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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]

Four previously unreported diterpenoids including three ent -atisanes (1–3) and one ent -abietane (4), along with one known linear triterpenoid (5) and five known diterpenoids including four myrsinanes (6–9), and one abietane (10) have been isolated from the roots of Euphorbia spinidens Bornm. ex Prokh. The structures were determined on the basis of extensive spectroscopic analyses including HR-ESI-MS, 1D and 2D NMR and comparison of the data with those reported in the literature. Antimicrobial potential of isolated compounds were also evaluated. Guionianol B (10) showed good antibacterial activity against Staphylococcus aureus and Bacillus subtilis with MIC value of 6.25 μg/mL. [Display omitted] [ABSTRACT FROM AUTHOR]

Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3–6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C 12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2 H)-one core with an α , β -unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 μg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 μg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities. [Display omitted] • Two novel fungal polyketides were identified from the endophytic fungus Phoma sp. YUD17001. • Phometide A possess an unusual tetrahydrobenzofuran-3(2 H)-one functionality. • Phometide B is a novel polyketone containing a 2-pentylcycloheptan-1-one scaffold. • Phometides A and B demonstrated antimicrobial activity against S. aureus and C. albicans , respectively. [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]

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]

Chemical analysis of extracts from cultures of the plant pathogenic fungus Cytospora sp. strain CCTU A309 collected in Iran led to the isolation of two previously unreported heptanedioic acid derivatives namely (2 R ,3 S) 2-hydroxy-3-phenyl-4-oxoheptanedioic acid (1) and (2 S ,3 S) 2-hydroxy-3-phenyl-4-oxoheptanedioic acid (2) as diastereomers, four previously undescribed prenylated p -terphenyl quinones 3 – 6 in addition to five known metabolites. Their structures were elucidated on the basis of extensive spectroscopic analysis and high-resolution mass spectrometry. For metabolites 1 and 2 , the absolute configurations at C-2 were deduced from comparison of the 1H NMR difference of their (S)- and (R)-phenylglycine methyl ester derivatives while the relative configurations were tentatively assigned by a J -based analysis and confirmed by comparison of 13C chemical shifts to literature data. The isolated compounds were tested for their cytotoxic, antimicrobial (including biofilm inhibition), antiviral, and nematicidal activities. While only moderate antimicrobial effects were observed, the terphenyl quinone derivatives 3 – 6 and leucomelone (10) exhibited significant cytotoxicity against the mouse fibroblast L929 and cervix carcinoma KB-3-1 cell lines with IC 50 values ranging from 2.4 to 26 μg/mL. Furthermore, metabolites 4–6 showed interesting antiviral activity against hepatitis C virus (HCV). Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract The coumarin–orthoaminophenol derivative was prepared under mild conditions. Based on crystallographic structure, IR and Raman, 1H and 13C NMR spectra the most applicable theoretical method was determined to be B3LYP-D3BJ. The stability and reactivity parameters were calculated, in the framework of NBO, QTAIM and Fukui functions, form the optimized structure. This reactivity was then probed in biological systems. The antimicrobial activity towards four bacteria and three fungi species was examined and activity was proven. In vitro cytotoxic effects, against human epithelial colorectal carcinoma HCT-116 and human healthy lung MRC-5 cell lines, of the investigated substance are also tested. Compound showed significant cytotoxic effects on HCT-116 cells, while on MRC-5 cells showed no cytotoxic effects. The effect of hydroxy group in ortho -position on the overall reactivity of molecule was examined through molecular docking with Glutathione-S-transferases. Graphical Abstract Unlabelled Image Highlights • The cumarine derivative with o -aminophenol was synthesized under mild conditions. • The structure and spectroscopic properties of compound 3 are confirmed by DFT. • The MIC and IZ values of 3 are comparable to the commercially active drugs • Investigated substance revealed surprising effect on cancer cells HCT-116. • Possible interactions between 3 and Glutathione-S-transferase were revealed by MD. [ABSTRACT FROM AUTHOR]

Highlights • Five new zinc(II) 3-aminobenzoates were synthesized and characterized by infrared spectroscopy and elemental analysis. • Thermal decomposition of all complexes was studied by thermogravimetric analysis and differential thermal analysis. • Antimicrobial activity of the prepared complexes against bacteria, yeast and filamentous fungi was evaluated. • Influence of the amino group position on the benzene ring on the antimicrobial activity of aminobenzoates was revealed. Abstract Zinc(II) 3-aminobenzoate (3-NH 2 benz) as well as four new coordination compounds containing ligands L (thiourea – tu , nicotinamide – nad ; isonicotinamide – inad ; N,N -diethylnicotinamide – dnad) with general formula of [Zn(3-NH 2 benz) 2 L 2 ] were synthesized and characterized by elemental analysis and IR spectroscopy. Thermoanalytical methods (TG/DTG, DTA) were used in order to compare the thermal decomposition of synthesized compounds with previously prepared 2- and 4-aminobenzoates. The intermediates and the final product of thermal decomposition were proved by spectroscopic methods. The antimicrobial activity of the zinc(II) 3-aminobenzoate complexes against various strains of bacteria, yeasts and filamentous fungi was determined and compared with 2- and 4-aminobenzoates as well. According to obtained results complexes with thiourea and N,N -diethylnicotinamide exhibit activity towards filamentous fungi R. oryzae , and A. Alternata, yeast C. Albicans , as well as bacteria S. aureus. [ABSTRACT FROM AUTHOR]

