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Six previously undescribed diterpenoid glucosides, along with four known compounds, were isolated from the aerial parts of Sigesbeckia glabrescens. The structures and absolute configurations of undescribed compounds were elucidated using extensive spectroscopic techniques, ECD calculations and chemical methods. Compounds 1 and 8 exhibited anti-inflammatory activity against LPS-induced NO production in RAW 264.7 macrophages, with compound 8 demonstrating significant inhibitory activity compared to positive control minocycline, boasting an IC 50 value at 14.20 μM. [Display omitted] [ABSTRACT FROM AUTHOR]

Aspercitrininone A (1), a novel polyketide featuring an unprecedented tetracyclic 6/6/6/5 spiral skeleton, was obtained from the rice fermentation cultures of the fungus Aspergillus cristatus together with five known compounds (2 – 6). Their structures were determined by HRESIMS data, 1D and 2D NMR spectroscopic analysis, and electronic circular dichroism (ECD) calculations. Aspercitrininone A was revealed as a new type of C/D cycle spiral structure and an unusual addition product of o-quinoid form citrinin with 2-methylterrefuranone. Compounds 1 , 4 , and 5 exhibited potent antibacterial activities with minimal inhibitory concentration (MIC) values from 13.2 to 67.3 μg/mL against four strains of human pathogenic bacteria in vitro. [Display omitted] • A novel polyketide aspercitrininone A was isolated from rice cultures of Aspergillus cristatus. • Aspercitrininone A possessed an unprecedented tetracyclic 6/6/6/5 spiral skeleton. • It could be formed by o-quinoid form citrinin with 2-methylterrefuranone through Michael addition reaction. • Aspercitrininone A exhibited antibacterial activities. [ABSTRACT FROM AUTHOR]

Three undescribed compounds (1 – 3), including two butenolides and one indol alkaloids. Together with twenty-one known compounds (4 – 24) were isolated and identified from Lepidium obtusum Basin. Their structures were elucidated by spectroscopic analysis and ECD calculations. The isolated compounds were tested for their antimicrobial, antioxidant, and anti-inflammatory activities. Among them, compounds 11 , 12 , 14 , 21 and 23 showed moderated antimicrobial activities against (Candida albicans , E. coli , Staphylococcus aureus). Compounds 11 , 12 , 14 , 15 , 17 and 18 exhibited potent antioxidant activities against ABTS and DPPH. Compound 1 exhibited moderated anti-inflammatory activities. Compounds 4 – 24 were isolated from this plant for the first time. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract The investigation of the crude extract of leaves and bark of Pilocarpus pennatifolius Lemaire allowed isolated of a not yet described coumarin, together with three known coumarins (bergapten, xanthotoxin and dimethyl allyl xanthyletin), and a not yet described imidazole alkaloid. All structures were established by means of spectral analysis, including extensive 2D NMR studies. In addition, the alkaloid had its absolute stereochemistry determined by X-ray diffraction. Meanwhile, extracts and pure compounds were tested against various strains of bacteria and fungi, showing promising antimicrobial activities. We highlight the activities of crude bark methanol extract (CBME), of the leaf basic acetate fraction (LBAcF), and of compound 2 against the Gram negative bacteria Shigella flexneri (MICs = 7.8, 7.8 and 3.12 μg·mL−1, respectively), of compound 5 against the Gram positive Enterococcus fecalis (MIC = 1.56 μg·mL−1), and against two Gram negative bacteria Salmonella enteritidis (MIC = 1.56 μg·mL−1), and Pseudomonas aeruginosa (MIC = 6.25 μg·ml−1). On the other hand, CBME and compounds 3 – 5 showed excellent activity against the fungus Candida krusei with MICs of 15.6, 1.56, and 3.12 μg·mL−1 respectively, as actives or better than the antifungal standard fluconazole (MIC = 3.12 μg·mL−1). Graphical abstract Unlabelled Image Highlights • Coumarins from Pilocarpus pennatifolius • Absolute stereochemistry of pennatifoline A • Antimicrobial study of Pilocarpus pennatifolius [ABSTRACT FROM AUTHOR]

