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Fargesin is an important bioactive furofuran lignan isolated from different plant species. Despite presenting potent biological activities, its stereochemical characterization has relied mostly on empirical correlations of optical rotation, an approach considered risky that commonly leads to misassignments and error propagation. Additionally, the enantiomeric purity of fargesin isolates used for biological assays has not been previously investigated. Herein, we report the enantioresolution of a scalemic mixture of fargesin isolated from Aristolochia warmingii along with the first unambiguous determination of the absolute configuration of each enantiomer by means of optical rotatory dispersion, as well as electronic and vibrational circular dichroism aided by quantum-chemical calculations., (© 2024 Wiley Periodicals LLC.)

Five new furofuran lignans and their derivatives, (-)-glaberide I 4-O-β-D-glucopyranoside (1a), (+)-glaberide I 4-O-β-D-glucopyranoside (1b), (+)-glaberide I 7'-ethoxy-4-O-β-D-glucopyranoside (2a), (-)-glaberide I 7'-ethoxy-4-O-β-D-glucopyranoside (2b), and (-)-isoeucommin A (3b), along with fifteen known analogs were isolated from the stems of Dendrobium 'Sonia'. These compounds were classified into ten pairs of enantiomers or diastereoisomers via chiral resolution, and their structures were determined based on extensive spectroscopic data. Their absolute configurations were determined by hydrolysis, comparison of experimental and calculated electronic circular dichroism (ECD) data, and single-crystal X-ray diffraction analysis. The isolates were evaluated for their ability to inhibit nitric oxide (NO) production in RAW264.7 cells. Among them, syringaresinol (5) exhibited prominent inhibition activity, with an IC 50 value of 28.4 ± 3.0 μmol·L -1 , and there was a slight difference between 5a, 5b and the racemic mixture 5., (Copyright © 2024 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

Anemone vitifolia is a small herb found in Asia that is used to treat a range of diseases in Chinese traditional medicine. GNPS-based molecular networking of an Anemone vitifolia specimen revealed the presence of a network containing numerous ions indicating the presence of lignans, several of which suggested that there might be previously undescribed compounds in the extract. Fractionation of the organic extract yielded five undescribed lignans, the vitifolignans, together with one known. The structures were identified based on extensive spectroscopic data analysis (NMR, HR-ESI-MS, and UV), coupling constant calculation and comparison with reported data. Their absolute configurations were determined by comparison of experimental ECD spectra with calculated spectra. Compounds 4/5 showed weak inhibition of LPS-induced NO production in mouse mononuclear macrophages., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Arctigenin (Ar) is a promising therapeutic candidate for postmenopausal osteoporosis (PMOP). This study explores its mechanism by examining its effects on adipogenesis and osteogenesis in ovariectomized (OVX) rats. In vitro, Ar effectively suppressed the adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) from OVX rats, reducing lipid droplet formation and downregulating proteins associated with lipid synthesis. In vivo, Ar treatment significantly reduced bone loss, inhibited adipocyte development, improved lipid metabolism, and promoted bone formation in OVX rats. Mechanistically, Ar inhibited the phosphorylation of Mitogen-Activated Protein Kinase 1 (MEK1), downregulated Peroxisome Proliferator-Activated Receptor gamma (PPARγ), promoted the accumulation of β-catenin in the nucleus, and prevented the direct binding of PPARγ to β-catenin in BMSCs. This regulation of the PPARγ/Wnt signaling axis underlies its dual role in inhibiting adipogenesis and promoting osteogenesis. Notably, co-treatment with rosiglitazone (RGZ) reversed the effects of Ar on adipogenesis and osteogenesis without affecting MEK1 inhibition. These findings offer valuable insights into arctigenin's potential as a therapeutic strategy for PMOP by modulating MEK1 signaling and regulating the PPARγ/Wnt axis., (© 2024 John Wiley & Sons Ltd.)

Arctium lappa (Burdock) root is used in various culinary applications especially in Asian Cuisine. Arctigenin (ARC) is a polyphenolic compound abundant in the roots of the burdock plant from which it derives its name. The emergence of bacterial resistance is a growing global worry, specifically due to the declining availability of new antibiotics. Screening for the antibacterial candidates among the safe natural products is a promising approach. The present study was aimed to assess the antibacterial activity of ARC against Pseudomonas aeruginosa exploring its effect on the bacterial cell membrane. Furthermore, the anti-virulence activities and anti-quorum sensing (QS) activities of ARC were in vitro, in vivo and in silico assessed against P. aeruginosa . The current results showed the ARC antibacterial activity was owed to its disruption effect of the cell membrane. ARC at sub-MIC significantly decreased the formation of biofilm, motility, production of extracellular enzymes and in vivo protected mice against P. aeruginosa . These anti-virulence activities of ARC are owed to its interference with bacterial QS and its expression. Furthermore, ARC showed mild effect on mammalian erythrocytes, low probability to induce resistance and synergistically combined with antibiotics. In summary, the promising anti-virulence properties of ARC indicate its potential as an effective supplement to conventional antibiotics for treating severe P. aeruginosa infections.

Acne caused by inflammation of hair follicles and sebaceous glands is a common chronic skin disease. Arctigenin (ATG) is an extract of Arctium lappa L., which has significant anti-inflammatory effects. However, the effect and mechanism of ATG in cutaneous inflammation mediated by Cutibacterium acnes (C. acnes) has not been fully evaluated. The purpose of this study was to explore the effect and potential mechanism of ATG in the treatment of acne through network pharmacology and experimental confirmation. An acne model was established by injected live C. acnes into living mice and treated with ATG. Our data showed that ATG effectively improved acne induced by live C. acnes, which was confirmed by determining ear swelling rate, estradiol concentration and hematoxylin and eosin (H&E) staining. In addition, ATG inhibited the NLRP3 inflammasome signaling pathway in mice ear tissues and reduced the secretion of pro-inflammatory cytokines IL-1β to relieve inflammation. The results of network pharmacology and molecular docking confirmed that ATG can regulate 17β-Estradiol (E2) levels through targeted to CYP19A1, and finally inhibited skin inflammation. Taken together, our results confirmed that ATG regulated E2 secretion by targeting CYP19A1, thereby inhibiting the NLRP3 inflammasome signaling pathway and improving inflammation levels in acne mice. This study provides a basis for the feasibility of ATG in treating acne in clinical practice., (© 2024 John Wiley & Sons Ltd.)

