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The genus Penicillium has provided us with the household antibiotic penicillin and the well-known lipid-lowering agent mevastatin. The strain Penicillium sp. SZ-1 was found to grow vigorously in an intact Pinus koraiensis seed, it is inferred that the strain may develop unique mechanisms associated with the biosynthesis of rare metabolites. Further fermentation of the strain on solid rice medium yielded thirteen undescribed compounds, including three andrastin-type meroterpenoids (1-3), two α-pyrone polyketides (4 and 5), and eight sesquicarane derivatives (6-13), along with seven known compounds (14-20). Their structures were determined by detailed analysis of the spectroscopic and spectrometric data (NMR and HRESIMS), in addition to comparisons of the experimental and calculated ECD data for absolute configurational assignments. The hemiacetal moiety in compounds 1 and 2 and the 3α-hydroxy group in compound 3 were rarely found in the andrastin-type meroterpenoid family. The sesquicaranes belong to a small group of sesquiterpenoid that are rarely reported. Bioassay study showed that compound 1 exhibited inhibitory effects against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922 with MIC values of 64 and 32 μg/mL, respectively. In addition, compounds 1 and 3 displayed weak DPPH radical scavenging activities. The andrastins and sesquicaranes in this study enriched the structural diversity of these classes of terpenoids. Of note, this study is the first report on the metabolites of a fungus isolated from P. koraiensis seed., 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.)

This work discusses the ongoing challenge of cancer, focusing on therapy issues such as chemotherapy resistance and adverse drug effects. It emphasizes the need for new anticancer agents with improved efficacy and fewer side effects, exploring natural products from plant sources. The Annonaceae family, specifically the Annona genus, is highlighted for its medicinal properties, including anti-inflammatory and anticancer effects. The study focuses on the isolation and elucidation of the substances present in Annona acutiflora leaves. The methodology involves chromatographic and spectroscopy techniques. The isolated compounds, (6S)-5'-oxohepten-1'E,3'E-dienyl)-5,6-dihydro-2H-pyran-2-one (1), (6R)-5'-oxohepten-1'Z,3'E-dienyl)-5,6-dihydro-2H-pyran-2-one (2) and (6R)-5'-oxohepten-1'Z,3'E-dienyl)-5,6-dihydro-2H-pyran-2-one (3) were investigated for cytotoxicity assays on cancer cell lines and normal cells. Results show promising cytotoxic activity, particularly with compound 3, demonstrating potential activity against oral cancer (43.18 μM), hepatocarcinoma (17.24 μM), melanoma (5.39 μM), and colon cancer (59.03 μM). The compound outperforms carboplatin in selectivity against oral cancer (S. I. 2.15) and melanoma (S. I. 17.22). The study concludes by suggesting the potential of these α-pyrones as effective and less toxic alternatives for cancer therapy., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Five cyclopenta[ d ]pyrano[4,3- b ]pyran-1,7(6 H )-dione 6/6/5-fused tricyclic ring system containing metabolites peniapyrones A-E ( 1 - 5 ), and four previously undescribed cyclopenta[4,5]furo[3,2- c ]pyran-1-one 6/5/5-fused tricyclic ring system containing compounds peniapyrones F-I ( 6 - 9 ), were isolated from the endophytic Penicillium brefeldianum F4a. Their structures, including absolute configurations, were determined through spectroscopic analysis and quantum chemical calculations. Peniapyrones D ( 4 ) and E ( 5 ) were a pair of diastereoisomers. Compounds 1 , 3 , and 5 - 9 showed cytotoxic activity against AsPC-1, CRL-2234, and MCF-7 cancer cell lines. Compounds 1 , 3 , 6 , 8 , and 9 inhibited the Kirsten rat sarcoma viral oncogene homologue (KRAS) mutant AsPC-1 cell line.

Two new meroterpenoids, aspergienynes O and P ( 1 and 2 ), one new natural compound, aspergienyne Q ( 3 ), and a new α-pyrone derivative named 3-(4-methoxy-2-oxo-2H-pyran-6-yl)butanoic acid ( 4 ) were isolated from the mangrove endophytic fungal strain Aspergillus sp. GXNU-Y85, along with five known compounds ( 5 - 9 ). The absolute configurations of those new isolates were confirmed through extensive analysis using spectroscopic data (HRESIMS, NMR, and ECD). The pharmacological study of the anti-proliferation activity indicated that isolates 5 and 9 displayed moderate inhibitory effects against HeLa and A549 cells, with the IC 50 values ranging from 16.6 to 45.4 μM.

Endophytic fungi live asymptomatically inside vegetal tissues, and such uncommon habitat contributes to their exceptional chemical diversity. Isolating natural products from endophytic fungi could fail due to silent biosynthetic gene clusters under ordinary in vitro culture conditions, and co-culturing has been assayed to trigger their metabolism. We carried out single and dual cultures with 13 endophyte strains isolated from Euphorbia umbellata leaves. Multivariate statistics applied to untargeted metabolomics compared the chemical profiles of all endophyte cultures. PCA analysis guided the selection of the Aspergillus pseudonomiae J1 - Porogramme brasiliensis J9 dual culture for its most significant chemical differentiation: Five compounds were putatively annotated in the J1-J9 culture according to UHPLC-HRMS data, kojic acid, haliclonol and its diastereoisomer, caffeic acid, and 2-(3,4-dihydroxyphenyl)acetaldehyde. Analysis by PLS-DA using VIP score showed that kojic acid displayed the most significative importance in discriminating single and dual J1-J9 cultures., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Two pairs of new enantiomeric hydroxyphenylacetic acid derivatives, (±)-corylophenols A and B ((±)-1 and (±)-2), a new α-pyrone analogue, corylopyrone A (3), and six andrastin-type meroterpenoids (4-9) were isolated and identified from the deep-sea cold-seep sediment-derived fungus Penicillium corylophilum CS-682. Their structures and stereo configurations were determined by detailed spectroscopic analysis of NMR and MS data, chiral HPLC analysis, J-based configuration analysis, and quantum chemical calculations of ECD, specific rotation, and NMR (with DP4+ probability analysis). Compound 3 showed inhibitory activity against some strains of pathogenic bacteria., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Cellular slime molds are excellent model organisms in the field of cell and developmental biology because of their simple developmental patterns. During our studies on the identification of bioactive molecules from secondary metabolites of cellular slime molds toward the development of novel pharmaceuticals, we revealed the structural diversity of secondary metabolites. Cellular slime molds grow by feeding on bacteria, such as Klebsiella aerogenes and Escherichia coli, without using medium components. Although changing the feeding bacteria is expected to affect dramatically the secondary metabolite production, the effect of the feeding bacteria on the production of secondary metabolites is not known. Herein, we report the isolation and structure elucidation of clavapyrone ( 1 ) from Dictyostelium clavatum , intermedipyrone ( 2 ) from D. magnum , and magnumiol ( 3 ) from D. intermedium . These compounds are not obtained from usual cultural conditions with Klebsiella aerogenes but obtained from coincubated conditions with Pseudomonas spp. The results demonstrate the diversity of the secondary metabolites of cellular slime molds and suggest that widening the range of feeding bacteria for cellular slime molds would increase their application potential in drug discovery.