Panax notoginseng (Burk.) F. H. Chen belongs to the Araliaceae family. It has been used by traditional Chinese people in Northeast Asia for centuries as an antidiabetic, antioxidant, antitumor agent, etc. Endophytic or rhizospheric microorganisms play key roles in plant defense mechanisms, and they are essential in the discovery of pharmaceuticals and valuable new secondary metabolites. In particular, endophytic or rhizospheric microorganisms of traditional medicinal plants. To discover valuable new secondary metabolites from rhizosphere soil Streptomyces sp. SYP-A7185 of P. notoginseng , and to explore potential bioactivities and targets of metabolites protrusive function. The metabolites were obtained via column chromatography and identified by multiple spectroscopic analyses. The antitumor, antioxidant, antibacterial, and antiglycosidases effects of isolated metabolites were tested using 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyltetazolium bromide (MTT), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 96-well turbidimetric, and α -glucosidase inhibitory assays. The potential antitumor targets were predicted through network pharmacological approaches. The interactions between metabolites and target were verified by molecular docking and biolayer interferometry (BLI) assay. The effects of cancer cells migration were detected through wound healing assays in A549 and MCF-7. Other cellular validation experiments including reverse transcription-quantitative PCR (RT‒qPCR) and western blotting (WB) were used to confirm the hypothesis of network pharmacology. Five different chemotypes of anthraquinone derivatives (1 – 10), including six new compounds (3 , 6 – 10), were identified from Streptomyces sp. SYP-A7185. Compounds 1 – 6 and 9 displayed moderate to strong cytotoxicity on five human cancer cell lines (A549, HepG2, MCF-7, MDA-MD-231, and MGC-803). Moreover, matrix metalloproteinase-2 (MMP2) were predicted as a potential antitumor target of metabolites 1 – 6 and 9 by comprehensive network pharmacology analysis. Later, BLI assays revealed strong intermolecular interactions between MMP2 and antitumor metabolites, and molecular docking results showed the interaction of metabolites 1 – 6 and 9 with MMP2 was dependent on the crucial amino acid residues of LEU-83, ALA-84, LEU-117, HIS-131, PRO-135, GLY-136, ALA-140, PRO-141, TYR-143, and THR-144. These results implied that metabolites (1 – 6 and 9) might inhibit cancer cell migration besides cancer cell proliferation. After that, the cell wound healing assay showed that the cell migration processes were also inhibited after the treatments of compounds 1 and 3 in A549 and MCF-7 cells. In addition, the RT‒qPCR and WB results demonstrated that the gene expression levels of MMP2 were decreased after the treatment with compounds 1 and 3 in A549 and MCF-7 cells. Besides, compound 2 displayed moderate antioxidant activity (EC 50 , 27.43 μM), compounds 3 and 6 exhibited moderate antibacterial activity, and compound 3 inhibited α -glucosidase with an IC 50 value of 13.10 μM. Anthraquinone metabolites, from rhizosphere soil Streptomyces sp. of P. notoginseng , possess antitumor, antioxidant, antibacterial, and antiglycosidase activities. Moreover, metabolites 1 and 3 inhibit cancer cells migration through downregulating MMP2. [Display omitted] • Anthraquinone metabolites from rhizosphere soil Streptomyces of Chinese herbs Panax notoginseng (Burk.) F. H. Chen were studied. • Ten anthraquinone derivatives were isolated including six new compounds. • Anthraquinones (1 – 10) from Streptomyces sp. SYP-A7185 exerted various bioactivities. • Anthraquinone metabolites 1 and 3 inhibit cancer cells migration through downregulating MMP2. [ABSTRACT FROM AUTHOR]