Abstract N -myristoylation (Myr) is an eukaryotic N -terminal co- or post-translational protein modification in which the enzyme N -myristoyltransferase (NMT) transfers a fatty acid (C14:0) to the N -terminal glycine residues of several cellular key proteins. Depending on the cellular context, NMT may serve as a molecular target in anticancer or anti-infectious therapy, and drugs that inhibit this enzyme may be useful in the treatment of cancer or infectious diseases. As part of an on-going project to identify natural Homo sapiens N -myristoyltransferase 1 inhibitors (HsNMT1), two ellagitannins, punicalagin (1) and isoterchebulin (2), along with eschweilenol C (3) and ellagic acid (4) were isolated from the bark of Terminalia bentzoë (L.) L. f. subsp. bentzoë. Their structures were determined by means of spectroscopic analyses and comparison with literature data. Punicalagin (1) and isoterchebulin (2) showed significant inhibitory activity towards HsNMT1, and also against Plasmodium falciparum NMT (PfNMT) both in vitro and in cellulo , opening alternative paths for new NMT inhibitors development. This is the first report identifying natural products from a botanical source as inhibitors of HsNMT and PfNMT. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract Five new homoisoflavonoid derivatives, including three meta -homoisoflavanes (1–3), one homoisoflavanone (4), and one homoisoflavan (5), along with five known analogues (6–10), were isolated from the red resin of Dracaena cochinchinensis (Chinese dragon's blood). Their structures were elucidated by analysis of spectroscopic data (1D and 2D NMR, IR, and HRESIMS). The absolute configuration of compound 1 was determined by single-crystal X-ray crystallographic analysis, and those of 2–5 were established on the basis of experimental and computed ECD data. Compounds 4 , 6 , and 9 exhibited moderate inhibition of nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells with IC 50 values of 60.4 – 75.6 μM. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract A total of 180 fungal isolates, belonging to 20 genera and 47 species, were obtained from the roots, stems and leaves of Panax notoginseng. One isolate, the endophytic fungus Penicillium janthinellum SYPF 7899, displayed the strongest antibacterial activity and was studied for its production of secondary metabolites. In total, three new compounds, including rotational isomers 1a, 1b and 2 were isolated from the solid cultures of P. janthinellum , as well as eight known compounds (3 − 10). These structures were determined on the basis of 1D, 2D NMR and electronic circular dichroism (ECD) spectroscopic analyses as well as theoretical calculations. Compound 1 exhibited significant inhibitory activities against Bacillus subtilis and Staphylococcus aureus with MIC values of 15 and 18 μg/ml, respectively. The other compounds showed moderate or weak activities. In addition, morphological observation showed the rod-shaped cells of B. subtilis growing into long filaments, which reached 1.5- to 2-fold of the length of the original cells after treatment with compound 1. The coccoid cells of S. aureus exhibited a similar response and swelled to a 2-fold volume after treatment with compound 1. In silico molecular docking was explored to study the binding interactions between the compounds and the active sites of filamentous temperature-sensitive protein Z (FtsZ) from B. subtilis and S. aureus. Compound 1a, 1b and 2 showed high binding energies, strong H-bond interactions and hydrophobic interactions with FtsZ. Based on the antimicrobial activities, cellular phenotype observation and docking studies, compound 1 is considered to be a promising antimicrobial inhibitor of FtsZ. Graphical Abstract Unlabelled Image [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]

A chemical investigation on the 80% EtOH extract of the aerial parts of Kopsia fruticosa led to five new indole alkaloids, kopsifolines G-K ( 1–5 ), and one known alkaloid, kopsifoline A ( 6 ). Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D ( 1 H- 1 H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated components were evaluated in vitro for cytotoxic activities against seven tumor cell lines, antimicrobial activities against two Gram-positive bacteria and five Gram-negative bacteria, and antifungal activities against five pathogens. As a result, alkaloids 3 – 5 exhibited some cytotoxicity against all of seven tested tumor cell lines (HS-1, HS-4, SCL-1, A431, BGC-823, MCF-7, and W480) with IC 50 values of 11.8–13.8, 10.3–12.5, and 7.3–9.5 μM, respectively. Alkaloids 3–5 also possessed significant antimicrobial and antifungal activities which was reported for the first time for the alkaloids isolated from Kopsia genus. [ABSTRACT FROM AUTHOR]

Four new phenylisotertronic acids ( 1a/1b , 2a , and 3a ) were isolated from a TCM endophytic fungal strain Phyllosticta sp. J13-2-12Y obtained from the leaves of Acorus tatarinowii , along with two known ones ( 2b and 3b ). Compounds 1 − 3 all existed as mixtures of enantiomers, and their corresponding optically pure enantiomers were successfully isolated by chiral HPLC. The structures of isolated compounds were determined by comprehensive spectroscopic analyses and X-ray diffraction. Their absolute configurations were determined by ECD experiments and quantum chemical calculations. In addition, the antimicrobial activities and the cytotoxicities of these three pairs of optically pure enantiomers ( 1a/1b , 2a / 2b , and 3a/3b ) had been evaluated. [ABSTRACT FROM AUTHOR]