A newly discovered trihydroxynaphthalenone derivative, epoxynaphthalenone ( 1 ) involving the condensation of ortho-hydroxyl groups into an epoxy structure, and a novel pyrone metabolite characterized as pyroneaceacid ( 2 ), were extracted from Talaromyces purpurpgenus , an endophytic fungus residing in Rhododendron molle . The structures of these compounds were elucidated through a comprehensive analysis of their NMR and HRESIMS data. The determination of absolute configurations was accomplished using electronic circular dichroism (ECD) calculations and CD spectra. Notably, these recently identified metabolites exhibited a moderate inhibitory activity against xanthine oxidase (XOD).

The plant Goniothalamus leiocarpus of the Annonaceae family is used as an alternative medicine in tropical regions. Applying high-speed counter current chromatography (HSCCC), eight new bioactive styrylpyrone isomers, including 6 R ,7 S ,8 R ,2' S -goniolactone B ( 1 ), 6 S ,7 S ,8 S ,2' S -goniolactone B ( 2 ), 6 R ,7 R ,8 R ,2' S -goniolactone B ( 3 ), 6 R ,7 S ,8 S ,2' S -goniolactone C ( 4 ), 6 R ,7 S ,8 R ,2' S -goniolactone C ( 5 ), 6 S ,7 R ,8 S ,2' S -goniolactone C ( 6 ), and two positional isomers, 6 R ,7 R ,8 R ,2' S -goniolactone G ( 7 ) and 6 S ,7 R ,8 R ,2' S -goniolactone G ( 8 ), were isolated from a chloroform fraction (2.1 g) of G. leiocarpus , which had a prominent spot by TLC analysis. The structures of the new compounds were elucidated by MS, NMR, IR, and UV spectra, and their absolute configurations were determined by Mosher's method, ECD, and X-ray diffraction analysis. The isolates are characteristic components found in plants of the genus Goniothalamus and consist of two structural moieties: a styrylpyrone and a dihydroflavone unit. The isolation of the eight new compounds demonstrates the effectiveness of HSCCC in separating the isomers of natural styrylpyrone. In a bioactivity assessment, compounds 1 and 6 exhibited cytotoxic effects against the human colon carcinoma cell lines LS513 and SW620 with IC 50 values ranging from 1.6 to 3.9 μM. Compounds 1 , 2 , 7 , and 8 showed significant synergistic activity against antibiotic-resistant Staphylococcus aureus strains.

A new α-pyrone analog, arthrifuranone A (1) was isolated from an EtOAc-extract of Arthrinium pseudosinense culture medium. The isolation workflow was guided by a Molecular Networking-based dereplication strategy. The chemical structure of the new compound was elucidated using MS and NMR spectroscopic techniques, and the absolute configuration was established by the Mosher's method and gauge-including atomic orbital NMR chemical shift calculations, followed by DP4 + analysis. The isolated compound was evaluated for its estrogenic activity using the MCF-7 estrogen responsive human breast cancer cells. Compound 1 showed estrogenic activity by increasing the proliferation of MCF-7 cells at the concentration of 3.125 μM via phosphorylation of estrogen receptor-α., (© 2021. The Author(s), under exclusive licence to the Japan Antibiotics Research Association.)

