Anticomplement cycloartane triterpene glycosides from Beesia calthaefolia (Maxim.)

Investigation of the n-BuOH extract of the whole plant of Beesia calthaefolia led to the isolation of three new cycloartane triterpenoids (1–3) and two known compounds (4, 5). Their structures were elucidated by 1D and 2D NMR, HRESIMS and optical rotation spectral data. All of the isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 3 showed stronger inhibitory activity (IC₅₀ 148.0 μM) than the positive control (rosmarinic acid, IC₅₀ 181.8 μM), while other compounds (1, 2, 4 and 5) showed moderate activity. The chemical compound studied in this article was rosmarinic acid (PubChem CID: 5281792).     

Chemical constituents from Alnus mandshurica (Callier) Hand.-Mazz. and their chemotaxonomic significance

A new phenol compound, (9S)-9-hydroxy-9-[(2-hydroxyphenyl)methoxy]-nonanoic acid methyl ester (1) was isolated from the stem bark of Alnus mandshurica (Callier) Hand.-Mazz., along with eight known compounds (2–9). The structure of compound 1 was determined by spectral analyses, including HR-ESI-MS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. All the isolated compounds were reported for first time from A. mandshurica. Furthermore, compounds 3–9 were found in the family Betulaceae for the first time.     

Chemical constituents from the root bark of Dictamnus dasycarpus Turcz. (Rutaceae) and their chemotaxonomic significance

This work described the isolation and characterization of seven compounds from Dictamnus dasycarpus Turcz., including one new ester, (2R)-4-(2,2-dimethyl-5-oxotetrahydrofuran-3-yl)-2-hydroxypent-3-anoic acid ethyl ester (1); and six known glycosides (2–7). The structure of compound 1 was elucidated on the basis of extensive spectral analyses, including IR, HR-ESIMS, 1D and 2D NMR (NOESY, HMBC and HSQC). All these compounds were described here for the first time from the genus Dictamnus. Moreover, the results provide further information about the diversity of compounds in the genus Dictamnus.     

Chemical constituents from the stem bark of Acer tegmentosum

A new phenolic glycoside, 4-hydroxyphenylethyl-1-O-β-D-[6′-O-(4-hydroxybenzoyl)]-glucopyranoside (1) was isolated from the stem bark of Acer tegmentosum, along with seven known phenolic compounds (2–8). The structure of compound 1 was determined by spectral analyses, including HR-ESI-MS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. Compounds 3 and 4 were found in the family Aceraceae for the first time.     

Caffeoylquinic acid derivatives from the roots of Arctium lappa L. (burdock) and their structure–activity relationships (SARs) of free radical scavenging activities

Eight caffeoylquinic acid (CQA) derivatives have been identified from the roots of Arctium lappa L. (burdock), including three new derivatives (1–3) together with five known derivatives (4–8). Their chemical structures were determined by 1D and 2D NMR as well as HR-TOF-MS data. The free radical scavenging activities of each compound were determined experimentally and found to be significant, especially the tri-CQA (8) and di-CQAs (6–7). Besides, our data showed that the number of caffeoyl groups in the caffeoyl derivatives played a crucial role for these physiological functions.     

Chemical constituents from Sophora tonkinensis and their glucose transporter 4 translocation activities

Bioassay-guided phytochemical investigation of the EtOAc fraction (ST-EtOAc) from the roots of Sophora tonkinensis resulted in the isolation of a new compound 6aR,11aR-1-hydroxy-4-isoprenyl-maackiain (1), along with 12 known compounds (2–13). The structure of the new compound was established by 1D and 2D NMR, MS data and circular dichroism analysis. Polyprenylated flavonoids 6–9 and 11–13 increased GLUT-4 translocation by the range of 1.35–2.75 folds. Sophoranone (8) exerted the strongest activity with 2.75 folds GLUT-4 translocation enhancement at the concentration of 10 μM. This is the first report of the GLUT-4 translocation activity of the plant Sophora tonkinensis.     

Two new lignans with their biological activities in Portulaca oleracea L.

Two new lignans, identified as 6,7-dihydroxy-4-(4′’-hydroxy-3′’-methoxyphenyl)-2-naphthoic acid, named Oleralignan C (1), and 4-(3,4-dihydroxyphenyl)-6-hydroxy-7-methoxy-2-naphthoic acid, named Oleralignan D (2), were obtained from Portulaca oleracea L. The structures were determined by spectroscopic methods, including UHPLC-ESI-QTOFMS, ¹D and ²D NMR. Both Oleralignan C (1) and Oleralignan D (2) inhibited the inflammatory factors, IL-1β and TNF-α in RAW 264.7 cells induced by lipopolysaccharide (LPS). Both compounds also could clear 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radicals indicating their antioxidant potential.     