Nine previously undescribed compounds including six tocopherol derivatives (1 – 6) and three acylphloroglucinol derivatives (7 – 9) were isolated and characterized from the plants of Dryopteris crassirhizoma. Their structures with absolute configurations were determined by extensive spectroscopic analyses, including IR, HRESIMS, NMR, and calculated electronic circular dichroism (ECD). Compounds 1 and 2 are the first tocopheroid derivatives possessing unique 2,5-dimethylcyclopent-4-ene-1,3-dione carbon skeleton, and compounds 3 – 6 were new 5a-norcyclopentenones having a spirofused bicyclic carbon skeleton. The biosynthetic pathway of compounds 1 – 6 was postulated. When combined with fluconazole (FLC), compound 3 showed significant antifungal activity against standard Candida albicans with MIC 50 value of 1.19 μg/mL (FLC: 3.41 μg/mL). Furthermore, the anti-plant pathogenic fungi and bacterial activities have been evaluated in vitro, compounds 5 and 8 showed anti- Verticillium dahlia and Sclerotinia sclerotiorum with MIC value of 50 μg/mL, respectively. Compounds 1 and 5 exhibited moderate antibacterial activities against Micrococcus luteus with MIC value of 50 μg/mL, respectively. [Display omitted] • Nine previously undescribed compounds were isolated from Dryopteris crassirhizoma. • The quantum calculation of electronic circular dichroism (ECD) data was applied for structure elucidation. • A biosynthesis of the tocopherol derivatives were assumed. • The antifungal and antibacterial activities of these compounds were evaluated. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Fagara tessmannii is a shrub of the African rainforests used to treat bacterial infections, cancers, swellings and inflammation. In the present study, the methanol extract from the leaves (FTL), bark (FTB), and roots (FTR) of this plant as well as fractions (FTR1-5) and compounds isolated from FTR namely β -sitosterol-3- O-β- d -glucopyranoside ( 1 ), nitidine chloride ( 2 ) and buesgenine ( 3 ), were tested for their antimicrobial activities against a panel of Gram-negative bacteria including multidrug resistant (MDR) phenotypes. Materials and methods The broth microdilution method was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the above samples; Column chromatography was used for the fractionation and purification of the roots extract whilst the chemical structures of compounds were determined using spectroscopic techniques. Results Results of the MIC determinations indicated that the crude extracts from the roots as well as fraction FTRa4 were active on all the 26 tested bacterial strains. MIC values below 100 µg/mL were obtained with roots, leaves and bark extract respectively against 30.8%, 15.4% and 11.5% tested bacteria. The lowest MIC value below of 8 µg/mL was obtained with extract from the roots against Escherichia coli MC100 strain. The lowest MIC value of 4 µg/mL was also obtained with compound 3 against E. coli AG102 and Klebsiella pneumoniae ATCC11296 Conclusions The present study demonstrates that F. tessmannii is a potential source of antimicrobial drugs to fight against MDR bacteria. Benzophenanthrine alkaloids 2 and 3 are the main antibacterial consituents of the roots of the plant. [ABSTRACT FROM AUTHOR]

A new prenylated isoflavan, iconisoflavan ( 1 ), and a new prenylated isoflav-3-ene, iconisoflaven ( 2 ) were isolated from the roots of Glycyrrhiza iconica together with four known ones namely ( 3S )-licoricidin ( 3 ), licorisoflavan A ( 4 ), topazolin ( 5 ) and glycycoumarin ( 6 ). The structures were elucidated on the basis of extensive spectroscopic analysis including 1D and 2D NMR as well as HR–MS. Furthermore, the absolute configurations of compounds 1 , 3 and 4 were established by electronic circular dichroism (ECD). All the isolated compounds ( 1 – 6 ) were evaluated for their in vitro antimicrobial activities against five pathogenic bacteria and one yeast ( Candida albicans ) using an in vitro microdilution method. Compounds 1 and 3 – 5 displayed significant activity against Salmonella typhimurium ATCC 13311 with MIC values ranging from 2 to 8 μg/mL. Additionally, all compounds were screened for their in vitro free radical scavenging activities using an in vitro microdilution DPPH assay spectrofotometrically. The tested compounds exhibited IC 50 values in the range of 0.18–0.56 mg/mL, suggesting an activity comparable with that of ascorbic acid (IC 50 : 0.07 mg/mL). To the best of our knowledge, the present study constitutes the first phytochemical and bioactivity investigation on G. iconica . [ABSTRACT FROM AUTHOR]