Eucommiae Cortex (EC) is frequently used alone or in combination with other active ingredients to treat a range of illnesses. An efficient technical instrument for changing cheap or plentiful organic chemicals into rare or costly counterparts is biotransformation. It combines EC with biotransformation techniques with the aim of producing some novel active ingredients, using different strains of bacteria that were introduced to biotransform EC in an aseptic environment. The high-quality strains were screened for identification after the fermentation broth was found using HPLC, and the primary unidentified chemicals were separated and purified in order to be structurally identified. Strain 1 was identified as Aspergillus niger and strain 2 as Actinomucor elegans ; the main transformation product A was identified as pinoresinol (Pin) and B as dehydrodiconiferyl alcohol (DA). The biotransformation of EC utilizing Aspergillus niger and Actinomucor elegans is reported for the first time in this study's conclusion, resulting in the production of Pin and DA.

Arctigenin belongs to a major bioactive component of Fructus arctii and has been found with cardioprotective effects on rats with ischemia‒reperfusion (I/R) injury. The application of arctigenin is limited due to poor water solubility and low bioavailability. Hydrogel drug delivery systems can improve the efficacy and safety of drugs, increase drug utilization, and reduce side effects. We hypothesized that hydrogels containing arctigenin would facilitate the effect of arctigenin and alleviate I/R injury in the rat heart. Presently, adult Sprague-Dawley (SD) rats were subjected to 1 h of I/R injury, then hydrogels comprising arctigenin were implanted into the myocardium of rats. Triphenyl tetrazolium chloride staining, hematoxylin-eosin staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining and Western blot were performed for evaluating the infarct size, histopathological, and vital protein alterations of hearts. It was discovered that the hydrogel combined with arctigenin abated apoptosis and reduced infarct size. In addition, the results of echocardiography and Masson staining suggested that the hydrogel with arctigenin improved cardiac function, restrained myocardial fibrosis, and activated AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1). Collectively, the injectable hydrogel delivery system enhances the effect of arctigenin, which may play a protective role in I/R injury by activating AMPK and SIRT1., (© 2024 International Union of Biochemistry and Molecular Biology, Inc.)

Arctigenin (ARG) has potent antifatigue activity, but its clinical application has been restricted for its poor water solubility. In this study, seven ARG derivatives containing different amino acids coupled via an ethoxy linker were synthesized, and tested for their solubility, as well as activities to improve exercise performance in mice. All of the derivatives showed improved solubility compared to that of ARG. Derivative Z-A-6 exhibited the highest activity, showing that the mice ran a 4.88-fold greater distance in the running wheel test and swam a 2.86-fold greater time in the swimming test than those in the blank control group. Z-A-6 treatment increased the plasma superoxide dismutase and catalase concentrations as well as reduced lactic acid and blood urea nitrogen accumulation during exercise. Z-A-6 treatment enhanced the phosphorylation of adenosine monophosphate-activated protein kinase, and no acute toxicity was observed. The results will contribute to the development of potential antifatigue agents., (© The Author(s) 2023. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

Nine tetrahydrofuran lignans, including three undescribed spiro-lignans, were isolated from Isatis indigotica Fortune (Brassicaceae). Extensive spectroscopic analyses achieved the structure elucidation of these tetrahydrofuran lignans, and quantum chemical calculation combined with the MAE ΔΔδ parameter. Notably, isatispironeols A-B have a unique spiro[dienone-tetrahydrofuran] molecular core. These spiro[dienone-tetrahydrofuran] lignans showed comparable neuroprotective effects as the positive control in the H 2 O 2 -induced SH-SY5Y cells model. In addition, (-)-(7R,8S,1'R,7'R,8'R)-isatispironeol A possessed more significant AChE inhibitory activity, further interact sites were also predicted by the in silico assay., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Dibenzylbutyrolactone lignans (DBLs) are a class of natural products with a wide variety of biological activities. Due to their potential for the development of human therapeutic agents, DBLs have been subjected to various SAR studies in order to optimise activity. Previous reports have mainly considered changes on the aromatic rings and at the benzylic carbons of the compounds, whilst the effects of substituents in the lactone, at the C-9' position, have been relatively unexplored. This position has an unexploited potential for the development of novel dibenzyl butyrolactone derivatives, with previous preliminary findings revealing C-9'-hydroxymethyl analogues inducing programmed cell cycle death. Using the core structure of the bioactive natural product arctigenin, C-9' derivatives were synthesised using various synthetic pathways and with prepared derivatives providing more potent anti-proliferative activity than the C-9'-hydroxymethyl lead compound.

Arctium lappa L. is a prevalent medicinal herb and a health supplement that is commonly used in Asia. Over the last few decades, the bioactive component arctigenin has attracted the attention of researchers because of its anti-inflammatory, antioxidant, immunomodulatory, multiple sclerosis fighting, antitumor, and anti-leukemia properties. After summarising the research and literature on arctigenin, this study outlines the current status of research on pharmacological activity, total synthesis, and structural modification of arctigenin. The purpose of this study is to assist academics in obtaining a more comprehensive understanding of the research progress on arctigenin and to provide constructive suggestions for further investigation of this useful molecule.

Herein, the isolation of secondary metabolites from the aerial parts of Justicia aequilabris guided by HPLC-MS n and molecular networking analyses is reported. Twenty-two known compounds were dereplicated. Three new lignans (aequilabrines A-C ( 1 - 3 )) and three known compounds (lariciresinol-4'- O- β-glucose ( 4 ), roseoside ( 5 ), and allantoin ( 6 )) were obtained. The anti-inflammatory activity of compounds 1 - 3 was evaluated in vitro by inhibiting the nitric oxide production (NO) and pro-inflammatory activity on the cytokine IL-1β. Compounds 2 and 3 showed significant inhibitory activity against NO production, with IC 50 values of 9.1 and 7.3 μM, respectively. The maximum inhibition of IL-1β production was 23.5% ( 1 ), 27.3% ( 2 ), and 32.5% ( 3 ).

The Piper species are a recognized botanical source of a broad structural diversity of lignans and its derivatives. For the first time, Piper tectoniifolium Kunth is presented as a promising natural source of the bioactive (-)-grandisin. Phytochemical analyses of extracts from its leaves, branches and inflorescences showed the presence of the target compound in large amounts, with leaf extracts found to contain up to 52.78% in its composition. A new HPLC-DAD-UV method was developed and validated to be selective for the identification of (-)-grandisin being sensitive, linear, precise, exact, robust and with a recovery above 90%. The absolute configuration of the molecule was determined by X-ray diffraction. Despite the identification of several enantiomers in plant extracts, the major isolated substance was characterized to be the (-)-grandisin enantiomer. In vascular reactivity tests, it was shown that the grandisin purified from botanical extracts presented an endothelium-dependent vasorelaxant effect with an IC 50 of 9.8 ± 1.22 μM and around 80% relaxation at 30 μM. These results suggest that P. tectoniifolium has the potential to serve as a renewable source of grandisin on a large scale and the potential to serve as template for development of new drugs for vascular diseases with emphasis on disorders related to endothelial disfunction.

