bis(3,5-dimethyl-4-hydroxyphenyl)xanthene (BDMHPX) and hydroquinone (HQ) (80/20–40/60) in N-methyl-2-pyrrolidone (NMP) in the presence of anhydrous potassium carbonate. These new PAENs had inherent viscosities between 0.56 and 0.68 dL g–1, and their weight-average molecular weights and number-average molecular weights were in the range of 33,300–36,500 g mol−1 and 17,300–18,400 g mol−1, respectively. All polymers were amorphous and soluble in dipolar aprotic solvents such as NMP and N, N-dimethylacetamide and even in THF and chloroform at room temperature. These PAENs showed glass transition temperatures ( Tgs) between 248°C and 289°C, and the Tg values were found to increase with increase of the BDMHPX content in the polymeric main. Thermogravimetric analysis showed that all PAENs were stable up to 400°C, with 5% weight loss temperatures ranging from 427°C to 448°C and char yields of 57–61% at 700°C under nitrogen atmosphere. All new PAENs could be cast into strong and flexible films with a tensile strength of 93–115 MPa, elongation at break of 10–12%, and tensile modulus of 3.3–3.5 GPa.

Phytochemical investigations on the ethanol extract of the twigs of Garcinia tetralata resulted in the isolation of three new biphenyls, tetralatabiphenyls A-C (1-3), along with three known biphenyl derivatives (4-6). Structural elucidations of 1-3 were performed by spectroscopic methods such as 1D and 2D NMR spectra, in addition to high-resolution mass spectra. Compounds 1-6 were also evaluated for their anti-tobacco mosaic virus (anti-TMV) activity. The results showed that compound 3 showed high anti-TMV activity with inhibition rate of 31.1%. Compounds 1, 2, and 4-6 also showed modest anti-TMV activities with inhibition rates in the range of 18.9-24.5%, respectively.

The title compound (I), called perovskiaol, exhibits significant cytotoxic activity inhibiting NB4, A549 as well as HepG2 cells.

Three new tricyclic alkaloid, siamalkaloids A–C ( 1 – 3 ), together with three known alkaloids ( 3 – 6 ) were isolated from the twigs of Cassia siamea . Their structures were determined by means of HRESIMS and extensive 1D and 2D NMR spectroscopic studies. Compounds 1 – 6 were tested for their anti-tobacco mosaic virus (anti-TMV) activity, and compound 3 exhibited high anti-TMV activity with inhibition rate of 34.5%. This rate is higher than that of positive control. In addition, the cytotoxicity of compounds 1 – 6 were also tested, and compounds 2 – 6 showed weak activity with IC 50 values ranging from 2.8 to 9.4 μM for some tested human tumor cell lines.

Two novel terpenoids, named norperovskatone (1), biperovskatone (2) were isolated from the cultured Perovskia atriplicifolia, together with five known compounds. Compound 1 was a novel C18 nor-diterpenoid featuring a unique seco-ring C. Compound 2 was an unusual dimer including two different diterpenoid units. The structures of the two novel compounds were established by comprehensive spectroscopic analysis, as well as by crystal X-ray diffractions. All of the isolates were evaluated for their anti-HBV activities. Compounds 1 and 2 were found to possess remarkable anti-HBV activity.

Versicolols A and B (1 and 2), two rare prenylated isocoumarin derivatives, along with five known isocoumarins (3–7) were isolated from the fermentation products of an endophytic fungus Aspergillus versicolor. Their structures were elucidated on the basis of extensive spectroscopic analysis, including 1D- and 2D-NMR techniques. Compounds 1 and 2 were evaluated for their cytotoxicity against five human tumor cell lines. The results showed that compounds 1 exhibited weak cytotoxicity against A549 and MCF7 cells with IC50 values of 9.4 and 8.8 μm, and compound 2 exhibited weak cytotoxicity against SHSY5Y and MCF7 cells with IC50 values of 8.2 and 6.8 μm, respectively.