Three pairs of undescribed enantiomeric α-pyrone derivatives (1a/1b-3a/3b) and six undescribed congeners (4-9), were obtained from the fungus Alternaria brassicicola that was isolated from the fresh leaves of Siegesbeckia pubescens Makino (Compositae). The structures of these new compounds were characterized by extensive NMR spectroscopic and HRESIMS data, and their absolute configurations were further elucidated by a modified Mosher's method, chemical conversion, single-crystal X-ray diffraction analysis, and ECD calculations. This is the first report of three pairs of enantiomeric α-pyrone derivatives from the fungus A. brassicicola, and these enantiomers were successfully acquired from scalemic mixtures via chiral HPLC. Compounds 1a/1b-3a/3b and 4-9 were evaluated for the herbicidal activity against Echinochloa crusgalli, Setaria viridis, Portulaca oleracea, and Taraxacum mongolicum. At a concentration of 100 μg/mL, compounds 1a and 1b could significantly inhibit the germination of monocotyledon weed seeds (E. crusgalli and S. viridis) with inhibitory ratios ranging from 68.6 ± 6.4% to 84.2 ± 5.1%, which was equivalent to that of the positive control (glyphosate). The potential structure-herbicidal activity relationship of these compounds was also discussed. To a certain extent, the results of this study will attract great interest for the potential practical application of promising fungal metabolites, α-pyrone derivatives, as ecofriendly herbicides., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Ethnopharmacological Relevance: The edible plant Opuntia dillenii (Ker Gawl.) Haw. commonly known as Nagphana, belongs to the Cactaceae family. It is traditionally used to treat various ailments including inflammation, gastric ulcers, diabetes, hepatitis, asthma, whooping cough and intestinal spasm., Aim of the Study: Despite its traditional use in various countries, detailed toxicological studies of O. dillenii cladode are few. Thus in the current study, toxicity of O. dillenii cladode derived methanol extract, fractions and its α-pyrones: opuntiol and opuntioside have been addressed., Methods: The test agents were assessed using both in vitro and in vivo toxicity assays. MTT on human embryonic kidney cell line (HEK-293), tryphan blue exclusion in rat neutrophils, Cytokinesis-B block micronucleus (CBMN) in human lymphocytes and genomic DNA fragmentation using agarose gel electrophoresis were performed. In acute toxicity test, mice orally received extract (5 g/kg) for 7 days followed by measurements of relative organ weight, biochemical (blood profile, liver and kidney function test) and histological studies (liver and kidney) were carried out. Rat bone marrow micronucleus genotoxicity assay was also conducted., Results: O. dillenii derived test agents were non-cytotoxic and had no effect on the integrity of DNA. Methanol extract (5 g/kg) orally administered in mice did not cause any significant change in relative organ weights, biochemical parameters and liver and kidney histology as compared to vehicle control. In parallel, extract did not stimulate micronuclei formation in rat bone marrow polychromatic erythrocytes., Conclusion: These results led to conclude that edible O. dillenii extract is non-toxic via the oral route and appears to be non-cyto-, hepato-, nephro- or genotoxic, thereby supporting its safe traditional use against various ailments. Therefore, opuntiol and opuntioside may serve as lead compounds in designing new drug(s) derived from edible plants., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Two novel kojic acid derivatives, kojicones A and B (1 and 2), along with the precursors kojic acid (3) and (2R,4R)-4-hydroxy-5-methoxy-2,4-dimethyl-2- [(2R)-2-methylbutyryloxy]-5-cyclohexen-1,3-dione (4), were isolated from a fungal strain Aspergillus versicolor. Their structures and absolute configurations were accurately confirmed by HRESIMS data, NMR analysis, and electronic circular dichroism (ECD) calculations. Kojicones A and B were the first examples of kojic acid adducts with cyclohexen-1,3-dione possessing unprecedented tricycle skeletons. Compounds 1-3 were found to have inhibition on the NO production of murine RAW 264.7 cells. They can also reduce the mRNA expression of four cytokines (IL-6, IL-1β, TNF-α, and iNOS) and promote the expression of IL-4 at 20 μM. Moreover, kojic acid (3) could treat the DSS (dextran sulfate sodium)-induced colitis on mice with the effectiveness similar to that of the positive control. The results suggested that kojic acid and its derivatives could be a promising anti-inflammatory source for the medicinal and cosmetic industry., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Aspergillus niger metabolites exhibited a wide range of biological properties including antioxidant and neuro-protective effects and some physical properties as green synthesis of silver nanoparticles AgNP. The present study presents a novel evidence for the various biological activities of green synthesized AgNPs. For the first time, some isolated naphtho-γ-pyrones from marine-derived Aspergillus niger, flavasperone (1), rubrofusarin B (2), aurasperone A (3), fonsecinone A (4) in addition to one alkaloid aspernigrin A (7) were invistigated for their inhibitory activity of acetylcholine esterase AChE, a hallmark of Alzheimer's disease (AD). The ability to synthesize AgNPs by compounds 3, 4 and 7 has been also tested for the first time. Green synthesized AgNPs were well-dispersed, and their size was ranging from 8-30 nm in diameter, their morphology was obviously spherical capped with the organic compounds. Further biological evaluation of their AChE inhibitory activity was compared to the parent compounds. AgNps dramatically increased the inhibitory activity of Compounds 4, 3 and 7 by 84, 16 and 13 fold, respectively to be more potent than galanthamine as a positive control with IC50 value of 1.43 compared to 0.089, 0.311 and 1.53 of AgNPs of Compounds 4, 3 and 7, respectively. Also compound 2 showed moderate inhibitory activity. This is could be probably explained by closer fitting to the active sites or the synergistic effect of the stabilized AgNPs by the organic compouds. These results, in addition to other intrinsic chemical and biological properties of naphtho-γ-pyrones, suggest that the latter could be further explored with a view towards other neuroprotective studies for alleviating AD., Competing Interests: The authors have declared that no competing interests exist.

Eight new complex flavanones with a novel linkage, cryptoyunnanones A-H ( 1 - 8 ), together with four known α-pyrones, were isolated from the leaves and twigs of Cryptocarya yunnanensis . The structures of 1 - 8 including their absolute configurations were characterized by spectroscopic data analysis and single-crystal X-ray crystallography. Plausible biosynthetic pathways for the formation of compounds 1 - 8 were proposed. Compounds 1 - 4 exhibited cytotoxicity against HCT-116, MDA-MB-231, and PC-3 cancer cells with IC 50 values from 6.4 to 9.1 μM.

Six new α-pyrone polyketides, penipyrols C-G (1-5) and methyl-penipyrol A (6), together with one biogenetically related known compound, penipyrol A (7), were isolated from the extract of fungus Penicillium sp. HDN-11-131. Their structures including the absolute configurations were established by extensive spectroscopic analysis, Mosher's method, and ECD calculations as well as biogenic considerations. Compounds 1-4 possess a rare skeleton featuring γ-butyrolactone linked to α-pyrone ring through double bond. Compound 1 can induce pancreatic β-cell regeneration in zebrafish at 10 μM, which demonstrated promising anti-diabetes potential., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Tyrosinase (TYR) is a type III copper oxidase present in fungi, plants and animals. The inhibitor of human TYR plays a vital role in pharmaceutical and cosmetic fields by preventing synthesis of melanin in the skin. To search for an effective TYR inhibitor from various plant extracts, a kinetic study of TYR inhibition was performed with mushroom TYR. Among Panax ginseng , Alpinia galanga , Vitis vinifera and Moringa oleifera , the extracts of V. vinifera seed, A. galanga rhizome and M. oleifera leaf reversibly inhibited TYR diphenolase activity with IC 50 values of 94.8 ± 0.2 µg/mL, 105.4 ± 0.2 µg/mL and 121.3 ± 0.4 µg/mL, respectively. Under the same conditions, the IC 50 values of the representative TYR inhibitors of ascorbic acid and kojic acid were found at 235.7 ± 1.0 and 192.3 ± 0.4 µg/mL, respectively. An inhibition kinetics study demonstrated mixed-type inhibition of TYR diphenolase by A. galanga and V. vinifera , whereas a rare uncompetitive inhibition pattern was found from M. oleifera with an inhibition constant of K ii 73 µg/mL. Phytochemical investigation by HPLC-MS proposed luteolin as a specific TYR diphenolase ES complex inhibitor, which was confirmed by the inhibition kinetics of luteolin. The results clearly showed that studying TYR inhibition kinetics with plant extract mixtures can be utilized for the screening of specific TYR inhibitors.