Albiziae Cortex (AC) is a well-known traditional Chinese medicine with sedative-hypnotic effects and neuroprotective ability. However, the bioactive components of AC responsible for the neuro-protective actitivity remain unknown. Here, we investigated the anti-neuroinflammatory effects of (-)-syringaresinol (SYR) extracted from AC in microglia cells and wild-type mice. As a result, (-)-SYR significantly reduced lipopolysaccharide (LPS)-induced production of interleukin - 6 (IL-6), tumor necrosis factor α (TNF-α), interleukin -1 beta (IL-1β), cycloxygenase-2 (COX-2), and nitric oxide (NO) in BV2 microglia cells. (-)-SYR also significantly reduced M1 marker CD40 expression and increased M2 marker CD206 expression. Moreover, we found that (-)-SYR inhibited LPS-induced NF-κB activation by suppressing the translocation of NF-κB p65 into the nucleus in a concentration-dependent manner. Meanwhile, estrogen receptor β (ERβ) was found to be implied in the anti-inflammatory activity of (-)-SYR in BV2 microglia. In vivo experiments revealed that administration of (-)-SYR in mice significantly reduced microglia/astrocytes activation and mRNA levels of proinflammatory mediators. Taken together, our data indicated that (-)-SYR exerted the anti-neuroinflammatory effects by inhibiting NF-κB activation and modulation of microglia polarization, and via interaction with ERβ. The anti-neuroinflammatory activity of (-)-SYR may provide a new therapeutic avenue for the treatment of brain diseases associated with inflammation., (Copyright © 2021 Elsevier B.V. All rights reserved.)

This paper presents a new high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method with a rapid analysis of 6 min to determine the concentration of galgravin in rat plasma so as to study its pharmacokinetic features and bioavailability in vivo. Schisandrin was selected as the internal standard (IS). After extracting the analyte from plasma samples with ethyl acetate, methanol-H 2 O (0.1% formic acid) (85 : 15, v / v ) was used as mobile phase to achieve chromatographic separation on a C18 reversed phase column. The MS detection was performed in positive ion mode using electrospray ionization (ESI) source. This method showed good linearity over the range of 1~500 ng/mL ( R 2 > 0.999), and the lower limit of quantitation (LLOQ) was 1.0 ng/mL. The intraday precision and interday precision were both within 8.5%, whereas the accuracies were in the range of -2.6%-6.0%. The average recoveries of galgravin in rat plasma were between 92.3% and 99.3%. Moreover, galgravin was stable throughout storage and processing with all RSDs below 12.1%. After the successful application of this optimized method, the oral bioavailability of galgravin was determined to be 8.5%. This study will be helpful to the future research and development of galgravin., Competing Interests: The authors declare that they have no conflict of interest., (Copyright © 2021 Lulu Zhao et al.)

Histone deacetylase 8 (HDAC8) has emerged as a promising drug target for cancer therapeutics development. HDAC8 has been reported to regulate cancer cell proliferation, invasion and promote metastasis through modulation of cell cycle associated proteins. Of late, phytocompounds have been demonstrated to exhibit anticancer and anti-HDAC8 activity. Here, we have shown the HDAC8 inhibitory potential of an active phytocompound from HC9 (herbal composition-9), a polyherbal anticancer formulation based on the traditional Ayurvedic drug, Stanya Shodhan Kashaya. HC9 was recently reported to exhibit anticancer activity against breast cancer cells through induction of cell cycle arrest, decrease in migration and invasion as well as regulation of inflammation and chromatin modulators. In silico studies such as molecular docking, molecular dynamics (MD) simulation and binding free energy analyses showed greater binding energy values and interaction stability of MA with HDAC8 compared to other phytocompounds of HC9. Interestingly, in vitro validation confirmed the anti-HDAC8 activity of MA. Further, in vitro studies showed that MA significantly decreased the viability of breast and prostate cancer cell lines, thereby confirming its anticancer potential., (Crown Copyright © 2021. Published by Elsevier B.V. All rights reserved.)

Arctigenin (ARG), a natural lignans compound isolated from Arctium lappa L. In this study, the anti-tumor effect of ARG on prostate cancer cell PC-3M and the mechanism of apoptosis and autophagy induced by phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway were discussed, and further confirmed by the joint treatment of ARG and PI3K inhibitor LY294002. Here, the effect of ARG on cell viability was evaluated in PC-3M cells by Cell Counting Kit-8 reagent (CCK-8) assay. After the treatment of ARG, colony formation assay was used to detect the anti-proliferation effect. Annexin V-fluoresceine isothiocyanate/propidium iodide (FITC/PI) kit and 4',6-diamidino-2-phenylindole (DAPI) staining were used to detect the apoptosis level, and cell cycle changes were analyzed by flow cytometry. The expression of autophagy was detected by acridine orange staining. In addition, the expression levels of apoptosis and autophagy-related proteins were analyzed by Western blot. The result showed that different concentrations of ARG inhibited the proliferation of PC-3M cells. DAPI staining and flow cytometry showed that ARG induced PC-3M cell apoptosis and arrested cell in G0/G1 phase. Acridine orange staining showed that ARG induced autophagy in PC-3M cells. Western blot experiments showed that ARG inhibited the expression of Bcl-2, promoted the expression of Bax and cleaved caspase-3. At the same time, the expression of autophagy-related proteins LC3B-II and Beclin-1 increased after ARG treatment, but P62 decreased. In addition, further studies have shown that treatment with LY294002 enhanced the effects of ARG on the expression of proteins associated with apoptosis and autophagy, indicating that ARG may induce apoptosis and autophagy through PI3K/Akt/mTOR pathway.

Laccases are multi-copper oxidases that catalyze the oxidation of various electron-rich substrates with concomitant reduction of molecular oxygen to water. The multi-copper oxidase/laccase CueO of Escherichia coli is responsible for the oxidation of Cu + to the less harmful Cu 2+ in the periplasm. CueO has a relatively broad substrate spectrum as laccase, and its activity is enhanced by copper excess. The aim of this study was to trigger CueO activity in vivo for the use in biocatalysis. The addition of 5 mM CuSO 4 was proven effective in triggering CueO activity at need with minor toxic effects on E. coli cells. Cu-treated E. coli cells were able to convert several phenolic compounds to the corresponding dimers. Finally, the endogenous CueO activity was applied to a four-step cascade, in which coniferyl alcohol was converted to the valuable plant lignan (-)-matairesinol., (© 2020 The Authors. ChemBioChem published by Wiley-VCH GmbH.)