Comastomaxanthones A–C ( 1 – 3 ), three new xanthones with a rare 2-oxoprenyl substituent, along with three known ones ( 4 – 6 ) were isolated from the aerial parts of Comastoma pedunculatum . Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. In addition, compounds 1 – 6 were tested for their anti-tobacco mosaic virus activity. The results showed that all isolated compounds exhibited weak anti-TMV activity with IC 50 values ranging from 122.7 to 242.9 μM.

Three new isopentylated diphenyl ethers, (1–3), together with two known isopentylated diphenyl ethers derivatives (4 and 5) were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compounds 1–3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity. The results showed that compounds 1–3 showed strong activity with diameter of inhibition zone (IZD) of 21.8 ± 2.4 mm, 16.8 ± 2.2 mm, and 15.6 ± 2.0 mm, respectively.

Three new C-alkylated flavonoids, 4′-hydroxy-8-isobutyryl-7-methoxy-6-methyl-flavone (1), 4′,7-dimethoxy-8-isobutyryl-6-methyl-flavone (2), and 4′,7-dimethoxy-8-isobutyryl-flavone (3), together with three know ones luteolin (4), kaemferol (5), and quercetin (6), were isolated from Desmodium oblongum. Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D-NMR techniques. Compound 1 showed cytotoxicity against NB4, SHSY5Y, and MCF7 cell lines with IC50 values of 8.5, 6.5, and 7.8 μM; compound 2 showed cytotoxicity against SHSY5Y and PC3 cell lines with IC50 values of 5.0 and 6.8 μM; compound 3 displayed cytotoxicity against SHSY5Y and MCF7 cell lines with IC50 values of 6.4 and 9.4 μM, respectively.

Two new 7,8-secolignans, neglectahenols E and F (1 and 2), together with four known 7,8-secolignans (3-6), were isolated from the fruits of Schisandra neglecta. The structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1-6 were tested for their anti-tobacco mosaic virus (anti-TMV) activities at the concentration of 20 mu M. Compounds 1 and 6 showed high anti-TMV activities with inhibition rates of 38.2% and 32.7%, respectively. These rates are higher than that of a positive control. Compounds 2-5 also showed modest anti-TMV activities with inhibition rates in the range of 22.8-28.7%. These rates are close to that of a positive control.

Three new prenylated chalcones, renifolins A-C (1-3), together with seven known ones (4-10), were isolated from whole Desmodium renifolium plants. All of their structures were determined by spectroscopic methods including 1D and 2D NMR. Compounds 1 and 2 are the first naturally occurring chalcones possessing a 4-methylfuran-2(5H)-one unit. All of the isolates were evaluated for cytotoxicity using five tumor cell lines. Compounds 3-8, and 10 exhibited moderate cytotoxicity against certain cell lines with IC50 values from 4.2 to 8.8 mu M. (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.

A new oxepinochromenone, rugosachromenone A (1), seven new flavonoids, rugosaflavonoids A-G (2-8), and 11 known compounds (9-19) were isolated from the flower buds of Rosa rugosa. Compound 1 is found from Nature for the first time. Compound 2 displayed cytotoxicity against NB4, SHSY5Y, and MCF7 cells with IC50 values of 2.2, 2.5, and 2.3 μM, respectively, and 3 was toxic to A549 and MCF7 cells with IC50 values of 1.2 and 2.8 μM, respectively.

Eight new C-4-alkylated deoxybenzoins (1-8), three new diphenylethylenes (9-11), and five known diphenylethylenes were isolated from Arundina graminifolia. The structures of 1-11 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 9-11 are the first naturally occurring diphenylethylenes possessing a hydroxyethyl unit. Compounds 1-11 were evaluated for cytotoxicity against five human tumor cell lines. Compounds 4, 5, and 9-11 showed significant cytotoxicity against five cancer cell lines, with IC50 values ranging from 1.8 to 8.7 μM.

Phytochemical investigations of the leaves of Garcinia paucinervis resulted in the isolation of three new xanthones 1–3 and five known analogues 4–8. Structural elucidations of 1–3 were performed by spectral methods such as 1D and 2D (HMQC, HMBC, and ROESY) NMR spectroscopy, in addition to high resolution mass spectrometry. Compounds 1–3 showed anti-TMV activities, with inhibition rates above 20%, especially for 1, which had a lower IC50 value of 21.4 µM.