Swertiamarin, a seco-iridoid glycoside, is mainly found in Enicostemma littorale Blume ( E. littorale ) and exhibits therapeutic activities for various diseases. The present study aimed to provide a review of swertiamarin in terms of its phytochemistry, physicochemical properties, biosynthesis, pharmacology and therapeutic potential. Relevant literature was collected from several scientific databases, including PubMed, ScienceDirect, Scopus and Google Scholar, between 1990 and the present. This review included the distribution of swertiamarin in medicinal plants and its isolation, characterization, physicochemical properties and possible biosynthetic pathways. A comprehensive summary of the pharmacological activities, therapeutic potential and metabolic pathways of swertiamarin was also included after careful screening and tabulation. Based on the reported evidence, swertiamarin meets all five of Lipinski's rules for drug-like properties. Thereafter, the physicochemical properties of swertiamarin were detailed and analyzed. A simple and rapid method for isolating swertiamarin from E. littorale has been described. The present review proposed that swertiamarin may be biosynthesized by the mevalonate or nonmevalonate pathways, followed by the seco-iridoid pathway. It has also been found that swertiamarin is a potent compound with diverse pharmacological activities, including hepatoprotective, analgesic, anti-inflammatory, antiarthritis, antidiabetic, antioxidant, neuroprotective and gastroprotective activities. The anticancer activity of swertiamarin against different cancer cell lines has been recently reported. The underlying mechanisms of all these pharmacological effects are diverse and seem to involve the regulation of different molecular targets, including growth factors, inflammatory cytokines, protein kinases, apoptosis-related proteins, receptors and enzymes. Swertiamarin also modulates the activity of several transcription factors, and their signaling pathways in various pathological conditions are also discussed. Moreover, we have highlighted the toxicity profile, pharmacokinetics and possible structural modifications of swertiamarin. The pharmacological activities and therapeutic potential of swertiamarin have been extensively investigated. However, more advanced studies are required including clinical trials and studies on the bioavailability, permeability and administration of safe doses to offer swertiamarin as a novel candidate for future drug development., Competing Interests: The authors report no conflicts of interest in this work., (© 2021 Muhamad Fadzil et al.)

Five new α-pyrone derivatives, named penpolonin A-E (1-5), together with two known compounds (6-7) were acquired from the endophytic fungus Penicillium polonicum isolated from the roots of Camptotheca acuminata Decne. Their structures were established by combination of NMR and HRESIMS data and the absolute configurations of 1-5 were determined by NMR calculations and comparison of experimental and calculated ECD data. Compounds 3 and 7 exhibited moderate cytotoxicity against Hep-2, TU212 human laryngeal cancer cells with IC 50 values ranging from 31.6 to 45.1 μg/ml, compound 4 showed weak cytotoxicity against the Hep-2 and TU212 cell lines with IC 50 values of 69.2 and 68.7 μg/ml., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Increased blood glucose in diabetic individuals results in the formation of advanced glycation end products (AGEs), causing various adverse effects on kidney cells, thereby leading to diabetic nephropathy (DN). In this study, the antiglycative potential of Swertiamarin (SM) isolated from the methanolic extract of E. littorale was explored. The effect of SM on protein glycation was studied by incubating bovine serum albumin with fructose at 60 °C in the presence and absence of different concentrations of swertiamarin for 24 h. For comparative analysis, metformin was also used at similar concentrations as SM. Further, to understand the role of SM in preventing DN, in vitro studies using NRK-52E cells were done by treating cells with methylglyoxal (MG) in the presence and absence of SM. SM showed better antiglycative potential as compared to metformin. In addition, SM could prevent the MG mediated pathogenesis in DN by reducing levels of argpyrimidine, oxidative stress and epithelial mesenchymal transition in kidney cells. SM also downregulated the expression of interleukin-6, tumor necrosis factor-α and interleukin-1β. This study, for the first time, reports the antiglycative potential of SM and also provides novel insights into the molecular mechanisms by which SM prevents toxicity of MG on rat kidney cells.

Ustilaginoidin M 1 ( 1 ), a novel bis-naphtho-γ-pyrone, was isolated from the cultures of the fungus Villosiclava virens which was the pathogen of rice false smut disease. Its structure was elucidated by spectroscopic analysis and by comparison of its physical and spectroscopic data with the literature. Compound 1 was tested for its cytotoxicity against five human cancer cell lines.

In the present study, hydroxy-2-methyl-4H-pyran-4-one was isolated from the methanol root extract of Senecio laetus and was identified by FT-IR, 1 H, 13 C NMR and GC-MS. The larvicidal potential of the compound 3-hydroxy-2-methyl-4H-pyran-4-one was evaluated against the 4 th instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus at concentrations ranging from 20 to 1.25 ppm under laboratory conditions. The compound showed 100% mortality at 20 ppm against all the tested mosquitoe species and the LC 50 and LC 90 values were 1.22 and 7.25 ppm ( An. stephensi) , 2.10 and 99.84 ppm ( Ae. aegypti) and 3.88 and 12.47 ppm ( Cx . quinquefasciatus), respectively after 24 h of exposure period. In silico molecular docking study results reflects that hydroxy-2-methyl-4H-pyran-4-one compound showed highest binding affinity with OBP of Cx. quinquefasciatus (Glide energy score - 7.3 kcal/mol -1) . The larvicidal activity of hydroxy-2-methyl-4H-pyran-4-one against tested mosquito species appears interesting and may be developed after toxicological and field evaluation.