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined., Competing Interests: The authors declare no conflict of interest.

Sesamum spp. (sesame) are known to accumulate a variety of lignans in a lineage-specific manner. In cultivated sesame (Sesamum indicum), (+)-sesamin, (+)-sesamolin and (+)-sesaminol triglucoside are the three major lignans found richly in the seeds. A recent study demonstrated that SiCYP92B14 is a pivotal enzyme that allocates the substrate (+)-sesamin to two products, (+)-sesamolin and (+)-sesaminol, through multiple reaction schemes including oxidative rearrangement of α-oxy-substituted aryl groups (ORA). In contrast, it remains unclear whether (+)-sesamin in wild sesame undergoes oxidation reactions as in S. indicum and how, if at all, the ratio of the co-products is tailored at the molecular level. Here, we functionally characterised SrCYP92B14 as a SiCYP92B14 orthologue from a wild sesame, Sesamum radiatum, in which we revealed accumulation of the (+)-sesaminol derivatives (+)-sesangolin and its novel structural isomer (+)-7´-episesantalin. Intriguingly, SrCYP92B14 predominantly produced (+)-sesaminol either through ORA or direct oxidation on the aromatic ring, while a relatively low but detectable level of (+)-sesamolin was produced. Amino acid substitution analysis suggested that residues in the putative distal helix and the neighbouring heme propionate of CYP92B14 affect the ratios of its co-products. These data collectively show that the bimodal oxidation mechanism of (+)-sesamin might be widespread across Sesamum spp., and that CYP92B14 is likely to be a key enzyme in shaping the ratio of (+)-sesaminol- and (+)-sesamolin-derived lignans from the biochemical and evolutionary perspectives., (© 2020 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)

Herein we report the preparation of 3,4-dibenzylfurans and some oxidized derivatives with lignan backbone. The compounds were prepared using the Friedel-Crafts reaction with BF 3 etherate as catalyst, demethylation with iodocyclohexane, acetylation and oxidation reactions. The antimicrobial activity was evaluated through their capacity to inhibit the growth of Gram positive and Gram negative bacteria, and of the yeast Candida albicans. Among ten products assayed four furans displayed a good antimicrobial activity against Staphylococcus aureus, S. epidermidis and C. albicans; on the contrary, none of the compounds were active against Pseudomonas aeruginosa. One of them inhibited the growth of S. aureus, S. epidermidis (biofilm producer strain) and C. albicans at 16 μg/mL, showing a bactericidal activity already after one hour of treatment. In summary, the results suggest a possible use of these derivatives for general disinfection practices or antimicrobial agents in cosmesis skin-care., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Furolignan-type natural products, possessing important biological properties, have been synthesized from a commercially available furan. The elaborated synthetic strategy is based on an innovative Friedel-Crafts reaction starting from an alcohol or a carboxylic acid and triflic anhydride as promoter. Through this synthetic strategy, furolignans having two different aryl groups have been obtained. The products have been evaluated for their antimicrobial properties on Gram positive and Gram negative bacteria, in order to compare their biological activities with those of natural analogues.

Tumors adapt to hypoxia by regulating angiogenesis, metastatic potential, and metabolism. These adaptations mediated by hypoxia-inducible factor 1 (HIF-1) make tumors more aggressive and resistant to chemotherapy and radiation. Therefore, HIF-1 is a validated therapeutic target for cancer. In order to develop new HIF-1 inhibitors for cancer chemotherapy by harnessing the potential of the natural product manassantin A, we synthesized and evaluated manassantin A analogues with modifications in the tetrahydrofuran core region of manassantin A. Our structure-activity relationship study indicated that the α,α'- trans -configuration of the central ring of manassantin A is critical to HIF-1 inhibition. We also demonstrated that a combination of manassantin A with an epidermal growth factor receptor inhibitor shows cooperative antitumor activity (∼80% inhibition for combination vs ∼30% inhibition for monotherapy). Our findings will provide important frameworks for the future therapeutic development of manassantin A-derived chemotherapeutic agents.

One of the arctigenin stereoisomers, (8R,8'R)-trans-form 1, showed stereospecific cytotoxicity against insect cells, Sf9 and NIAS-AeAl-2 cells. By the comparison with other stereoisomers, the most importance of the 8'R stereochemistry for the higher activities was clarified. On the other hand, the wider range of activity level among stereoisomers against cancer cells, HL-60, was not observed. The structure-activity relationship research using derivatives bearing (8R,8'R)-trans-form was performed to show the same level of activities of 3-iodo, 4-iodo, and 3,4-methylenedioxy derivatives 28, 29, and 36 as (8R,8'R)-trans-arctigenin 1. In the examination of thiono derivatives, 4-iodo thiono and 3,4-methylenedioxy thiono derivatives 66, 67 showed similar level of activities to that of (8R,8'R)-trans-arctigenin 1. The expression of ribosomal 28S rRNA gene of Sf9 cells was increased by (8R,8'R)-trans-arctigenin 1, whereas a degradation of DNA was not observed., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Two western red cedar pinoresinol-lariciresinol reductase (PLR) homologues were studied to determine their enantioselective, substrate versatility, and kinetic properties. PLRs are downstream of dirigent protein engendered, coniferyl alcohol derived, stereoselective coupling to afford entry into the 8- and 8'-linked furofuran lignan, pinoresinol. Our investigations showed that each PLR homolog can enantiospecifically metabolize different furofuran lignans with modified aromatic ring substituents, but where phenolic groups at both C4/C4' are essential for catalysis. These results are consistent with quinone methide intermediate formation in the PLR active site. Site-directed mutagenesis and kinetic measurements provided additional insight into factors affecting enantioselectivity and kinetic properties. From these data, PLRs can be envisaged to allow for the biotechnological potential of generation of various lignan skeleta, that could be differentially "decorated" on their aromatic ring substituents, via the action of upstream dirigent proteins., (© 2020 Wiley Periodicals, Inc.)