Tridentate Schiff's base (HL) ligand was synthesized via condensation of salicylaldehyde and 3-hydroxypyridin-2-yliminomethyl-4H-chromen-4-one and their corresponding Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized. The isolated solid complexes were characterized by elemental analyses, molar conductance, spectral (IR, UV–Vis, 1 H NMR), magnetic moment, EPR, and thermal measurements. The IR spectra showed that HL was coordinated to the metal ions in tridentate manner with O 2 N donor sites of the azomethine N, deprotonated phenolic-OH and carbonyl-O. The activation of thermodynamic parameters are calculated using Coast-Redfern and Horowitz–Metzger (HM). The octahedral geometry of the complexes is confirmed using DFT method from DMOL 3 calculations, UV–Vis and magnetic moment measurements, ESR and ligand field parameters. Antioxidant activities have also been performed for all the compounds. The investigated ligand and metal complexes were screened for their in-vitro antimicrobial activities against different types of fungal and bacterial strains. The resulting data assert on the inspected compounds as a highly promising bactericides and fungicides. The antitumor activities of all inspected compounds were evaluated towards human liver Carcinoma (HepG2) cell line. [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]

Schiff bases synthesised from the condensation of 2-(hydroxy)naphthaldehyde and sulfonamides (sufathiazole (STZ), sulfapyridine (SPY), sulfadiazine (SDZ), sulfamerazine (SMZ) and sulfaguanidine (SGN)) are characterized by different spectroscopic data (FTIR, UV–Vis, Mass, NMR) and two of them, (E)-4-(((2-hydroxynaphthalen-1-yl)methylene)amino)- N -(thiazol-2-yl)benzenesulfonamide ( 1a ) and (E)- N -(diaminomethylene)-4-(((2-hydroxynaphthalen-1-yl)methylene)amino)benzenesulfonamide ( 1e ) have been confirmed by single crystal X-ray structure determination. Antimicrobial activities of the Schiff bases have been evaluated against certified and resistant Gram positive ( Staphylococcus aureus , Enterococcus facelis ) and Gram negative ( Streptococcus pyogenes , Salmonella typhi , Shigella dysenteriae, Shigella flexneri, Klebsiella pneumonia ) pathogens. Performance of Schiff base against the resistant pathogens are better than standard stain and MIC data lie 32–128 μg/ml while parent sulfonamides are effectively inactive (MIC >512 μg/ml). The DFT optimized structures of the Schiff bases have been used to accomplish molecular docking studies with DHPS (dihydropteroate synthase) protein structure (downloaded from Protein Data Bank) to establish the most preferred mode of interaction. ADMET filtration, Cytotoxicity (MTT assay) and haemolysis assay have been examined for evaluation of druglike character. [ABSTRACT FROM AUTHOR]

Monsonia angustifolia is traditionally used to treat anthrax, heartburn, diarrhea, eye infections and hemorrhoids. Dodonaea angustifolia is frequently used as a treatment for dental pain, microbial infections and jungle fever. The two plant species were selected due to the presence of secondary metabolites such as coumarins, flavonoids, terpenoids, saponins and polyphenolics from the crude extracts, which exhibit pharmacological significance. The pure isolated compounds from the crude extracts are known for their diverse structures and interesting pharmacophores. To isolate and identify antibacterial and antifungal chemical constituents from Monsonia angustifolia and Dodonaea angustifolia plant extracts and evaluate the cytotoxicity of pure compounds from the crude extracts. Extractives from M. angustifolia and D. angustifolia plants were isolated using chromatographic techniques and structures were elucidated based on NMR, IR and MS spectroscopic techniques. A microplate serial dilution method was used to evaluate the antibacterial activity of extracts and pure compounds against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and antifungal activity against Candida albicans and Cryptococcus neoformans. The cytotoxicity was determined using the 3-(4, 5-dimethylthiazol)-2, 5-diphenyl tetrazolium bromide (MTT) assay. The dichloromethane, ethyl acetate and methanol crude extracts from the plants exhibited significant inhibition of microbial growth. The phytochemical investigation of these active crude extracts led to the isolation of five pure active compounds, 5-methoxyjusticidin A (1), cis -phytyl diterpenoidal fatty acid ester (2), stigmasterol (3), β -sitosterol (4) and 5-hydroxy-7,4′-dimethoxyflavone (5). Stigmasterol (3) showed good antifungal activity against Cryptococcus neoformans with a minimum inhibition concentration (MIC) of 25 μg/mL and Candida albicans (MIC = 50 μg/mL). Compounds (1 – 5) isolated from Monsonia angustifolia and Dodonaea angustifolia showed antibacterial and antifungal activities and were non-toxic against Madin-Darby canine kidney (MDCK) cells and VERO monkey kidney (VERO) cells. [Display omitted] ∙ Four compounds (1 , 2 , 3 and 4) were isolated from Monsonia angustifolia. ∙ Compound 5 was isolated from Dodonaea angustifolia. ∙ Compounds (1-5) were screened for antimicrobial activity and tested for cytotoxicity. ∙ All compounds were non-toxic to MDCK and VERO cells. [ABSTRACT FROM AUTHOR]

Croton kongensis Gagnepain. belongs to the genus Croton , the Euphorbiaceae family, mainly distributed in Hainan and southern Yunnan, China. The aim of present study was to acquire secondary metabolites of the ethanol extract obtained from the leaves and twigs of C. kongensis. Three new abietane-type diterpenoids, crokongenolides A-C (1 – 3), together with seven known diterpenoids (4 – 10), were isolated from the leaves and twigs of C. kongensis. The structures of the new compounds were determined by extensive spectroscopic methods (1D and 2D NMR, IR, and HRESIMS), and their absolute configurations were confirmed by single-crystal X-ray diffraction analysis or electronic circular dichroism (ECD) calculations. The absolute configuration of 4 was determined for the first time by single-crystal X-ray diffraction analysis with Cu-Kα irradiation. Some compounds were evaluated for their antimicrobial properties by assessing their inhibitory effects on Staphylococcus aureus , Candida albicans , and Escherichia coli. Compound 10 showed significant antimicrobial activity against S. aureus with MIC value of 1.56 μg/ml. [Display omitted] • Three new abietane-type diterpenoids were isolated from the leaves and twigs of Croton kongensis. • The structures of three new compounds were elucidated by extensive analysis of spectroscopic data. • Some compounds showed significant antimicrobial activity against Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