One new secoiridoid compound swertiamarin B ( 1 ), along with a known compound lytanthosalin ( 2 ), were isolated from ethanol extract of the aerial parts of Swertia mussotii . Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All compounds were first isolated from the Swertia genus. Their antitumor activities were evaluated for four human tumor cell lines (HCT-116, HepG2, MGC-803 and A549). Compounds 1 and 2 showed excellent cytotoxic activities toward the MGC-803 cell lines with IC 50 values 3.61 and 12.04 μM, respectively.

The elusive targets and the multifactorial etiology of Parkinson's disease (PD) have hampered the discovery of a potent drug for PD. Furthermore, the presently available medications provide only symptomatic relief and have failed to mitigate the pathogenesis associated with PD. Therefore, the current study was aimed to evaluate the prospective of swertiamarin (SW), a secoiridoid glycoside isolated from a traditional medicinal plant, Enicostemma littorale Blume to ameliorate the characteristic features of PD in Caenorhabditis elegans. SW (25 μM) administration decreased the α-synuclein (α-syn) deposition, inhibited apoptosis and increased dopamine level mediated through upregulating the expression of genes linked to ceramide synthesis, mitochondrial morphology and function regulation, fatty acid desaturase genes along with stress responsive MAPK (mitogen-activated protein kinase) pathway genes. The neuroprotective effect of SW was evident from the robust reduction of 6-hydroxydopamine (6-OHDA) induced dopaminergic neurodegeneration independent of dopamine transporter (dat-1). SW mediated translational regulation of MAPK pathway genes was observed through increase expression of SKN-1 and GST-4. Further, in-silico molecular docking analysis of SW with C. elegans MEK-1 showed a promising binding affinity affirming the in-vivo results. Overall, these novel finding supports that SW is a possible lead for drug development against the multi- factorial PD pathologies., (Copyright © 2021. Published by Elsevier Inc.)

Many natural products with extraordinary chemical structures and brilliant biological activities have been obtained from marine organisms. We have investigated such fascinating bioactive molecules, exemplified by the potent marine toxin palytoxin and the antitumor molecule halichondrin B, which has been developed as the anticancer drug Halaven®, to explore novel frontiers in organic chemistry and bioscience. Working within the traditional discipline, we have sought to acquire a deeper understanding of biological phenomena. We introduce here our major work along with up-todate topics. We isolated yoshinone A from marine cyanobacteria and completed a gram-scale synthesis. Yoshinone A is a novel polyketide that inhibited the differentiation of 3T3-L1 cells into adipocytes without significant cytotoxicity. The detailed mechanisms of action will be elucidated via further experiments in vitro and in vivo. In this study, we explore the true producers of okadaic acid and halichondrin B by immunostaining of Halichondria okadai with an antibody that was prepared using these natural products as an antigen. We will analyze isolated symbionts and reveal biosynthetic pathways., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Bioassay-guided fractionation of a cytotoxic extract derived from a solid potato dextrose agar (PDA) culture of Teratosphaeria sp. AK1128, a fungal endophyte of Equisetum arvense , afforded three new naphtho-γ-pyrone dimers, teratopyrones A-C ( 1 - 3 ), together with five known naphtho-γ-pyrones, aurasperone B ( 4 ), aurasperone C ( 5 ), aurasperone F ( 6 ), nigerasperone A ( 7 ), and fonsecin B ( 8 ), and two known diketopiperazines, asperazine ( 9 ) and isorugulosuvine ( 10 ). The structures of 1 - 3 were determined on the basis of their spectroscopic data. Cytotoxicity assay revealed that nigerasperone A ( 7 ) was moderately active against the cancer cell lines PC-3M (human metastatic prostate cancer), NCI-H460 (human non-small cell lung cancer), SF-268 (human CNS glioma), and MCF-7 (human breast cancer), with IC 50 s ranging from 2.37 to 4.12 μM while other metabolites exhibited no cytotoxic activity up to a concentration of 5.0 μM.

One new dihydrobenzofuran neolignan, patrinianeolignan I, two new monoterpenes, 6,7-dehydrodissectol A and patriniaol A, and a new γ-pyrone derivative, hydroxymaltol 3-O-(6'-O-trans-caffeoyl)-β-D-glucopyranoside, along with fifteen known lignans, eight known monoterpenes, and two known γ-pyrone derivatives, were isolated from the whole plant of Patrinia scabiosifolia. Their structures were elucidated by 1D- and 2D-NMR and HR-ESI-MS analysis. The absolute configuration of patrinianeolignan I was confirmed by circular dichroism (CD) spectrum. All compounds were evaluated in vitro for their cytotoxic activity against HCT-116 cells. The results showed that compounds patriniaol A and eudesmin exhibited moderate cytotoxicity against HCT-116 cells with IC 50 values of 42.23 μM and 41.92 μM, respectively., (© 2020 Wiley-VHCA AG, Zurich, Switzerland.)

A new griseofulvin derivative, eupenigriseofulvin ( 1 ), together with six known compounds, griseofulvin ( 2 ), dechlorogriseofluvin ( 3 ), dechloroisogriseofulvin ( 4 ), trichopyrone ( 5 ), 2-(4-hydroxyphenyl)-ethanol ( 6 ), and 1-phenylethane-1,2-diol ( 7 ), were isolated from the EtOAc extract of Eupenicillium sp. SCSIO41208. The structures of these compounds were elucidated by spectroscopic methods including NMR and mass spectrometry. The absolute configuration of 1 was determined on the basis of electronic circular dichroism (ECD) data analysis.

A new 6-benzyl-γ-pyrone ( 1 ), named aspergyllone was isolated from the culture filtrates of an endolichenic fungus Aspergillus niger Tiegh, obtained from lichen thallus Parmotrema ravum (Krog & Swinscow) Serus, collected in India. 1 was isolated for the first time from an endolichenic fungus together with six other known metabolites identified as aurasperones A ( 2 ) and D ( 3 ), asperpyrone A ( 4 ), fonsecinone A ( 5 ), carbonarone A ( 6 ) and pyrophen ( 7 ). The compounds were tested against a panel of human, plant, food borne and fish pathogens. Aspergyllone showed strong selective antifungal activity against Candida parapsilosis (Ashford) Langeron & Talice, with an IC 50 of 52 µg/mL. Aurasperone A and pyrophen showed moderate to strong antimicrobial activity inhibiting seven different test pathogens, being pyrophen active with IC 50 ranging from 35 to 97 µg/mL.[Formula: see text].