Acylated hydroxycinnamic acid glucosides from flowers of Telekia Speciosa

One new derivative of ferulic acid (1), two new caffeic acid derivatives (2 and 3) and three known derivatives of caffeic acid: 6-O-(E)-caffeoyl-glucopyranose (4), (E)-caffeic acid 4-O-β-glucopyranoside (5) and 5-caffeoylquinic acid (chlorogenic acid, 6) were isolated from a butanolic fraction of extract from Telekia speciosa flowers. Moreover, the flavonol glucoside–patulitrin (7) was identified in the analyzed extract. Structures of (E)-ferulic acid 4-O-β-(6-O-2-hydroxyisovaleryl)-glucopyranoside (1), (E)-caffeic acid 4-O-β-(6-O-2-hydroxyisovaleryl)-glucopyranoside (2) and (E)-caffeic acid 4-O-β-(6-O-3-hydroxy-2-methylpropanoyl)-glucopyranoside (3) were elucidated by 1D and 2D NMR, HRESIMS and other spectral analyses.     

A new depside and two new diphenyl ether compounds from the lichen Ramalina farinacea (L.) Ach

The chemical investigation of the Vietnamese lichen Ramalina farinacea (L.) Ach. led to the isolation and the structure elucidation of eight compounds (1–8), including one new depside, formulated as methyl homosekikate (1) and two new diphenyl ethers, 3-(2-carboxy-5-methoxy-3-propylphenoxy)-2-hydroxy-4-methoxy-6-propylbenzoic acid, namely ramalinic acid A (2), and 3-(2-carboxy-5-methoxy-3-propylphenoxy)-2-hydroxy-4-methoxy-6-pentylbenzoic acid, namely ramalinic acid B (3). Their chemical structures were unambiguously determined by analysis of 1D and 2D NMR and high resolution ESI mass spectroscopic data, as well as by comparison with literature data. We also proposed a possible biosynthetic route for the formation of the two new diphenyl ethers (2) and (3) via an enzymatically induced intramolecular Smiles rearrangement of the depsides sekikaic acid and homosekikaic acid, respectively.     

Isoflavones from the roots and stems of Nicotiana Tabacum and their anti-tobacco mosaic virus activities

Two new isoflavones, 7-hydroxy-6,3′,4′,5′-tetramethoxy-isoflavone (1) and 6-hydroxy-7,3′,4′,5′-tetramethoxy-isoflavone (2), together with seven known isoflavones were isolated from the roots and stems of Nicotiana tabacum. Their structures were determined by means of HRESIMS, extensive 1D and 2D NMR spectroscopic studies and chemical evidences. The anti-tobacco mosaic virus (anti-TMV) activities of the isoflavones were also evaluated. The results reveal that compound 9 shows high anti-TMV activity, compound 2 shows moderate anti-TMV activity, and compounds 1, 3–8 show weak anti-TMV activities.     

Simplex centroid mixture design,DI-ESI-MS,and chemometric analysis-guided isolation of parinarioidin C from bark of Brosimum parinarioides (Moraceae)

Brosimum parinarioides, a plant species native to the Amazonian region, is used in folk medicine for the treatment of several diseases. However, knowledge regarding its phytochemical content is scarce. In order to investigate the phytochemical composition of B. parinarioides, an integrative approach based on simplex-centroid design, direct infusion electrospray ionization mass spectrometry (DI-ESI-MS), and chemometric analysis was adopted. According to simplex-centroid design, dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol-based (EtOH) extracts were prepared and analyzed using DI-ESI-MS, and their chemical profile was submitted to principal component analysis (PCA) and hierarchical cluster analysis (HCA). The AcOEt extract from the bark was obtained on a large scale and subjected to chromatographic separation. The multivariate analysis indicated the formation of three groups and highlighted isoliquiritigenin (1), licoagrochalcone A (2), caffeic acid glucoside (3), epicatechin-glycoside (4), caffeic acid (5), and one unknown compound, as being responsible for the segregation of these groups. Thus, the new compound was isolated and characterized using 1D and 2D nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry (HR-MS) as parinarioidin C (10). In addition, parinarioidin A (6), parinarioidin B (7), 3-O-caffeoylquinic acid (8), and kanzonol C (9) were tentatively identified based on manual interpretation of MS/MS spectra. Overall, the integrative approach proposed in the study provided a simple and effective model to dereplicate known compounds and guide the isolation of a new compound from a native amazon species, thus improving the knowledge regarding the phytochemical content of B. parinarioides.     