A dibenzylbutane-type lignan ( 16 ), along with eight furofuran-type ( 1 - 8 ), five furan-type ( 9 - 13 ), two dibenzylbutane-type ( 14 and 15 ), two bibenztetrahydronaphthalene-type lignans ( 17 and 18 ), two neolignans ( 19 and 20 ), and six phenolic derivatives ( 21 - 26 ) were isolated from an MeOH extract of the stem bark of Albizia julibrissin Durazz. The chemical structures of the obtained compounds were elucidated by nuclear magnetic resonance (NMR) and mass spectrometry (MS) analyses. Of the evaluated compounds, 14 were isolated from A. julibrissin and the Fabaceae family for the first time. Anti-inflammatory effects of the isolated analogs were investigated in terms of the inhibition of the nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine RAW264.7 macrophage cells. Ten compounds ( 10 - 12 , 14 , and 17 - 22 ) displayed significant dose-dependent inhibitory effects against the NO production, with IC 50 values ranging from 5.4 to 19.2 µM. Moreover, eight compounds ( 1 - 4 , 9 , 13 , 15 , and 16 ) exhibited moderate inhibitory activities, with IC 50 values ranging from 21.0 to 62.5 µM., Competing Interests: The authors declare no competing financial interests.

Lignans are widely produced by various plant species; they are a class of natural products that share structural similarity. They usually contain a core scaffold that is formed by two or more phenylpropanoid units. Lignans possess diverse pharmacological properties, including their antiviral activities that have been reported in recent years. This review discusses the distribution of lignans in nature according to their structural classification, and it provides a comprehensive summary of their antiviral activities. Among them, two types of antiviral lignans-podophyllotoxin and bicyclol, which are used to treat venereal warts and chronic hepatitis B (CHB) in clinical, serve as examples of using lignans for antivirals-are discussed in some detail. Prospects of lignans in antiviral drug discovery are also discussed.

Isoxazole analogues derived from the neolignans veraguensin, grandisin, and machilin G were previously synthesized with different substitution patterns through the bioisosterism strategy. These compounds were tested on intracellular amastigotes of Leishmania (Leishmania) amazonensis; the derivatives proved to be active against intracellular amastigotes, with IC 50 values ranging from 0.4 to 25 μM. The most active analogues were 4', 14', 15', and 18', with IC 50 values of 0.9, 0.4, 0.7, and 1.4 μM, respectively, showing high selectivity indexes (SI = 277.0; 625.0; 178.5 and 357.1). Overall, the isoxazole analogues did not induce nitric oxide (NO) production by infected cells; there was no evidence that NO influences the antileishmanial mechanism of action, except for compound 4'. Trimethoxy groups as substituents seemed to be critical for antileishmanial activity. The SAR study demonstrated that the isoxazole compounds were more active than 1,2,3-triazole compounds with the same substitution pattterns, demonstrating the importance of the bioisosterism strategy in drug design., (© 2019 John Wiley & Sons Ltd.)

Objective: This work describes the isolation of anti-Leishmania amazonensis metabolites from Saururus cernuus (Saururaceae). Additionally, ultrastructural changes in promastigotes were evidenced by electron microscopy., Methods: The MeOH extract from the leaves of S. cernuus was subjected to bioactivity-guided fractionation. Anti-L. amazonensis activity of purified compounds was performed in vitro against promastigote and amastigote forms., Key Findings: Bioactivity-guided fractionation of the MeOH extract from the leaves of S. cernuus afforded two related tetrahydrofuran dineolignans: threo,threo-manassantin A (1) and threo,erythro-manassantin A (2). Compounds 1 and 2 displayed activity against promastigotes (EC 50 of 35.4 ± 7.7 and 17.6 ± 4.2 μm, respectively) and amastigotes (EC 50 of 20.4 ± 1.9 and 16.0 ± 1.1 μm, respectively), superior to that determined for the positive control miltefosine (EC 50 of 28.7 ± 3.5 μm). Reduced cytotoxicity for host cells was observed for both compounds. Additionally, ultrastructural changes in promastigotes leading to an alteration of structural morphology were observed, as evidenced by electron microscopy. Furthermore, these compounds altered the morphology and physiology of the plasmatic membrane of L. amazonensis., Conclusions: The obtained results indicated that dineolignans 1 and 2 could be considered as a scaffold for the design of novel and selective drug candidates for the treatment of leishmaniasis., (© 2019 Royal Pharmaceutical Society.)

Nasopharyngeal carcinoma (NPC) is a head and neck epithelial malignancy with high prevalence and represents a significant disease burden. Eudesmin is a natural lignin that has been reported to exhibit antitumor effect on lung cancer. However, the effect of eudesmin on NPC has not been investigated. The aim of the present study was to evaluate the role of eudesmin in NPC and to explore the underlying mechanism. The NPC cell lines CNE-1 and HONE-1 were treated with eudesmin for 48 h. Cell viability was measured using MTT assay. Cell apoptosis was detected using flow cytometry. The expression levels of enhancer of zeste homolog 2 (EZH2), Akt, and p-Akt were measured using Western blot analysis. We found that eudesmin inhibited cell viability and induced cell apoptosis of NPC cell lines in a dose-dependent manner. Eudesmin suppressed the expression of EZH2 and blocked the activation of Akt signaling pathway. Inhibition of Akt signaling pathway caused significant decrease in EZH2 expression. Moreover, knockdown of EZH2 attenuated the effects of Akt overexpression on cell viability and apoptosis in NPC cells. In conclusion, eudesmin exhibited antitumor activity via downregulating EZH2 expression through the inhibition of Akt signaling pathway. Eudesmin could be developed as a new pharmacologic approach for NPC treatment., (Copyright © 2019. Published by Elsevier B.V.)

Objective: To explore whether Arctigenin-Valine ester (ARG-V) can treat myelosuppression caused by chemotherapy., Methods: The number of peripheral blood cells of the mice was measured by an automatic blood analyzer, and the hematopoietic progenitor colonies CFU-GM, CFU-E, BFU-E, and CFU-Meg were cultured in vitro. Hematopoietic progenitor colonies and BMNCs were counted under an inverted microscope. The expressions of cytokines GM-CSF, EPO and TPO were detected by ELISA. The cell cycle was measured by flow cytometry. The expressions of related proteins MEK and p-ERK were quantitated by western blots, and the thymus index and spleen index were quantitated., Results: After taking ARG-V, the peripheral blood cells of the mice gradually returned to normal, the number of nucleated cells in the bone marrow increased, the thymus index increased, the spleen index decreased, the number of hematopoietic progenitor cells increased, and the hematopoietic cytokines decreased. And ARG-V promoted the transformation of myelosuppression cells from G0/G1 to S and from S to G2/M. ARG-V could up-regulate the expression of MEK and p-ERK, and low dose ARG-V is not as effective in all aspects as high dose ARG-V., Conclusion: ARG-V can effectively alleviate the myelosuppression that caused by intraperitoneal injection of CTX in 100mg/kg, and ARG-V can promote the proliferation and differentiation of hematopoietic progenitor cells and improve immunity, and the effect of high-dose Arctigenin-Valine ester is more significant to some extent., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Furofuran lignans containing the 2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane skeleton, represent one of the major subclasses of the lignan family of natural products. Furofuran lignans feature a wide variety of structures due to different substituents at aryl groups and diverse configurations at furofuran ring. Moreover, they exhibit a wide range of significant biological activities, including antioxidant, anti-inflammatory, cytotoxic, and antimicrobial activities. This review summarizes source, phytochemistry, and biological activities of 137 natural furofuran lignans isolated from 53 species in 41 genera of 27 plant families for the last 20 years, which provides a comprehensive information for further research of these furofuran lignans as potential pharmaceutical agents.