Chemical epigenetic modification on a marine-derived fungus Aspergillus terreus RA2905 using a histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA), resulted in a significantly changed metabolic profile. A chemical investigation of its ethyl acetate (EtOAc) extract led to the isolation of a racemate of benzyl furanone racemate (±)- 1 , which further separated chirally as a pair of new enantiomers, (+)- and (-)-asperfuranone ( 1 ), together with two new benzyl pyrones, asperpyranones A ( 2 ) and B ( 3 ). Their structures were elucidated by analysis of the comprehensive spectroscopic data, including one-dimensional (1D) and two-dimensional (2D) NMR, and HRESIMS. The absolute configurations were determined by electronic circular dichroism (ECD) calculation and single-crystal X-ray crystallographic experiment. The structures with benzyl furanone or benzyl pyrone skeletons were discovered from natural products for the first time. Compounds (±)- 1 , (+)- 1 , (-)- 1 , and 2 displayed the antifungal activities against Candida albicans with MIC values of 32, 16, 64, and 64 μg/mL and PTP1B inhibitory activities with the IC 50 values of 45.79, 17.32, 35.50, and 42.32 μM, respectively. Compound 2 exhibited antibacterial activity against Pseudomonas aeruginosa with the MIC value of 32 μg/mL.

A new bis-γ-pyrone polypropionate, 4,16-di- epi -onchidiol ( 1 ), along with three known related compounds ( 2 - 4 ) were isolated from the marine pulmonate mollusk Onchidium sp. The structure of compound 1 was elucidated by extensive spectroscopic analysis and by comparison the NMR data with its stereoisomers 2 - 4 , whereas its absolute configuration was determined by the combination of X-ray diffraction analysis and TDDFT-ECD calculation. In bioassay, the isolated compounds exhibited broad cytotoxicity against several cancer cell lines with IC 50 values ranging from 24.6 to 88.5μM.

Three new 5,6-dihydro-α-pyrones derivatives, named (S)-rugulactone (1) pulchrinervialactone A (2), and pulchrinervialactone B (4), along with one known pyrone, cryptobrachytone C (3), and three known amide derivatives (5-7) have been isolated from the leaves of Cryptocarya pulchrinervia. The structures of 1-7 were elucidated based on extensive spectroscopic data and comparison with literatures. The configurations of compounds 3 and 4 were established by single crystal X-ray diffraction analysis. This is also the first report in finding (S)-rugulactone (1) as a natural product. In addition, the preliminary cytotoxic activity of the isolated compounds was evaluated against P-388 cells using the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. All the pyrones, except compound 4, were active significantly inhibiting the growth of P-388 cells, while the amides derivatives (5-7) showed moderate to weak activities. Therefore, compounds 1-3 could be potentially examined further for anticancer agents.

Two new compounds, versicolones A and B ( 1 and 2 ), and three known pyrone derivatives ( 3 - 5 ) were isolated from the insect-associated fungus Aspergillus versicolor . Their structures were elucidated through a combination of HRESIMS and NMR spectroscopic analysis. Versicolone A ( 1 ) was revealed as a coumarin derivative with the rare 5-alkyl side chain substitution. Compound 5 exhibited significant antioxidant activity with EC 50 value of 8.0 μM in the ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) assay, which was more than 2-fold potency of the positive control trolox.

A new γ -pyrone derivative, acrepyrone A ( 1 ), and three known sorbicillinoids, trichodimerol ( 2 ), dihydrotrichodimerol ( 3 ) and tetrahydrotrichodimerol ( 4 ) were isolated from an endophytic fungus, Acremonium citrinum SS-g13, harboured in the roots of the Chinese medicinal plant Fructus mori. Their structures were determined by analysing MS, NMR, and ECD data. Compound 1 was evaluated for its cytotoxic effect, antibacterial activity and quorum sensing inhibitory potential.

Chemical epigenetic manipulation was applied to explore secondary metabolite of an endophytic fungus Penicillium herquei , which was obtained from the fruiting body of Cordyceps sinensis , and three previously undescribed polyketides with pyran-2-one scaffold were isolated from its fermentation broth containing 10 mg/L 5-aza-2-deoxycytidine (a frequently-used DNA methyltransferase inhibitor). The structures of these new compounds were identified by extensive spectroscopic analyses, and their absolute configurations were elucidated by quantum chemical ECD calculations.

Three new compounds, including two new 3,4,6-trisubstituted α-pyrone derivatives, chrysopyrones A and B (1 and 2), and one new indolyl diketopiperazine derivative, penilline C (3), along with twelve known compounds (4-15), were isolated and identified from the fungus Penicillium chrysogenum SCSIO 07007, separated from deep-sea hydrothermal vent environment sample collected from the Western Atlantic. Their structures and absolute configurations were determined by extensive spectroscopic analysis and electronic circular dichroism (ECD) calculations. All of the isolated compounds (1-15) were evaluated for their cytotoxic, antibacterial activities and enzyme inhibitory activities against acetylcholinesterase (AChE), α-glycosidase, and protein tyrosine phosphatase 1B (PTP1B). Among them, new compounds chrysopyrones A and B (1 and 2) displayed obvious inhibitory activities against PTP1B with IC 50 values of 9.32 and 27.8 μg/mL, respectively. Furthermore, molecular docking was performed to investigate the inside perspective of the action in PTP1B enzyme., 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 Inc. All rights reserved.)