We report the synthesis of a novel Schiff base ( E )-3-[(3,5-bis(trifluoromethyl) phenylimino)methyl] benzene-1,2-diol from the reaction of 2,3-dihydroxybenzaldehyde with 3,5-bis(trifluoromethyl)aniline, and its Ni(II) and Cu(II) complexes. The molecular structure of the Schiff base was experimentally determined using X-ray single-crystal data and was compared to the structure predicted by theoretical calculations using density functional theory (DFT), Hartree-Fock (HF) and Möller–Plesset second-order perturbation (MP2). In addition, nonlinear optical (NLO) effects of the compound was predicted using DFT. The antimicrobial activities of the compounds were investigated for their minimum inhibitory concentration. UV–Vis spectroscopy studies of the interactions between the compounds and calf thymus DNA (CT-DNA) showed that the compounds interacts with CT-DNA via intercalative binding. A DNA cleavage study showed that the Cu(II) complex cleaved DNA without any external agents. The compounds inhibited the base pair mutation in the absence of S9 with high inhibition rate. In addition, in vitro cytotoxicity of the Ni(II) complex towards HepG2 cell line was assayed by the MTT method. Also, the colorimetric response of the Schiff base in DMSO to the addition of equivalent amount of anions (F − , Br − , I − , CN − , SCN − , ClO 4 − , HSO 4 − , AcO − , H 2 PO 4 − , N 3 − and OH − ) was investigated. In this regard, while the addition of F − , CN − , AcO − and OH − anions into the solution containing Schiff base resulted in a significant color change, the addition of Br − , I − , SCN − , ClO 4 − , HSO 4 − , H 2 PO 4 − and N 3 − anions resulted in no color change. The most discernable color change in the Schiff base was caused by CN − , which demonstrated that the ligand can be used to selectively detect CN − . [ABSTRACT FROM AUTHOR]

The synthesis of a novel phthalonitrile derivative with pyridine-2-thiol and 2,4,6-trimethylphenylamine substituents functionalized groups and its peripherally tetrasubstituted cobalt phthalocyanine and cationic phthalocyanines complexes were reported. The aggregation investigations carried out in different concentrations indicate that Co Phthalocyanines compounds 3 , 4 do not have any aggregation behavior for the concentration range of 6 × 10 − 4 –14 × 10 − 6 M in DMSO. The ion binding properties of Co Phthalocyanines compounds 3 , 4 show the formation of stable complex with Co 2 + . In addition 3,4-Dihydropyrimidin-2(1H)-one derivatives were synthesized by modified Biginelli cyclocondensation reaction catalyzed by MPc as Lewis base. The structures of the synthesized compounds have been successfully characterized by the spectroscopic methods (IR, 1 H NMR, 13C NMR, UV–Vis, mass spectrometry, elemental analysis and NMR 2D). The influence of substrate/catalyst ratio, solvent was also investigated to find optimal reaction on this synthesis for getting the highest conversion. Different parameters were examined for finding optimal conditions of catalysis. In addition; the compounds 3–11 were investigated for antimicrobial activity. Most of them exhibited important antimicrobial activity. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides offer a new class of therapeutic agents to which bacteria may not be able to develop genetic resistance, since their main activity is in the lipid component of the bacterial cell membrane. We have developed a series of synthetic cationic cyclic lipopeptides based on natural polymyxin, and in this work we explore the interaction of sp-85, an analog that contains a C12 fatty acid at the N-terminus and two residues of arginine. This analog has been selected from its broad spectrum antibacterial activity in the micromolar range, and it has a disruptive action on the cytoplasmic membrane of bacteria, as demonstrated by TEM. In order to obtain information on the interaction of this analog with membrane lipids, we have obtained thermodynamic parameters from mixed monolayers prepared with POPG and POPE/POPG (molar ratio 6:4), as models of Gram positive and Gram negative bacteria, respectively. Langmuir–Blodgett films have been extracted on glass plates and observed by confocal microscopy, and images are consistent with a strong destabilizing effect on the membrane organization induced by sp-85. The effect of sp-85 on the membrane is confirmed with unilamelar lipid vesicles of the same composition, where biophysical experiments based on fluorescence are indicative of membrane fusion and permeabilization starting at very low concentrations of peptide and only if anionic lipids are present. Overall, results described here provide strong evidence that the mode of action of sp-85 is the alteration of the bacterial membrane permeability barrier. [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]

The Study for Monitoring Antimicrobial Resistance Trends has monitored the in vitro activity of several recommended antimicrobials used in the management of intra-abdominal infections (IAIs) globally since 2002. In this report, we document the changing susceptibility patterns to recommended antimicrobials in Klebsiella pneumoniae isolates from patients with IAIs in 11 Latin American countries between 2008 and 2012 and describe the beta-lactamases encoded by phenotypically extended-spectrum beta-lactamase (ESBL)–positive and ertapenem-nonsusceptible isolates. Overall, the incidence of phenotypically ESBL-positive K. pneumoniae did not change significantly from 2008 (40.4%) to 2012 (41.2%) ( P > 0.05). However, trend analysis documented an increase in isolates encoding K. pneumoniae carbapenemase (KPC) or both KPC and an ESBL. Decreasing susceptibility ( P < 0.05) was noted for cefepime, ceftazidime, ceftriaxone, ertapenem, and imipenem among all K. pneumoniae , as well as for cefepime, cefotaxime, cefoxitin, ceftriaxone, ertapenem, and imipenem among ESBL-positive isolates, while susceptibility of ESBL-negative isolates to ampicillin-sulbactam actually increased ( P < 0.05). [ABSTRACT FROM AUTHOR]