Microenvironmental stress, which is naturally observed in solid tumors, has been implicated in anticancer drug resistance. This tumor-specific stress causes the degradation of topoisomerase IIα, rendering cells resistant to topoisomerase IIα-targeted anticancer agents. In addition, microenvironmental stress can induce the overexpression of 78kDa glucose regulated protein (GRP78), which can subsequently block the activation of apoptosis induced by treatment with anticancer agents. Therefore, inhibition of topoisomerase IIα degradation and reduction in GRP78 expression may be effective strategies for inhibiting anticancer drug resistance. In this study, we investigated the active compound arctigenin, which inhibited microenvironmental stress-induced etoposide resistance in HT-29 cells. Arctigenin was also highly toxic to etoposide-resistant HT-29 cells, with an IC 50 value of 10 μM for colony formation. We further showed that arctigenin inhibited the degradation of topoisomerase IIα and reduced the expression of GRP78. Thus, these results suggest that arctigenin is a novel therapeutic agent that inhibits resistance to etoposide associated with microenvironmental stress conditions.

Six new neolignans, sinensiols B-G (1-6), together with three known analogues (7-9) were isolated from the whole plant of Selaginella sinensis. Their planar structures were established by comprehensive spectroscopic analyses including 1D, 2D NMR, IR and HRESIMS data. The absolute configurations of new compounds were elucidated by comparing their experimental CD spectra with known ones and using the reversed helicity rule for the 1 L b band ECD of dihydrobenzofuran neolignans. Sinensiols A-D (7, 1-3) belong to sesquilignan with a dimer of dihydrobenzo[b]furan moiety. The potential precursors of sinensiols A, B, D were also reported in this paper. In addition, all new compounds were screened for their cytotoxicity against A549 and HepG2 human cancer cell lines, and they didn't show inhibition on the growth of cancer cells., (Copyright © 2019. Published by Elsevier B.V.)

Using bioisosterism as a medicinal chemistry tool, 16 3,5-diaryl-isoxazole analogues of the tetrahydrofuran neolignans veraguensin, grandisin and machilin G were synthesized via 1,3-dipolar cycloaddition reactions, with yields from 43% to 90%. Antitrypanosomatid activities were evaluated against Trypanosoma cruzi, Leishmania (L.) amazonensis and Leishmania (V.) braziliensis. All compounds were selective for the Leishmania genus and inactive against T. cruzi. Isoxazole analogues showed a standard activity on both promastigotes of L. amazonensis and L. braziliensis. The most active compounds were 15, 16 and 19 with IC 50 values of 2.0, 3.3 and 9.5 μM against L. amazonensis and IC 50 values of 1.2, 2.1 and 6.4 μM on L. braziliensis, respectively. All compounds were noncytotoxic, showing lower cytotoxicity (>250 μM) than pentamidine (78.9 μM). Regarding the structure-activity relationship (SAR), the methylenedioxy group was essential to antileishmanial activity against promastigotes. Replacement of the tetrahydrofuran nucleus by an isoxazole core improved the antileishmanial activity., (© 2018 John Wiley & Sons A/S.)

Twenty-three resin samples have been obtained by tapping from individual Pinus pinaster adult trees grown in Corsica and submitted to acido-basic partition. Identification and quantitative determination of resin acids has been carried out using 13 C-NMR spectroscopy following a method developed by our group. The main components were dehydroabietic acid (up to 37.6 %), levopimaric acid (up to 35.5 %) and abietic acid (up to 24.7 %). A lignan, pinoresinol, has been identified in some samples. Within the 23 compositions, submitted to k-means analysis and Principal Component Analysis, two clusters have been perfectly differentiated, whose compositions were dominated by dehydroabietic acid (Group I, M=23.5 %, SD=6.3) and levopimaric acid (Group II, M=21.2 %; SD=6.2), respectively. Both compositions have been observed in the three locations of harvest., (© 2019 Wiley-VHCA AG, Zurich, Switzerland.)

Dibenzyl butyrolactone lignans are well known for their excellent biological properties, particularly for their notable anti-proliferative activities. Herein we report a novel, efficient, convergent synthesis of dibenzyl butyrolactone lignans utilizing the acyl-Claisen rearrangement to stereoselectively prepare a key intermediate. The reported synthetic route enables the modification of these lignans to give rise to 5-hydroxymethyl derivatives of these lignans. The biological activities of these analogues were assessed, with derivatives showing an excellent cytotoxic profile which resulted in programmed cell death of Jurkat T-leukemia cells with less than 2% of the incubated cells entering a necrotic cell death pathway., Competing Interests: The authors declare no conflict of interest.

Four new series of arctigenin derivatives were designed, synthesised, and evaluated for their anti-Toxoplasma gondii activity in vitro and in vivo. Among the synthesised compounds, 4-(3,4-dimethoxybenzyl)-3-(4-((1-(2-fluorobenzyl)-1H- 1,2,3-triazol-4-yl)methoxy)-3-methoxybenzyl)dihydrofuran-2(3H)-one (D4) exhibited the most potent anti-T. gondii activity and low cytotoxicity (IC 50 in T. gondii: 17.1 μM; IC 50 in HeLa cells: ≥ 600.0 μM; Selectivity: 35.09), demonstrating better results than the lead compound arctigenin (IC 50 in T. gondii: 586.4 μM; IC 50 in HeLa cells: 572.7 μM; Selectivity: 0.98) and the clinically applied positive-control drug spiramycin (IC 50 in T. gondi: 262.2 μM; IC 50 in HeLa cells: 189.0 μM; Selectivity: 0.72) in vitro. Furthermore, 2-(4-((4-(3,4-dimethoxybenzyl)-2-oxotetrahydrofuran-3-yl)methyl)-2- methoxyphenoxy)N-phenylacetamide (E5) had better inhibitory effects on T. gondii in vivo than spiramycin did. Compound D4 and E5 not only significantly reduced the number of tachyzoites in the peritoneal cavity of mice, but also resulted in their partial malformation (P < 0.05) in vivo. The determination of liver and spleen index and biochemical parameters, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutathione (GSH) and malondialdehyde (MDA), were comprehensively evaluated for compound D4 and E5's anti-T. gondii activity and some damage to the liver. In addition, the results of a docking study of D4 into the T. gondii calcium-dependent protein kinase 1 (TgCDPK1) receptor protein-binding site revealed that its mode of action was possibly as a TgCDPK1 inhibitor. Overall, the results revealed that D4 and E5 are promising lead compounds for the further development and identification of arctigenin derivatives as anti-T. gondii agents., (Copyright © 2018. Published by Elsevier Masson SAS.)