A search for bioactive secondary metabolites from the endophytic fungus Fusarium chlamydosporum , isolated from the root of Suaeda glauca , led to the isolation of three indole derivatives ( 1-3 ), three cyclohexadepsipeptides ( 4-6 ), and four pyrones ( 7-10 ). The structures of new ( 1 ) and known compounds ( 2-10 ) were elucidated on the basis of extensive spectroscopic analysis. All these compounds were evaluated for phytotoxic, antimicrobial activities, and brine shrimp lethality. Compound 1 showed significant phytotoxic activity against the radicle growth of Echinochloa crusgalli , even better than the positive control of 2,4-D. Cyclohexadepsipeptides ( 4-6 ) and pyrones ( 7-10 ) exhibited brine shrimp lethality, especially 4 and 7 with the LD 50 values of 2.78 and 7.40 μg mL -1 , respectively, better than the positive control.

Two new α -pyrones, fupyrones A and B ( 1 and 2 ) and a biosynthetically related known α -pyrone, 4-methyl-5,6-dihydro-2 H -pyran-2-one ( 3 ), were isolated from an endophytic fungus, Fusarium sp. F20, harbored in the stems of the Chinese medicinal plant Mahonia fortunei . Their structures were determined on the basis of spectroscopic data including MS and NMR. The antibacterial efficacies of compounds 1 - 3 were evaluated against four selected Gram-positive and Gram-negative bacteria, and their quorum sensing inhibitory activity was also investigated against the test organism, Chromobacterium violaceum .

Glutamate toxicity has been implicated in neuronal cell death in both acute CNS injury and in chronic diseases. In our search for neuroprotective agents obtained from natural sources that inhibit glutamate toxicity, an endophytic fungus, Fusarium solani JS-0169 isolated from the leaves of Morus alba , was found to show potent inhibitory activity. Chemical investigation of the cultures of the fungus JS-0169 afforded isolation of six compounds, including one new γ-pyrone (1), a known γ-pyrone, fusarester D (2), and four known naphthoquinones: karuquinone B (3), javanicin (4), solaniol (5), and fusarubin (6). To identify the protective effects of the isolated compounds (1-6), we assessed their inhibitory effect against glutamate-induced cytotoxicity in HT22 cells. Among the isolates, compound 6 showed significant neuroprotective activity on glutamate-mediated HT22 cell death. In addition, the informatics approach using in silico systems pharmacology identified that compound 6 may exert its neuroprotective effect by controlling the amount of ubiquinone. The results suggest that the metabolites produced by the endophyte Fusarium solani JS-0169 might be related to the neuroprotective activity of its host plant, M. alba .

Present study aimed for molecular docking, antiproliferative and anticonvulsant activities of swertiamarin isolated from the successive methanol extract of Enicostemma axillare. Molecular docking of swertiamarin on telomerase targets (PDB ID: 5UGW, 3DU6 and 4ERD), followed by antiproliferative activity on HEp2 and HT-29 cells by MTT and SRB assays. Also tested for anticonvulsant activity by pentylenetetrazole (PTZ, 80 mg/kg bw) induced convulsant. Molecular docking study predicted good total score of the swertiamarin with the selected targets. Swertiamarin possesses antiproliferative activity on HEp-2 and HT-29 cells with lower CTC 50 values. It also served as significant anticonvulsant agent with prolonged onset and reduced duration of the seizures. These results confirm that swertiamarin exhibited potential antiproliferative and anticonvulsant activities., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Hyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC 50 of 52.01 ± 0.64, 45.91 ± 0.02 μg/mL and 82.84 ± 0.03 μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6 ± 0.4 μg/mL) showed IC 50 sufficiently low to be considered as a drug prototype.

The objective of this study was to explore the effect of magnesium acetate (MA) addition on the endo-polyphenol yield by Phellinus baumii and establish a feasible additive strategy. The optimal three-point MA addition strategy (0.05 g/L concentration of MA added at 0 h and 6 h, 0.9 g/L concentration of MA added at 12 h) was employed to obtain maximum endo-polyphenol yield. The maximum endo-polyphenol production was reached at 1.22 g/L, which was 1.39-fold higher than that of the control. Additionally, the endo-polyphenol showed stronger antioxidant activity in vitro compared with the control, including DPPH· scavenging capacity (78.76%) and Trolox equivalent antioxidant capacity (TEAC) (32.28 μmol Trolox/g sample). HPLC analysis showed that the endo-polyphenol production of the crude ethanol extracts was significantly higher than that of the control. Hispidin was isolated and identified from the ethanol extract of the culture mycelia from Ph. baumii with the three-point MA addition strategy. Hispidin showed a strong ability to scavenge DPPH free radicals and TEAC, equivalent to positive (vitamin C) value of 89.41% and 75.98%, respectively. Furthermore, hispidin protected H2O2-induced PC12 cells injured by decreased oxidative stress level. These results indicated that the MA multi-stage addition strategy was dependable, and could be used to develop new natural antioxidants for foods or medicines.