A single crystal of 3,4-dihydroxybenzylidene isonicotinylhydrazone, HBINH, has been grown and solved by X-ray crystallography. The VO 2+ , Zr 4+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ , Hg 2+ and Pd 2+ complexes of HBINH have been prepared and spectroscopically characterized. The data confirmed the formulae [Co(HBINH)(H 2 O)Cl]Cl·H 2 O, [Pd(HBINH)Cl 2 ], [Zn(HBINH) 2 Cl 2 ], [Cd(HBINH)(H 2 O) 2 Cl 2 ]·1½H 2 O, [(VO) 2 (HBINH-3H)(OH)(H 2 O)], [Ni 2 (HBINH)(H 2 O) 6 Cl 2 ]Cl 2 , [Cu 2 (HBINH-3H)(H 2 O) 2 (OAc)]·3H 2 O, [Zr 2 (HBINH-3H)Cl 4 ]Cl, [Hg 2 (HBINH)Cl 4 ] and the dimer {[Cu(HBINH)Cl]Cl} 2 . Most of the complexes have intense colors and high melting points and some are electrolytes in DMSO solution. The ligand behaves as a neutral bidentate in the Co(II), Cu(II), Pd(II), Zn(II) and Cd(II) complexes; dibasic tetradentate in [Ni 2 (HBINH)(H 2 O) 6 Cl 2 ]Cl 2 and tribasic tetradentate in [Cu 2 (HBINH-3H)(OAc)]·5H 2 O, [(VO) 2 (HBINH-3H)(OH)(H 2 O)] and [Zr 2 (HBINH-3H)Cl 4 ]Cl by the loss of 3H + due to the deprotonation of the two hydroxyl groups and the enolization of the amide (O CNH) group. A tetrahedral geometry was proposed for the Co(II), Cu(II), Zn(II) and Hg(II) complexes; square-planar for the Pd(II) complex; square-pyramid for the VO 2+ complex and octahedral for the Ni(II) and Cd(II) complexes. The complexes [Cd(HBINH)(H 2 O) 2 Cl 2 ]·1½H 2 O, [(VO) 2 (HBINH-3H)(OH)(H 2 O)] and [Cu 2 (HBINH-3H)-(H 2 O) 2 (OAc)]·3H 2 O have activities against Bacillus sp. M3010, Candida albicans , Escherichia coli , Staphylococcus aureus and Slamonella sp. PA393. [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]

Silver complex of 4-Amino-N-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide (sulfamethoxazole) (SMX) has been synthesized and characterized by elemental analysis, infrared, UV and NMR spectroscopy. The title compound, [Ag 2 (C 10 H 10 N 3 O 3 S) 2 (C 5 H 5 N) 3 ] crystallizes in the orthorhombic space group Pna2 1 with lattice parameters a = 17.9527(5), b = 8.6529(3), c = 25.1621(7) Å and Z = 4. The structure is solved by direct method and refined to a final R = 0.0567 for 6732 reflections with I ⩾ 2 σ ( I ). The results of IR, 1 H NMR and 13 C NMR spectral data suggest the binding of silver atom to the sulfonamide ligand which is in agreement with the crystal structure determination. X-ray analysis revealed that in the title compound, one silver atom is surrounded by three N atoms and one Ag atom leading to a distorted tetrahedral geometry and another silver atom is surrounded by four N atoms and one Ag atom leading to a slightly distorted square pyramid geometry with Ag⋯Ag separation distance of 3.026 Å. The dihedral angle between phenyl and isoxazole ring is 85.7(4)°. In the crystal structure, the molecules are linked via N H⋯O, C H⋯O intermolecular and C H⋯O intramolecular interactions. Silver complex of sulfamethoxazole has been studied by electrical and thermal analysis. Silver sulfamethoxazole presents different antibacterial behavior against Escherichia coli and Staphylococcus aureus strains. [ABSTRACT FROM AUTHOR]

In the present study, we have adapted a facile and efficient green route for the synthesis of HAP nanoparticles using pectin as a template which was extracted from the peel of prickly pear ( Opuntia ficus indica ) fruits. The concentration of pectin plays a major role in the behavior of crystallinity, purity, morphology as well as biological property of the as-synthesized HAP nanoparticles. The extracted pectin and the as-synthesized nanoparticles were characterized by various analytical techniques. The in vitro apatite formation on the surface of the as-synthesized nanoparticles in simulated body fluid (SBF) for various days showed an enhanced bioactivity. Also, the antimicrobial activity was investigated using various microorganisms. All the results revealed the formation of pure, low crystalline and discrete granular like HAP nanoparticles of size around 25 nm with enhanced biological and antimicrobial activities. Hence the as-synthesized nanoparticles can act as a better bone regenerating material in the field of biomedicine. [ABSTRACT FROM AUTHOR]