We examined the anti-inflammatory effects of (+)-syringaresinol (SGRS), a lignan isolated from Rubia philippinensis, in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells using enzyme-based immuno assay, Western blotting, and RT-PCR analyses. Additionally, in vivo effects of SGRS in the acute inflammatory state were examined by using the carrageenan-induced hind paw edema assay in experimental mice. As a result, treatment with SGRS (25, 50, and 100 μM) inhibited protein expression of lipopolysaccharide-stimulated inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor kappa B (NF-κB) as well as production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and interleukin-6 (IL-6) induced by LPS. Moreover, SGRS also reduced LPS-induced mRNA expression levels of iNOS and COX-2, including NO, PGE2, TNF-α, IL-1β, and IL-6 cytokines in a dose-dependent fashion. Furthermore, carrageenan-induced paw edema assay validated the in vivo anti-edema effect of SGRS. Interestingly, SGRS (30 mg/kg) suppressed carrageenan-induced elevation of iNOS, COX-2, TNF-α, IL-1β, and IL-6 mRNA levels as well as COX-2 and NF-κB protein levels, suggesting SGRS may possess anti-inflammatory activities.

The compounds of N-Methylanhydrotetrahydroberberrubine A, dictamnine and eudesmin were the primary bioactive components in the roots of Zanthoxylum armatum DC (Z. armatum). To clarify the pharmacokinetics and distribution of these three compounds, an ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was employed to determine the contents of these three compounds in rat plasma and seven tissues. The separation was achieved on a Kinetex XB-C18 100A column (2.1 × 50 mm, 2.6 μm, Phenomenex). The optimized mobile phase system was set with 0.1‰ formic acid aqueous solution (A) and acetonitrile (containing 0.1‰ formic acid) (B) with a programmed elution of 0.00 to 0.50 min, 2% B; 0.51-4.00 min, 30%-60% B; and 4.01-5.00 min, 2% B. All analytes were measured with optimized multiple reaction monitoring (MRM) in the positive ion ESI mode. Berberine hydrochloride was selected as the internal standard (IS). The MS/MS transitions of N-Methylanhydrotetrahydroberberrubine A, dictamnine, eudesmin and IS were 339.9135.1, 200.1 → 129.1, 387.4 → 369.0 and 337.1 → 321.1, respectively. The lower limits quantification (LLOQ) of the three analytes was 0.5-20 ng/ml. The linear ranges were 0.5-400 ng/ml for N-Methylanhydrotetrahydroberberrubine A and dictamnine and 20-4000 ng/ml for eudesmin. The present analysis showed that the two alkaloids were quickly absorbed, with T max in 0.167-0.292 h, and eudesmin was absorbed in 2.5 h. Moreover, all compounds were found at high concentrations in the gastrointestinal track. These results are helpful for further investigation of the clinical application of Z. armatum., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two new sucrose derivatives, namely, belamcanosides A ( 1 ) and B ( 2 ), together with five other known compounds ( 3 - 7 ), were isolated from the seeds of Belamcanda chinensis (L.) DC. Their structures were identified based on spectroscopic data. Especially, the absolute configurations of fructose and glucose residues in 1 and 2 were assigned by acid hydrolysis, followed by derivatization and gas chromatography (GC) analysis. Among the known compounds, (-)-hopeaphenol ( 3 ), (+)-syringaresinol ( 4 ), and quercetin ( 5 ), were isolated from B. chinensis for the first time. In addition, biological evaluation of 1 and 2 against cholesterol synthesis and metabolism at the gene level was carried out. The results showed that compounds 1 and 2 could regulate the expression of cholesterol synthesis and metabolism-associated genes, including 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), squalene epoxidase (SQLE), low density lipoprotein receptor (LDLR), and sortilin (SORT1) genes in HepG2 cells., Competing Interests: The authors declare that there is no conflict of interest.

The present study aimed to determine the protective effects of arctigenin against myocardial infarction (MI), and its effects on oxidative stress and inflammation in rats. Left anterior coronary arteries of Sprague‑Dawley rats were ligated, in order to generate an acute MI (AMI) model. Arctigenin was administered to AMI rats at 0, 50, 100 or 200 µmol/kg. Western blotting and ELISAs were performed to analyze protein expression and enzyme activity. Arctigenin was demonstrated to effectively inhibit the levels of alanine transaminase, creatine kinase‑MB and lactate dehydrogenase, and to reduce infarct size in AMI rats. In addition, the activity levels of malondialdehyde, interleukin (IL)‑1β and IL‑6 were significantly suppressed, and the levels of glutathione peroxidase, catalase and superoxide dismutase were significantly increased by arctigenin treatment. Arctigenin treatment also suppressed the protein expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX‑2) and heme oxygenase 1 (HO‑1), and increased the protein expression levels of phosphorylated‑extracellular signal‑regulated kinase 1/2 (p‑ERK1/2) in AMI rats. Overall, the results of the present study suggest that arctigenin may inhibit MI, and exhibits antioxidative and anti‑inflammatory effects through regulation of the iNOS, COX‑2, ERK1/2 and HO‑1 pathways in a rat model of AMI.

Arctigenin (ARG) is a functional active component that has important physiological and pharmacological activities. The anti-tumour and anti-inflammatory activities of ARG show good potential for application and development, but this material has the defect of low water solubility. In this experiment, the valine derivative of ARG (ARG-V) was designed and synthesized to overcome this disadvantage. The ARG amino acid, EDCI and DMAP were raw materials in the addition reaction, with a molar ratio of 1:2:2:0.5. The yield of ARG-V was up to 80%. ARG-V has strong anti-tumour activity in vivo and in vitro. The inhibitory rate of ARG-V was 69.2%, with less damage to the immune organs and different degrees of increased serum cytotoxicity. Moreover, the pharmacokinetics of ARG following oral administration and ARG-V following oral administration in rats were also studied. The C max and AUC values of ARG-V showed significant differences compared to ARG. The relative bioavailabilities of three doses of ARG-V compared to ARG were 664.7%, 741.5% and 812.9%. These pharmacokinetic results may be useful for further studies of the bioactive mechanism of ARG and provide a theoretical basic for clinical use.