Seven new unusual dibenzocyclooctadiene lignans, neglignans A-G (1-7), together with 16 known dibenzocyclooctadiene lignans, were isolated from the stems of Schisandra neglecta. Compounds 1 and 2 are the first dibenzocyclooctadiene lignans bearing a carboxyl group at C-4, and compounds 3 and 4 are the first 7,8-seco-dibenzocyclooctadiene lignans found from Nature. The new compounds (1-7) and several of the known compounds were evaluated for their anti-HIV activity and cytotoxicity. Compounds 2 and 6 showed anti-HIV-1 activities with therapeutic index values greater than 50, and compound 4 showed cytotoxicity against the NB4 and SHSY5Y cancer cell lines with IC50 values of 2.9 and 3.3 mu M, respectively.

Five new phenolic compounds, gramniphenols C-G (1-5), and eight known compounds (6-13) were isolated from the whole plant of Arundina gramnifolia. Compounds 1, 4, and 5 showed anti-tobacco mosaic virus activity, with IC(50) values of 20.8, 40.8, and 57.7 μM, respectively. Compounds 1-10 were also tested for their anti-HIV-1 activity; compounds 2, 3, and 6 displayed anti-HIV-1 activity with therapeutic index values above 100:1.

A new furan-2-carboxylic acid, 5-[3-(hydroxymethyl)-4,5-dimethoxyphenyl]-3-methylfuran-2-carboxylic acid(1),has been isolated from the bark of Cassia alata by using various chromatographic techniques. It displayed cytotoxicity against NB4, A549, SHSY5Y, PC3 and MCF7 cell lines with IC₅₀ values of 2.5, 1.2, 2.2, 3.6 and 1.9 μmol•L⁻¹, respectively.

Oryzaeins A-D (1-4), four new isocoumarin derivatives, along with five known ones (5-9) were isolated from solid cultures of an endophytic fungus Aspergillus oryzae. Their structures were elucidated by detailed spectroscopic analysis and by comparison with reported data of related derivatives. Among them, compounds 1 and 2 represent the first examples of isocoumarins possessing an unusual 2-oxopropyl group and a rare 3-hydroxypropyl group. Compounds 1 and 2 displayed moderate anti-tobacco mosaic virus activities with inhibition rates of 28.4% and 30.6%, respectively, at the concentration of 20 µM. The new compounds showed moderate inhibitory activities against several human tumor cell lines with IC50 values in the range of 2.8-8.8 µM. Supporting information available online at http://www.thieme-connect.de/products.

Two new dibenzocyclooctadiene lignans, rubrilignans A and B (1, 2), together with 17 known ones, were isolated from the fruits of Schisandra rubriflora. The structures of 1 and 2 were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were also evaluated for their anti-HIV-1 activities and showed weak anti-HIV-1 activity with EC(50) values of 2.26 and 1.82 μg/ml, and therapeutic index values of 35.5 and 18.6, respectively.

Rate constants of ozone with 39 aromatic compounds in aqueous solution were determined at 298 K. And optimized calculation was carried out at B3LYP/6-311G** level with DFT method. 10 molecular parameters obtained from calculations were selected as the descriptors to establish QSAR models for predicting the rate constants. These descriptors include structural, electronic and thermodynamic parameters. The optimum model was -logk' = 4.656 + 0.015CMA-1.684E (LUMO)-3.057qH(+), of which square regression coefficient R² = 0.791, standard deviation SD = 0.126. Stability of the model was checked by leave-one-out cross-validation and variation inflation factor. The QSAR model showed that the main contribution to degradation was the CMA parameter.

Two new flavones, siameflavones A and B (1 and 2), together with five known flavones (3-7) were isolated from the stem of Cassia siamea. Their structures were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. Compounds 1-5 were evaluated for their anti-tobacco mosaic virus (Anti-TMV) activity. The results showed that compounds 1-5 showed weak anti-TMV activity with inhibition rates in the range of 11.6-18.5%.