An orange colored pyrrole dihydrazone: Pyrrole-2,5-dicarboxaldehyde bis(oxaloyldihydrazone) (PDBO) has been synthesized by reaction of oxalic acid dihydrazide with 2,5 diformyl-1 H -pyrrole and has been characterized by spectroscopic analysis ( 1 H, 13 C NMR, UV–visible, FT-IR and DART Mass). The properties of the compound has been evaluated using B3LYP functional and 6-31G(d,p)/6-311+G(d,p) basis set. The symmetric (3319, 3320 cm −1 ) and asymmetric (3389, 3382 cm −1 ) stretching wave number confirm free NH 2 groups in PDBO. NBO analysis shows, inter/intra molecular interactions within the molecule. Topological parameters have been analyzed by QTAIM theory and provide the existence of intramolecular hydrogen bonding (N–H⋯O). The local reactivity descriptors analyses determine the reactive sites within molecule. The calculated first hyperpolarizability value ( β 0 = 23.83 × 10 −30 esu) of pyrrole dihydrazone shows its suitability for non-linear optical (NLO) response. The preliminary bioassay suggested that the PDBO exhibits relatively good antibacterial and fungicidal activity against Escherichia coli , Pseudomonas aeruginosa , Staphylococcus aureus , Streptococcus pyogenes , Candida albicans , Aspergillus niger . The local reactivity descriptors – Fukui functions ( f k + , f k − ), local softnesses ( s k + , s k − ) and electrophilicity indices ( ω k + , ω k − ) analyses have been used to determine the reactive sites within molecule. [ABSTRACT FROM AUTHOR]

A new pentafunctional N 3 O 2 Schiff base, H 2 L ligand, and its metal chelates with Cu(II), Ni(II), Co(II), VO(IV), Zn(II), Cd(II), Ce(III), Cr(III), Fe(III) and UO 2 (VI) have been synthesized and characterized by elemental analysis, spectral, molar conductance, magnetic and thermal gravimetric studies. The results showed that the complexes have octahedral geometry except UO 2 complex which has pentagonal bipyramidal arrangement. The TGA analyses suggest high stability for most complexes followed by thermal decomposition in different steps. The kinetic and thermodynamic parameters for decomposition steps of metal complexes thermograms have been calculated. Molecular orbital calculations were performed for the ligand and its metal complexes by means of hyperchem 7.52 program on the bases of semiempirical PM3 level and the results were correlated with the experimental data. The antimicrobial activity of the synthesized compounds were tested in vitro against some Gram-positive and Gram-negative bacteria; yeast and fungus strains and the results were discussed in terms of extended Lewis acid–base interactions. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) has immense potential applications in water purification and biomedical field. Recently, three-dimensional GO-based hydrogels have attracted great attention owing to their advantageous properties. However, it is quite difficult to develop highly efficient, low cost, broad spectrum antibacterial materials that can be easily recycled. In this experimental work, we used a facile one-pot method to synthesize two kinds of GO-based hydrogels: benzalkonium bromide/graphene oxide hydrogel (BKB/GOG) and benzalkonium bromide/polydopamine/reduced graphene oxide hydrogel (BKB/PDA/rGOG). The as-prepared three-dimensional hydrogels were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. The swelling degrees of BKB/GO xerogels and BKB/PDA/GO xerogels with different BKB concentrations were calculated. The maximum value of swelling degree was found to be 95.2 mg/mg. Owing to the synergistic effect of graphene oxide and benzalkonium bromide, the resultant hydrogels exhibited strong antibacterial activities against both Gram-negative and Gram-positive bacteria. The result of bacterial kinetic tests agreed well with that of the qualitative antibacterial experiments. The resultant hydrogels could be easily removed from the solution, which enhanced their potential use in industrial applications. The antibacterial effect of the hydrogel synthesized from benzalkonium chloride (BKC) and graphene oxide was investigated. The findings of this investigation can be beneficial in elucidating the mechanism of synthesis process that involves benzalkonium salts and graphene oxide. [ABSTRACT FROM AUTHOR]

Two altenuene derivatives ( 1 – 2 ) and one isocoumarin ( 3 ), together with six known compounds ( 4 – 9 ) were isolated from solid cultures of an endophytic fungus Alternaria alternata , obtained from the fresh branches of Camellia sinensis . Chiral analysis revealed the racemic nature of 1 and 2 , which were subsequently resolved into two pairs of enantiomers [(+)- 1 and (−)- 1 , (+)- 2 and (−)- 2 ]. Structures of all the isolates were identified through spectroscopic data. Absolute configurations of the two pairs of enantiomers were determined by electronic circular dichroism (ECD) calculation and the chiral center of C-10 in 3 was deduced via [Rh 2 (OCOCF 3 ) 4 ]-induced CD experiment. All the isolates were evaluated for their antimicrobial abilities against the pathogenic bacteria and fungi as well as cytotoxic activities against two human tumor cell lines. Compound 5 was the most active against Bacillus subtilis with MIC 80 of 8.6 μ g/ml, and compounds 1 – 3 , 6 – 7 and 9 exhibited moderate to weak inhibition towards the test pathogenic microorganism. Compound 4 showed mild cytotoxic activity against human osteosarcoma cells U2OS with IC 50 of 28.3 μ M. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of the acetone extract from the immature fruits of Garcinia cowa led to the isolation of two novel tetraoxygenated xanthones, garcicowanones A ( 1 ) and B ( 2 ), together with eight known tetraoxygeanted xanthones. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their antibacterial activity against Bacillus cereus TISTR 688, Bacillus subtilis TISTR 008, Micrococcus luteus TISTR 884, Staphylococcus aureus TISTR 1466, Escherichia coli TISTR 780, Pseudomonas aeruginosa TISTR 781, Salmonella typhimurium TISTR 292 and Staphylococcus epidermidis ATCC 12228. α-Mangostin showed potent activity (MIC 0.25–1 μg/mL) against three Gram–positive strains and garcicowanone A and β-mangostin exhibited strong antibacterial activity against B. cereus with the same MIC values of 0.25 μg/mL. [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]