Arctigenin (ARG) is famous in its abundant pharmacological activity. However, many researches in it entered the bottleneck period because of its poor water solubility. The derivatives of ARG have been synthesised with five amino acids which have t-Butyloxy carbonyl (BOC) as a protective group. We examined the effects of removing BOC. The results showed that the amino acid derivatives without protective group have better water solubility and nitrite-clearing ability than ARG. Based on these results, ARG6' and ARG9' were selected at a dosage of 40 mg/kg to evaluate their antitumour activity. The percentage inhibition rate of ARG6' and ARG9' were 55.87 and 51.40, respectively, which was twice as much as ARG. Furthermore, they could increase liver and kidney indexes and produce less damage in these organs. In brief, this study provides a basis for new drug development.

A very short three-step approach to trans,trans,trans-2,5-diaryl-3,4-dimethyltetrahydrofuran lignans is reported. The carbon skeleton is assembled in a single step based on an unprecedented tandem reaction consisting of 1,2-addition of aryllithium reagents to α,β-unsaturated aldehydes, ruthenium-catalyzed redox isomerization of the resulting alkoxides to enolates and their dimerization triggered by single electron oxidation. The resulting 2,3-dialkyl-1,4-diketones form with moderate to good d/l-diastereoselectivity and are transformed to the target tetrahydrofuran lignans by reduction and diastereoselective cycloetherification.

Lignans are a large class of naturally occurring secondary metabolites which are widely spread within the plant kingdom. Their diverse structures and variety of biological activities have fascinated organic chemists. For synthesizing optically active lignans, we have developed the novel asymmetric dimerization of cinnamic acid derivatives, and applied it to the enantioselective syntheses of furofuran lignans (yangambin, sesamin, eudesmin, caruilignan A) and diarylbutane lignans (sauriols A and B). This review summarizes the methodology of our asymmetric dimerization of cinnamic acid derivatives, and efficient total syntheses of furofuran and diarylbutane lignans reported by our and other groups.

EtOAc extract from the leaves of Terminalia citrina collected in Bangladesh were separated, and seven previously undescribed α-keto tetrahydrofuran lignan glucosides (terminalosides Q to W) were isolated and characterized. NOESY analysis of 1 H NMR spectra and ECD spectroscopic data analysis revealed the absolute stereochemistry of the tetrahydrofuran ring of the isolated constituents as being a (7S,8R,8'S)- configuration in terminalosides Q to U and a (7R,8R,8'S)- configuration in terminalosides V and W. All of the isolated compounds were evaluated for their estrogenic and anti-estrogenic properties using two types of estrogen-responsive human breast cancer cell lines (MCF-7 and T47D). Terminaloside R, which has a dioxymethylene group in its aromatic ring, inhibited 90% of estradiol-enhanced cell proliferation in T47D and MCF-7 cells at concentrations of 0.01 μM and 0.1 μM, respectively. On the other hand, terminaloside T, the analogous compound which has two oxymethyl groups in place of dioxymethylene, suppressed 90% of cell proliferation selectively in T47D cells at a concentration of 0.01 μM. However, terminaloside W, the 7R-stereoisomer of terminaloside R, only showed moderate activity., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The present study was designed to improve storage stability and oral bioavailability of Ganneng dropping pills (GNDP) by transforming lignans of Herpetospermum caudigerum (HL) composed of herpetrione (HPE) and herpetin (HPN) into nanosuspension (HL-NS), the main active ingredient of GNDP, HL-NS was prepared by high pressure homogenization and lyophilized to transform into solid nanoparticles (HL nanoparticles), and then the formulated HL nanoparticles were perfused into matrix to obtain NS-GNDP by melting method. For a period of 3 months, the content uniformity, storage stability and pharmacokinetics test in vivo of NS-GNDP were evaluated and compared with regular GNDP at room temperature. The results demonstrated that uniformity of dosage units of NS-GNDP was acceptable according to the criteria of Chinese Pharmacopoeia 2015J. Physical stability of NS-GNDP was investigated systemically using photon correlation spectroscopy (PCS), zeta potential measurement, and scanning electron microscopy (SEM). There was a slight increase in particles and PI of HL-NS re-dispersed from NS-GNDP after storage for 3 months, compared with new formulated NS-GNDP, which indicated a good redispersibility of the NS-GNDP containing HL-NS after storage. Besides, chemical stability of NS-GNDP was studied and the results revealed that HPE and HPN degradation was less when compared with that of GNDP, providing more than 99% of drug residue after storage for 3 months. In the dissolution test in vitro, NS-GNDP remarkably exhibited an increased dissolution velocity compared with GNDP and no distinct dissolution difference existed within 3 months. The pharmacokinetic study showed that HPE and HPN in NS-GNDP exhibited a significant increase in AUC 0-t , C max and decrease in T max when compared with regular GNDP. These results indicated that NS-GNDP possessed superiority with improved storage stability and increased dissolution rate and oral bioavailability., (Copyright © 2018 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

(+)-Sesamin, (+)-sesamolin, and (+)-sesaminol glucosides are phenylpropanoid-derived specialized metabolites called lignans, and are rich in sesame (Sesamum indicum) seed. Despite their renowned anti-oxidative and health-promoting properties, the biosynthesis of (+)-sesamolin and (+)-sesaminol remained largely elusive. Here we show that (+)-sesamolin deficiency in sesame is genetically associated with the deletion of four C-terminal amino acids (Del4C) in a P450 enzyme CYP92B14 that constitutes a novel clade separate from sesamin synthase CYP81Q1. Recombinant CYP92B14 converts (+)-sesamin to (+)-sesamolin and, unexpectedly, (+)-sesaminol through an oxygenation scheme designated as oxidative rearrangement of α-oxy-substituted aryl groups (ORA). Intriguingly, CYP92B14 also generates (+)-sesaminol through direct oxygenation of the aromatic ring. The activity of CYP92B14 is enhanced when co-expressed with CYP81Q1, implying functional coordination of CYP81Q1 with CYP92B14. The discovery of CYP92B14 not only uncovers the last steps in sesame lignan biosynthesis but highlights the remarkable catalytic plasticity of P450s that contributes to metabolic diversity in nature.