Isolation,structure elucidation and in-vitro evaluation of new trisubstituted Tetrahydrofuran Lignans from Rabdosia lophanthoides var. gerardiana as anti-inflammatory agents

Four new trisubstituted tetrahydrofuran lignans, named (−)-sesaminone-rutinoside (1), (+)-episesaminone-rutinoside (2) and rabdosiacosides B (3) and C (4) were isolated from the air-dried whole herbs of Rabdosia lophanthoides var. gerardiana together with two known compounds, (+)− 1-hydroxypinoresinol-1-β-d-glucoside (5) and rosmarinic acid (6). The structures of these new lignans were elucidated by a combination of mass spectrometry, 1D and 2D NMR experiments including distortionless enhancement by polarization transfer, ¹H–¹H correlation, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, and nuclear Overhauser effect spectroscopies. Both the cell viability and their anti-inflammatory effects of the lignans were further studied. Among them, no significant cytotoxic activity was exhibited. Compound 4 dramatically suppressed LPS-induced nitric oxide release and reduced the release of the pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent manner. Overall, our findings indicate that compound 4 was noteworthy in reducing LPS-induced inflammatory responses in RAW264.7 macrophages.     

A new chromane derivative from the stem bark of Scyphocephalium ochocoa

A new chromane, 5,8-dihydroxy-2-(10′-phenyldecyl)chroman-4-one (1) was isolated from the stem bark of Scyphocephalium ochocoa, along with three known compounds (2–4). The structure of compound 1 was determined with help of spectroscopic data including IR, UV, HREIMS, 1D and 2D NMR (COSY, HMQC and HMBC) experiments. Furthermore, the chemotaxonomic significance of these compounds along with other compounds previously isolated from Scyphocephalium ochocoa was discussed.     

Two new flavonols,including one flavan dimer,from the roots of Indigofera stachyodes

A new flavan dimer, 2α,3α-epoxyflavan-5,7,3′,4′-tetraol-(4β→8)-flavan-5′′,7′′,4′′′-triol (1), and a new flavonol, 3-O-(3-nitropropanoyl)-2,3-cis-5,7,3′,4′-tetrahydroxyflavan (2), together with a known compound, 2α,3α-epoxy-5,7,3′,4′-tetrahydroxyflavan-(4β→8)-epicatechin (3), were isolated from the roots of Indigofera stachyodes. Their structures were elucidated by spectroscopic techniques including MS, 1D NMR, and 2D NMR. Compounds 2 and 3 were evaluated to determine their protective effects against carbon tetrachloride (CCl₄)-induced hepatotoxicity in the human liver cell line HL-7702. The results showed that 2 and 3 could protect HL-7702 cells from injury induced by CCl₄, with cell survival rates of 122.0% and 72.5%, respectively.     

Protective effect of Echinops galalensis against CCl4-induced injury on the human hepatoma cell line (Huh7)

Phytochemical investigation of the flowering aerial parts of Echinops galalensis (Asteraceae) led to the isolation of a new taraxasteryl triterpene, 3β-acetoxy-taraxast-12, 20(30)-diene-11α-21α-diol (1), together with nine known metabolites, α-amyrin (2), β-sitosterol (3), erythrodiol (4), lup-20(29)-ene-1,3-diol (5), 1,5-dicaffeoylquinic acid (6), 3,5-dicaffeoylquinic acid (7), 3,4-dicaffeoylquinic acid (8), 4,5-dicaffeoylquinic acid (9) and apigenin-7-O-β-d-glucoside (10). The structure of the new compound was determined by comprehensive analyses of their 1D and 2D NMR, mass spectral (HR-EI) data and comparison with previously known analogs. The effect of the methanol extract of E. galalensis, its fractions as well as compounds (1–10) on human hepatoma cell line (Huh7) was evaluated according to aspartate aminotransferase (AST), alanine transaminase (ALT), superoxide dismutase (SOD) activities and malondialdehyde (MDA) level before and after exposure of the cells to carbon tetrachloride (CCl₄). It was found that pre-treatment of human hepatoma cell line (Huh7) with the tested samples (100 μg/ml) prior to CCl₄ challenge protected against cell injury. The protective effect of E. galalensis was suggested to be mediated, at least partly, by its antioxidant activity.     