Three new 2-(2-phenylethyl)chromone derivatives ( 1 – 3 ), together with thirteen known ones ( 4 – 16 ), were isolated from the EtOAc extract of Chinese agarwood induced by artificial holing, originating from Aquilaria sinensis (Lour.) Gilg (Thymelaeaceae). The chemical structures of the new compounds were identified by spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). Compounds 1 , 6 , 15 and 16 exhibited inhibitory effects on Staphylococcus aureus , and compounds 15 and 16 showed inhibitory effects on Ralstonia solanacearum . Compounds 1 – 3 , 7 , 9 , 11 , 12 , 15 and 16 exhibited acetylcholinesterase inhibitory activity. A possible biogenetic pathway of compounds 1 – 16 was proposed to show the relationships between diepoxy-tetrahydro-2-(2-phenylethyl)chromones, epoxy-tetrahydro-2-(2-phenylethyl) chromones, tetrahydro-2-(2-phenylethyl)chromones, and 2-(2-phenylethyl)chromones of the flidersia type, the four main types of 2-(2-phenylethyl)chromones found in agarwood, on the basis of their appearances in different stage of agarwood formation. [ABSTRACT FROM AUTHOR]

Highlights: [•] New bisiminated water insoluble azo–azomethine dyes have synthesized. [•] Solvatochromic properties of the dyes in various organic solvents have been investigated. [•] Aantimicrobial activities of the prepared dyes have been reported. [ABSTRACT FROM AUTHOR]

Highlights: [•] AuNP was synthesized using pomegranate extract – reducing and stabilizing agent. [•] Stability of AuNP confirmed by UV–Vis and HRTEM analyses after one month. [•] HRTEM images showed the spherical and triangular AuNP as small as 0.9nm. [•] AuNP showed excellent antimicrobial against various microorganisms and cytotoxic activities. [Copyright &y& Elsevier]

Tabernaemontana corymbosa is a traditional folk medicine. In our research, six monoterpene indole N -oxide alkaloids and their parent alkaloids were obtained from the stem bark of T. corymbosa , including seven new alkaloids (1 – 7) and five known alkaloids (8 – 12). Their structures and absolute configurations were elucidated by extensive spectroscopy, quantum chemical calculations, and DP4+ probability analyses. The antimicrobial activity of the obtained compounds was evaluated, among which alkaloids 4 , 8 , 12 showed significant antimicrobial activity against Staphylococcus aureus with an MIC value of 6.25 μ g/mL, while alkaloids 11 , 12 showed moderate antimicrobial activity against Bacillus subtilis with an MIC value of 25 μ g/mL. [Display omitted] • Six N -oxide MIAs and their parent alkaloids were isolated from T. corymbosa. • Compounds 1 – 7 were identified to be new MIAs. • Alkaloid 1 was determined by quantum chemical calculations, and DP4+ analysis. • The antimicrobial activity of all MIAs was evaluated and discussed their differences. [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]

Three new flavonoids, ephedroside A (1), ephedroside B (2), ephedroside C (3), together with fifty-four known compounds 4 – 57 were isolated from the EtOH extract of the herbaceous stems of Ephedra sinica. The structures of these compounds were elucidated by spectroscopic techniques, as well as by comparison with literature data. Thirty-eight of these compounds were isolated from the genus Ephedra for the first time. The antimicrobial activities of eight compounds were tested by measuring the minimum inhibitory concentrations (MIC) against bacteria (both Gram positive and Gram negative) and fungi, and were found to be in the range of 0.105–0.926 mM. Among them, compound 2 showed the best antimicrobial activity against Pseudomonas aeruginosa with MIC value of 0.105 mM. [Display omitted] [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]

A phytochemical investigation on the MeOH extract of the red alga Laurencia composita Yamada led to the discovery of six new highly halogenated sesquiterpenoids, including two bisabolane-type sesquiterpenoids (1 and 2), one nerolidol derivative (7), and three chamigrane-type sesquiterpenoids (9 , 10 , and 18), together with 13 known sesquiterpenoids. Their structures, including relative configuration, were elucidated by extensive spectroscopic analysis, and by comparison with data for related known compounds. The absolute configuration at C-10 of laurecomposin A (1) was determined by the modified Mosher's method. Halonerolidol (7) is the first naturally occurring halogenated nerolidol derivative, while compositacin L (9) represents the third example of chamigranes having a C-10 carbonyl group. Antifungal, antibacterial, and receptor tyrosine kinase inhibitory activities of these isolates were evaluated. The results showed that compounds 1–3 and 5 exhibited significant antifungal activity against Microsporum gypseum (Cmccfmza) with MIC values of 4, 8, 8, and 4 μg/mL, respectively. Additionally, compounds 1–3 and 5 also displayed promising antibacterial activity against Gram-positive bacteria Staphylococcus aureus Newman strain with MIC values ranging from 10.9 to 26.8 μg/mL. Unlabelled Image • Six new halosesquiterpenoids were isolated from Laurencia composita. • Halonerolidol is the first naturally occurring halogenated nerolidol derivative. • Four halosesquiterpenoids exhibited significant antifungal activity against Microsporum gypseum. • Four halosesquiterpenoids displayed promising antibacterial activity towards Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Five new abietane diterpenes, lophachinins A–E (1 – 5), and eleven known related diterpenes were isolated from a Mongolian traditional herbal medicine, the aerial parts of Lophanthus chinensis (Lamiaceae). The structures of new diterpenes were assigned by spectroscopic analyses. Lophachinins A (1) and B (2) were abietane diterpene possessing an endoperoxy bridge at C-ring. In contrast, lophachinins C–E (3 – 5) had an abietane skeleton with an aromatized C-ring. The absolute configuration of 1 was elucidated by application of the modified Mosher's method, while those of 2 , 3 , and 5 were assigned by chemical conversions. The absolute configuration of lophachinin D (4) was deduced by ECD calculation. Anti-inflammatory activity of isolated diterpenes on microglial cells were evaluated. Unlabelled Image [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]