Imbalance of osteoblast and osteoclast in adult leads to a variety of bone-related diseases, including osteoporosis. Thus, suppressing the activity of osteoclastic bone resorption becomes the main therapeutic strategy for osteoporosis. Asperpyrone A is a natural compound isolated from Aspergillus niger with various biological activities of antitumour, antimicrobial and antioxidant. The present study was designed to investigate the effects of Asperpyrone A on osteoclastogenesis and to explore its underlining mechanism. We found that Asperpyrone A inhibited RANKL-induced osteoclastogenesis in a dose-dependent manner when the concentration reached 1 µm, and with no cytotoxicity until the concentration reached to 10 µm. In addition, Asperpyrone A down-regulated the mRNA and protein expression of NFATc1, c-fos and V-ATPase-d2, as well as the mRNA expression of TRAcP and Ctsk. Furthermore, Asperpyrone A strongly attenuated the RNAKL-induced intracellular Ca 2+ oscillations and ROS (reactive oxygen species) production in the process of osteoclastogenesis and suppressed the activation of MAPK and NF-κB signalling pathways. Collectively, Asperpyrone A attenuates RANKL-induced osteoclast formation via suppressing NFATc1, Ca 2+ signalling and oxidative stress, as well as MAPK and NF-κB signalling pathways, indicating that this compound may become a potential candidate drug for the prevention or treatment of osteoporosis., (© 2019 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Spectinabilin (1), spectinabilin derivative (2), and a new analogue, 2-demethyl-spectinabilin (3) were isolated from the fermentation broth of a soil-borne Streptomyces spectabilis strain. The structure of the new compound was elucidated by a detailed spectroscopic data analysis including data from CD spectra. Spectinabilin (1) demonstrated cytotoxicity against five human cancer cell lines, with IC 50 values ranging from 18.7 ± 3.1 to 34.6 ± 4.7 μM, while derivatives 2 and 3 showed weak cytotoxicities. Notably, 1 inhibited the growth and proliferation of the hepatocellular carcinoma cell lines SMMC7721 and HepG2 in a time- and dose-dependent manner. Further study demonstrated that 1 caused G2/M phase cell cycle arrest in SMMC7721 and HepG2 cells through decreasing the protein levels of cyclin B1 and cdc2 as well as increasing that of p21. Compound 1 downregulated the protein expression of Bcl-2, upregulated Bax, and activated the cleavage of caspase-9 and -3 as a result of inducing apoptosis in SMMC7721 and HepG2 cells. Furthermore, the antitumor effect of 1 in SMMC7721 and HepG2 cells was mediated by the PI3K/AKT signaling pathway. In addition, 1 also suppressed tumor growth in vivo though inducing cell cycle arrest and apoptosis., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A consistent kojic acid producing fungal strain has been isolated from rice husk using glucose-peptone medium. The isolate was identified as Aspergillus sojae SSC-3 on 18S rDNA analysis. A. sojae was capable of producing substantially good amount of kojic acid, however the production was varying from batch to batch. In order to obtain consistent, repeated and high levels of kojic acid, monospore isolation procedures was adopted. The highest production of kojic acid obtained was 12 ± 2 g/L in 120 h with sucrose (10%) and yeast extract (0.5%) as carbon and nitrogen source respectively. The process was scale up to 10 L fermenter size which repeatedly resulted in the production of 18 ± 2 g/L of kojic acid in 96 h. Kojic acid was recovered (> 82%) from the fermentation broth with > 99% purity. Best to our knowledge this is the first report were kojic acid production is reported from Aspergillus sojae strain.

Pyrones comprise a structurally diverse class of compounds. Although they are widespread in nature, their specific physiological functions remain unknown in most cases. We recently described that triketide pyrones mediate the sulfotransfer in caprazamycin biosynthesis. Herein, we report the identification of conexipyrones A-C, three previously unrecognized tetra-substituted α-pyrones, from the soil actinobacterium Conexibacter woesei . Insights into their biosynthesis via a type III polyketide synthase were obtained by feeding studies using isotope-enriched precursors. In vitro assays employing the genetically associated 3'-phosphoadenosine-5'-phosphosulfate (PAPS)-dependent sulfotransferase CwoeST revealed conexipyrones as the enzymes' genuine sulfate acceptor substrates. Furthermore, conexipyrones were determined to function as sulfate shuttles in a two-enzyme assay, because their sulfated derivatives were accepted as donor molecules by the PAPS-independent arylsulfate sulfotransferase (ASST) Cpz4 to yield sulfated caprazamycin intermediates.

Two new spliceostatin analogs, designed as spliceostatins J and K (1 and 2), were isolated and identified from the culture of Pseudomonas sp., along with two known ones, FR901464 (3) and spliceostatin E (4). Their structures were elucidated by detailed interpretation of their spectroscopic data, especially 2D-NMR and HR-ESI-MS. Spliceostatin J (1) represented the first example of spliceostatins bearing an unusual hexahydrofuro[3,4-b]furan moiety. Biological assay showed all the isolated compounds except 1 displayed potent cytotoxic activities against two cancer cell lines (MDA-MB-231 and A-549). Structure-activity-relationship studies revealed that the tetrahydropyran ring in spliceostatin analogs was necessary for their bioactive retention., (© 2019 Wiley-VHCA AG, Zurich, Switzerland.)

Two new meroditerpene pyrones, chevalone F (1) and 11-hydroxychevalone E (2), a new tryptoquivaline analog, tryptoquivaline V (3) and a new brasiliamide analog, brasiliamide G (4), together with thirteen known compounds, chevalones A-C (5-7), chevalone E (8), 11-hydroxychevalone C (9), pyripyropene A (10), isochaetominine C (11), pyrrolobenzoxazine terpenoids CJ-12662 (12) and CJ-12663 (13), fischerindoline (14), eurochevalierine (15), 1,4-diacetyl-2,5-dibenzylpiperazine-3,7''-oxide (16) and lecanorin (17) were isolated from the fungus Neosartorya pseudofischeri. Their structures were established on the basis of spectroscopic evidence. Compound 2 showed weak antibacterial activity against Escherichia coli and Salmonella enterica serovar Typhimurium, whereas compounds 7, 12, 13 and 15 showed antibacterial activity against Bacillus cereus and Staphylococcus aureus. In addition, compounds 13 and 14 showed cytotoxicity against KB and MCF-7 cancer cell lines, as well as the Vero cell line., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Sopherone A (1) and B (2), two new biologically relevant dibenzo-α-pyrones, were isolated from the stems of Cassia sophera Linn. (Caesalpiniaceae). Their structures were elucidated by detailed analysis of their spectroscopic data, including 1D and 2D NMR., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Five new funicone derivatives, pinophilones A-E (1a/1b and 2-4), along with 18 biosynthetically related known analogues (5-22), were obtained from the culture of a mangrove sediment-derived fungus Penicillium pinophilum SCAU037. Their structures were established by analysis of 1D/2D NMR and MS data, while the absolute configurations of the new compounds were determined by ECD calculation based on time-dependent density functional theory (TD-DFT). The dihydrofuran moiety in 1a and 1b was first reported for funicone derivatives. Compound 22 exhibited antibacterial activity against Mycobacterium smegmatis and Staphylococcus aureus with IC 50 of 23.5 and 2.6 μM, respectively, while 16, 18 and 22 showed significant α-glucosidase inhibitory activity with IC 50 of 51.9, 78.4 and 33.8 μM, respectively., (Copyright © 2019. Published by Elsevier B.V.)