Three new polyketides named penialidins A–C ( 1 – 3 ), along with one known compound, citromycetin ( 4 ), were isolated from an endophytic fungus, Penicillium sp., harbored in the leaves of the Cameroonian medicinal plant Garcinia nobilis . Their structures were elucidated by means of spectroscopic and spectrometric methods (NMR and HRMS n ). The antibacterial efficacies of the new compounds ( 1 – 3 ) were tested against the clinically-important risk group 2 (RG2) bacterial strains of Staphylococcus aureus and Escherichia coli . The ecologically imposing strains of E. coli (RG1), Bacillus subtilis and Acinetobacter sp. BD4 were also included in the assay. Compound 3 exhibited pronounced activity against the clinically-relevant S. aureus as well as against B. subtilis comparable to that of the reference standard (streptomycin). Compound 2 was also highly-active against S. aureus . By comparing the structures of the three new compounds ( 1 – 3 ), it was revealed that altering the substitutions at C-10 and C-2 can significantly increase the antibacterial activity of 1 . [ABSTRACT FROM AUTHOR]

Tabernaecorymine A, an 18-normonoterpenoid indole alkaloid with conjugated (E)-3-aminoacrylaldehyde fragment was obtained from the stem bark of Tabernaemontana corymbosa. Its structure was elucidated by extensive spectroscopic data analyses, and further verified by ACD/structure elucidator, electronic circular dichroism (ECD) analyses and density functional theory (DFT) chemical shift predictions. The compound exhibited significant antibacterial bioactivity against Streptococcus dysgalactiae with an MIC value of 3.12 μ g/mL, which is better than the plant drug berberine. [Display omitted] • An 18-normonoterpenoid indole alkaloid was isolated from Tabernaemontana corymbosa. • Tabernaecorymine A (1) was determined by spectral data analysis, ACD/SE, ECD, and DFT synergistic algorithms. • Antibacterial activity of tabernaecorymine A (1) was evaluated. [ABSTRACT FROM AUTHOR]

Five undescribed carboxy-indole alkaloids with corynanthe skeleton, penduflorines A–E (1 – 3) as well as a voacangine- N -oxide alkaloid, tabernaemontine (4), were isolated along with eight other known compounds (5 – 12) from the trunk bark of Tabernaemontana penduliflora K. Schum (Apocynaceae). Their structures were determined by means of spectroscopic and spectrometric methods such as UV, IR, NMR and HR-ESI-MS. Antiplasmodial activities of new isolates were evaluated against two strains of Plasmodium falciparum 3D7 and Dd2 by the Sybr green I-based fluorescence assay setup. Those compounds showed good in vitro activities. Among them, penduflorines A and B (1a and 1b) as well as tabernaemontine (4) showed significant inhibitory activities against the two strains with IC 50 values ranged between 1.85 and 7.88 μg/mL. This is the first report of quaternary- N -indole alkaloids (1a , 1b , 2 , 3a , 3b and 4) occurring in the form of zwitterion from Tabernaemontana genus. [Display omitted] • Six undescribed MIAs were isolated from trunk bark of Tabernaemontana penduliflora. • All MIAs were identified as zwitterion salts and two of them seem to be an indistinguishable isomeric pairs. • New MIAs were determined by extensive spectroscopic method. • Antiplasmodial activity of the crude extract and new isolates was assayed. • Compounds 1 and 4 displayed potent antitplasmodial activity against two strains of Plasmodium falciparum. [ABSTRACT FROM AUTHOR]