Six new compounds [ascherlactones A (1) and B (2), ascherchromanone A (3), phenethyl 4′- O -methylglucoside (8), 4′- O -methylpleoside (10), and 4′- O -methyltorachrysone 8- O -glucoside (11)] and one naturally new compound [4′- O -methyl-β- d -benzylglucoside (9)] together with fourteen known compounds, including paecilodepsipeptides A (5), B (7), and D (4), conoideocrellide A (6), eugenin (12), 5-hydroxy-2,3-dimethyl-7-methoxychromone (13), (S)-1-phenyl-1,2-ethanediol (14), (2 S)- l -3-phenyllactic acid (15), papuline [or (2 S)- l -3-phenyllactic acid methyl ester, 16 , 2′- epi terpendole A (17), terpendoles C (18) and D (19), cholic acid, and zeorin were isolated from the entomopathogenic fungus Aschersonia confluens BCC53152. Their chemical structures were elucidated on the basis of NMR spectroscopic and mass spectrometric analyses. The absolute configurations were determined by using the evidence from NOESY correlations, chemical means, optical rotation values together with comparison of ECD spectroscopic data with the calculated ECD spectra. The plausible biosynthetic pathway of compounds 1 – 3 was also proposed. Moreover, antimicrobial activity such as antimalarial, antitubercular, antifungal, and antibacterial activities and cytotoxicity against cancerous (MCF-7, KB, and NCI-H187) and non-cancerous (Vero) cells of the isolated compounds were evaluated. Unlabelled Image [ABSTRACT FROM AUTHOR]

Four new sesquiterpenoids, conyterpenols A − D (1 – 4), along with nineteen known analogues (5 – 23) were isolated from the aerial parts of Conyza japonica. The structures of 1 – 4 were determined through spectroscopic analysis, while their absolute configurations were determined by comparison of calculated and experimental electronic circular dichroism (ECD) spectra. Conyterpenol D (4) was a new type of sesquiterpenoid with a seven-membered lactone ring. Compounds 1 – 23 were evaluated for their inhibitory activity against LPS-induced nitric oxide production in RAW264.7 macrophages and cytotoxicity against human hepatoma cell line (HepG2) and human breast adenocarcinoma cell line (MCF-7). Compounds 3 , 4 , and 12 displayed moderate inhibition against NO production with IC 50 values in the range of 26.4–33.6 μM. And all compounds showed no obvious cytotoxicity against these two cancer cell lines at 100 μM. Unlabelled Image • Four new sesquiterpenoids were isolated from the aerial parts of Conyza japonica (Thunb.) Less. • A new type of sesquiterpenoid with seven-membered lactone ring and benzene ring. • Structure of new compounds were elucidated through various spectroscopic analysis. • The inhibitory activity of isolated compounds against LPS-induced NO production in RAW264.7 macrophages was evaluated. [ABSTRACT FROM AUTHOR]

A new alkaloid, named (±)-preisomide (1), together with five known polyketides (2 – 6), were isolated from an endophytic fungus Preussia isomera in Panax notoginseng by using one strain-many compounds (OSMAC) strategy. Their structures were identified by extensive spectroscopic experiments and comparison with literature data. Structurally, compound 1 possessed a rare naturally occurring tetrahydro-2 H -1,2-oxazin ring. Compound 6 displayed significant antibacterial activity against multidrug-resistant Enterococcus faecium , methicinllin-resistant Staphylococcus aureus and multidrug-resistant Enterococcus faecalis with an MIC value of 25 μg/mL, as well as moderate antifungal activity against Gibberella saubinetii with an MIC value of 50 μg/mL. Unlabelled Image [ABSTRACT FROM AUTHOR]

Fourteen new compounds including thirteen drimane – phthalide derivatives (fendlerals A – C, fendlerins A – D, fendlerols A – B, fendleric acids A – C, fendlerinine G) and one terphenyl derivative (fendleryl E) along with eight known compounds, fendlerinine A, rickenyls C – D, fendleryls C – D, atromentin, tetramethyl atromentin, and (±)-microsphaerophthalide F, were isolated from the wood fungus Hypoxylon fendleri BCC32408. Compared with the prior work, the results indicated the agitation effect on the production of bioactive drimane – phthalides. The chemical structures were determined based upon spectroscopic analyses and the absolute configurations were verified by comparison of the ECD spectral data with the calculated ECD spectra of the related compounds. Compounds 1–3 exhibited antimicrobial activity against Plasmodium falciparum (IC 50 4.15–4.39 μM), Colletotrichum capsici (MIC 6.25–12.5 μg/mL), and Bacillus cereus (MIC 1.56–3.13 μg/mL). All tested compounds displayed broad cytotoxicity against cancerous (MCF-7, KB, and NCI-H187) and non-cancerous (Vero) cells. Unlabelled Image [ABSTRACT FROM AUTHOR]