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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]

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 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]

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]

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]

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]

Abstract: A phytochemical investigation on the stems of Anodendron formicinum led to the isolation of eight prenylbenzoic acid derivatives. Three of these were new compounds, designated as formicinuosides A (1), B (2), and C (3). Their structures were elucidated on the basis of extensive spectroscopic analysis, as well as by comparison with the reported spectroscopic data. This is the first report of chemical constituents from A. formicinum and their antimicrobial activities. Among the isolated compounds, compounds 4, 6 and 8 showed significant antibacterial activities against Providensia smartii with MIC values of 0.781μg/mL. Moreover, compound 8 showed remarkable antibacterial activity against Escherichia coli with MIC value of 0.781μg/mL. [Copyright &y& Elsevier]

Abstract: Phytochemical and antimicrobial activity study on the ethanol extract of the leaves and stems of Loropetalum chinense led to the isolation of a new flavan-3-ol compounds, 8-[1-(3,4-dihydroxyphenyl)-3-methoxy-3-oxopropyl]-catechin (loropetaliside A) (1) and a new lignan glucoside, 1-(5-hydroxy-3-methoxyphenyl)-2-(2-β-glucopyranosyl-4-hydroxy-5-(1-(E)propen-3-ol)-phenyl)-propane-3-ol (loropetaliside B) (3) and several known compounds manglieside D (2), quercetin (4), kaempferol-3-O-D-glucopyranoside (5), quercetin-3-O-β-L-rhamnoside (6) and tiliroside (7). Their structures were elucidated on the basis of extensive spectroscopic analysis. [Copyright &y& Elsevier]

Abstract: Further phytochemical investigation on the stems and leaves of Paris polyphylla var. yunnanensis has led to the isolation of three C22-steroidal lactone glycosides. Two of these are new compounds, designated as chonglouoside SL-7 (1) and chonglouoside SL-8 (2). Their structures were elucidated on the basis of extensive spectroscopic analysis, as well as comparison with the reported spectroscopic data. This is the first report of C22-steroidal lactone glycosides isolated from the Paris genus. Compounds 1 and 3 showed moderate antimicrobic activity against Propionibacterium acnes with MIC values of 31.3 and 3.9μg/mL, respectively. [Copyright &y& Elsevier]

Abstract: A deoxy lupane triterpene carboxylic acid, lup-20(29)-en-24-oic acid (1), was isolated from the active chloroform extract of Finlaysonia obovata, a latex exuding mangrove plant. Its structure was evaluated on the basis of different spectroscopic methods, including extensive 1D and 2D NMR spectroscopy. Lup-20(29)-en-24-oic acid (1) has shown moderate antimicrobial activity, against some fish pathogens. [Copyright &y& Elsevier]

Abstract: Three new humulane-type sesquiterpenes, 8-O-(p-coumaroyl)-5β-hydroperoxy-1(10)E,4(15)-humuladien-8α-ol (1), 8-O-(3-nitro-p-coumaroyl)-1(10)E,4(15)-humuladien-5β,8α-diol (2) and 8-O-(p-coumaroyl)-1(10)E,4(5)E-humuladien-8-ol (3), and a new copaborneol derivative, 1-O-p-coumaroyl-copaborneol (4), have been isolated from the methanol extract of Pilea cavaleriei Lévl. subsp. crenata C. J. Chen. Their structures were elucidated using spectroscopic methods. Cytotoxic and antimicrobial activities of the isolated compounds were evaluated. [Copyright &y& Elsevier]

Abstract: The nor-halimane diterpenoid tessmannic acid and its methyl, 2-methylisopropyl and 1-methylbutyl esters, the unusual isocoumarins 8-hydroxy-6-methoxy-3-pentylisocoumarin and 7-chloro-8-hydroxy-6-methoxy-3-pentylisocoumarin, and 5-pentyl-3-methoxy-N-butylaniline were isolated from the stem and root bark extracts of Tessmannia densiflora Harms (Caesalpiniaceae) that showed mosquito larvicidal activity. The structures were determined on interpretation of spectroscopic data. Tessmannic acid and its methyl ester exhibited antibacterial and antifungal activity. The compounds also caused high larvae and adult Anopheles gambiae mosquitoe mortality effects, and stronger mosquito repellency than that shown by the standard repellent DEET, hence indicating Tessmannia species to be potential sources of bioactive natural products. [Copyright &y& Elsevier]

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]

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]