Two novel sulfur-containing dibenzofurans, sorbusins A (1) and B (2), two unprecedented biphenyl glycosides, 2′-hydroxyaucuparin 2′- O - ɑ -L-rhamnoside (3) and noraucuparin 5- O - ɑ -L-rhamnoside (4), and four known analogues (5 – 8), were isolated from Sorbus pohuashanensis suspension cell induced by yeast extract. Their structures were elucidated based on spectroscopic analyses and quantum calculation of 13C NMR data. Structurally, compound 1 possessed a rare naturally occurring benzothiazole moiety and represents the first example of thiazole fused dibenzofuran. A plausible biosynthetic pathway for the sulfur-containing dibenzofurans is proposed. These dibenzofuran and biphenyl phytoalexins were evaluated for their antimicrobial activities against pathogenic fungi and drug-resistant bacteria. Compound 7 exhibited significant antibacterial activity against methicinllin-resistant Staphylococcus aureus with an MIC value of 3.13 μg/mL. [Display omitted] • Sulfur-containing dibenzofurans were isolated from Sorbus pohuashanensis suspension cell. • The quantum calculation of 13C NMR data was applied for structure elucidation. • This is the first example of naturally occurring thiazole fused dibenzofuran. • A plausible biosynthetic pathway for the sulfur-containing dibenzofurans is proposed. • The dibenzofuran and biphenyl phytoalexins were evaluated for their antifungal and antibacterial activities. [ABSTRACT FROM AUTHOR]

Two new norhopane derivatives namely 3β,6β,22-trihydroxy-7β,11α-di[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23)-ene (1) and 3β,6β,22-trihydroxy-7β-[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23)-ene (2) together with two previously reported compounds, including a norhopane, 3β,6β,11α-trihydroxy-7β-[(4-hydroxybenzoyl)oxy]-24-norhopa-4(23),17(21)-diene (3) and a norneohopane, (21αH)-24-norneohopa-4(23), 22(29)-diene-3β,6β,7β-triol 7-caffeate (4) were isolated from the root bark of Fagaropsis angolensis. Elucidation of their structures was achieved by spectroscopic (NMR, IR and UV) and spectrometric (HRESIMS) data and by comparison of these data with those of related compounds in the literature. Compounds 1–4 were evaluated for their anti-inflammatory activity by measuring the levels of cytokines, IL-1β, IL-2, GM-CSF and TNF-α in lipopolysaccharide (LPS) stimulated peripheral blood mononuclear cells (PBMC). All tested compounds decreased secretion of IL-1β and TNF-α. Compounds 2 and 4 caused significant decrease of the production of IL-2, GM-CSF and TNF-α compared to the reference drug, ibuprofen. These findings showed that the root barks of F. angolensis are rich source of norhopane derivatives and further provide a scientific rationale of using this plant in Kenyan folk medicine to relieve pain. Unlabelled Image [ABSTRACT FROM AUTHOR]

Five new 4-alkyl-5,7-dihydroxycoumarins, Mesuaferol G–K (1 – 5), together with four known 4-alkyl-5,7-dihydroxycoumarins (6 – 9) were isolated from the methanol extraction of the flowering buds of Mesua ferrea by flash extraction. Their structures were established on the basis of extensive analyses of HR-ESI-MS, UV, IR and NMR methods, the absolute configurations were confirmed by the Mosher's method and circular dichroism (CD) measurement and theoretical calculation (ECD) methods. Additionally, a putative biogenetic relationship of these compounds was also proposed. The cytotoxicity of all these isolates against HepG2, MCF-7 and Hela cancer cell lines was evaluated. In MCF-7 and Hela cell lines, all compound s exhibited strong activity (IC 50 in the range of 3.21–13.54 μM and 4.69–14.47 μM, respectively), while almost all compound s showed moderate cytotoxic activities against HepG2 cell lines. Unlabelled Image [ABSTRACT FROM AUTHOR]