Valproic acid induces three novel cytotoxic secondary metabolites in Diaporthe sp., an endophytic fungus from Datura inoxia Mill.

Addition of the valproic acid (histone deacetylases inhibitor) to a culture of an endophytic fungus Diaporthe sp. harbored from Datura inoxia significantly altered its secondary metabolic profile and resulted in the isolation of three novel compounds, identified as xylarolide A (1), diportharine A (2) and xylarolide B (3) along with one known compound xylarolide (4). The structures of all the compounds (1–4) were determined by detailed analysis of 1D and 2D NMR spectroscopic data. The relative configurations of compounds 1–3 were determined with the help of NOESY data and comparison of optical rotations with similar compounds with established stereochemistry. All the isolated compounds were screened for antibacterial, antioxidant and cytotoxic activities. Xylarolide A (1) and xylarolide (4) displayed significant growth inhibition of MIAPaCa-2 with an IC₅₀ of 20 and 32?µM respectively and against PC-3 with an IC₅₀ of 14 and 18?µM respectively. Moreover, compound 1 displayed significant DPPH scavenging activity with EC₅₀ of 10.3?µM using ascorbic acid as a positive control.     

Alkaloids from the leaves of Isatis indigotica fortune and their chemotaxonomic significance

From the leaves of Isatis indigotica Fortune, one new alkaloid, namely (2E)-N-(2-hydroxyphenyl)-2-(1-hydroxy-3-oxoindolin-2-ylidene) acetamide (1), together with four known ones, such as phaitanthrin D (2), methyl quindoline-11-carboxylate (3), cephalandole B (4) and 2,2-di (3-indolyl)-3-indolone (5) were isolated and identified. The structure of compound 1 was elucidated by means of spectroscopic analysis, including HRESIMS together with 1D and 2D NMR experiments. Compounds 1, 2 and 5 were obtained from this genus for the first time. Chemotaxonomic significance of these compounds is described herein.     

Koninginins L and M,two polyketides from Trichoderma koningii 8662

Two new fungal metabolites, named koninginins L (1) and M (2), together with three known koninginins A (3), E (4), and trichodermaketone C (5), were isolated from solid fermentation products of Trichoderma koningii 8662. Koninginins L (1) and M (2) were elucidated by extensive spectroscopic methods, including 1D and 2D NMR, HR-EI-MS experiments, and the absolute configuration of compound 1 was confirmed by single-crystal X-ray diffraction analysis using the anomalous scattering of Cu Kα radiation.     

Phenylpropanoid constituents from the seeds of Lithocarpus pachylepis

Five phenylpropanoids including one new compound balanophonin A (1), one new natural compound balanophonin B (2) were isolated from the seeds of Lithocarpus pachylepis for the first time. Their structures were elucidated by various spectroscopic techniques (UV, IR, MS, CD, 1D and 2D NMR). All compounds were evaluated for their anti-inflammatory activities on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7.     

Tanzawaic acid derivatives from a marine isolate of Penicillium sp. (SF-6013) with anti-inflammatory and PTP1B inhibitory activities

Chemical investigation of a marine-derived fungus Penicillium sp. SF-6013 resulted in the discovery of a new tanzawaic acid derivative, 2E,4Z-tanzawaic acid D (1), together with four known analogues, tanzawaic acids A (2) and D (3), a salt form of tanzawaic acid E (4), and tanzawaic acid B (5). Their structures were mainly determined by analysis of NMR and MS data, along with chemical methods. Preliminary screening for anti-inflammatory effects in lipopolysaccharide (LPS)-activated microglial BV-2 cells showed that compounds 1, 2, and 5 inhibited the production of nitric oxide (NO) with IC₅₀ values of 37.8, 7.1, and 42.5 μM, respectively. Compound 2 also inhibited NO production in LPS-stimulated RAW264.7 murine macrophages with an IC₅₀ value of 27.0 μM. Moreover, these inhibitory effects correlated with the suppressive effect of compound 2 on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-stimulated RAW264.7 and BV2 cells. In addition, compounds 2 and 5 significantly inhibited the activity of protein tyrosine phosphatase 1B (PTP1B) with the same IC₅₀ value (8.2 μM).