Two New Oleanane-Triterpenoid Saponins from Clinopodium gracile

Two new oleanane-triterpenoid saponins, clinograsaponins A ( 1 ) and B ( 2 ), together with twelve known ones ( 3 – 14 ), were isolated from the whole herb of Clinopodium gracile (Bentham) Matsumura. Their structures were determined by spectroscopic analysis and chemical method. All the isolated compounds were evaluated for their activities against ATP-citrate lyase (ACLY) and nuclear factor kappa B (NF-κB).     

Chemical Constituents of the Branches and Leaves of Picrasma chinensis P.Y. Chen and Tyrosinase Inhibiting Activity

One new alkaloid, picrasine A, two new quassinoids, picralactones A−B, together with eleven known compounds were isolated from Picrasma chinensis P.Y. Chen. The structures of these compounds were determined using 1D and 2D NMR, HR-ESI-MS, and IR spectroscopic data, and by comparison with published data. Some compounds were tested for tyrosinase inhibiting activity, however, none of them exhibited strong inhibitory effects.     

Secondary Metabolites from Aspergillus fumigatus,an Endophytic Fungus from the Liverwort Heteroscyphus tener (Steph.) Schiffn.

Three new metabolites, asperfumigatin ( 1 ), isochaetominine ( 10 ), and 8′‐O‐methylasterric acid ( 21 ), together with nineteen known compounds, were obtained from the culture of Aspergillus fumigatus, an endophytic fungus from the Chinese liverwort Heteroscyphus tener (Steph.) Schiffn. Their structures were established by extensive analysis of the spectroscopic data. The absolute configurations of 1 and 10 were determined by analysis of their respective CD spectra. Cytotoxicity of these isolates against four human cancer cell lines was also determined.     

Two Phenolic Compounds from Valsa ambiens

Two phenolic compounds were isolated from a filtrate of Valsa ambiensis. Their structures were determined to be a new compound (1) and scytalone (2) by spectroscopic methods. Both had an inhibitory effect on the growth of lettuce roots and hypocotyls.     

Cytotoxic ent-kaurane diterpenoids from Isodon sinuolata

Five (1–5) ent-kaurane diterpenoids and 17 other known ones, were isolated from the leaves and stems of Isodon sinuolata. Their structures were determined on the basis of spectroscopic methods including 1D and 2D NMR spectroscopic analysis. All compounds were evaluated for cytotoxicity against a small panel of cell lines. Some compounds exhibited significant cytotoxicity.     

New Guaiane-Type Sesquiterpene and Norsesquiterpene from Alisma plantago-aquatica and Their Xanthine Oxidase Inhibitory Activity

A new sesquiterpene ( 1 ) and a new norsesquiterpene ( 2 ) belonging guaiane-type skeleton together with six known compounds ( 3 – 8 ) were isolated from the rhizomes of Alisma plantago-aquatica. Their structures were determined by HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Absolute configurations of new compounds were established by experimental and TD-DFT computational ECD spectra. Compounds 1 – 8 exhibited xanthine oxidase inhibitory activity with their IC₅₀ values in range of 9.4–66.7 μM. The sesquiterpenoids 1 – 5 displayed the inhibitory activity and hence they could be potential xanthine oxidase inhibitors from A. plantago-aquatica.     

Netamines O–S,Five New Tricyclic Guanidine Alkaloids from the Madagascar Sponge Biemna laboutei,and Their Antimalarial Activities

In our continuing program to isolate new compounds from the Madagascar sponge Biemna laboutei, five new tricyclic guanidine alkaloids, netamines O – S ( 1 – 5 , resp.), have been identified together with the known compounds netamine E ( 6 ) and mirabilin J ( 7 ). The structures of all new netamines were assigned on the basis of spectroscopic analyses. Their relative configurations were established by analysis of ROESY data and comparison with literature data. Netamines O, P, and Q, which were isolated in sufficient quantities, were tested for their cytotoxic activities against KB cells and their activities against the malaria parasite Plasmodium falciparum. Netamines O and Q were found to be moderately cytotoxic. Netamines O, P, and Q exhibited antiplasmodial activities with IC₅₀ values of 16.99±4.12, 32.62±3.44, and 8.37±1.35 μM , respectively.     

Ganoderic acid derivatives and ergosta-4,7,22-triene-3,6-dione from Ganoderma lucidum

Seven new triterpenoids, ganoderic acid T, ganoderic acid S, ganoderic acid R, ganoderic acid P, ganoderic acid Q, ganoderic acid 0, 7-O-methyl-ganoderic acid 0 and a known ergosterol derivative, ergosta-4,7,22-triene-3,6-dione were isolated from the cultured mycelium of Ganoderma lucidum. The structure of the first compound was determined using spectroscopic and X-ray analysis, and the structures of the other compounds were elucidated by spectroscopic data.     

Two New Phenol Derivatives from the Cold Seep-Derived Fungus Aspergillus insuetus SD-512

Two new phenol derivatives, namely insphenol A ( 1 ) and acetylpeniciphenol ( 2 ), along with seven known analogs ( 3 – 9 ), were isolated from the deep-sea cold seep-derived fungus, Aspergillus insuetus SD-512. The structures of 1 and 2 were established by extensive interpretation of NMR and mass spectroscopic data. The absolute configuration of 1 was determined by the combination of coupling constant analysis and acid hydrolysis. Among the isolated compounds, insphenol A ( 1 ) represents the first example of isopentenyl phenol derivative with a unique 1-glycosylation from the species Aspergillus insuetus. The isolated new compounds were evaluated for antibacterial activities against six human or aquatic pathogens, while compound 2 exhibited inhibitory effect against Edwardsiella tarda, Vibrio alginolyticus, and V. vulnificus, with MIC values of 4, 8, and 8 μg/mL, respectively.     

New Derivatives of Nonactic and Homononactic Acids from Bacillus pumilus Derived from Breynia fruticosa

Six new nonactic and homononactic acid derivatives, ethyl homononactate ( 1 ), ethyl nonactate ( 2 ), homononactyl homononactate ( 6 ), ethyl homononactyl nonactate ( 7 ), ethyl homononactyl homononactate ( 8 ), and ethyl nonactyl nonactate ( 9 ), as well as four known compounds, homononactic acid ( 3 ), nonactic acid ( 4 ), homononactyl nonactate ( 5 ), and bishomononactic acid ( 10 ), were isolated from culture broth of Bacillus pumilus derived from Breynia fruticosa. The structures of new compounds were elucidated by spectroscopic analysis and chemical methods. The optical purities of 1 – 6 were determined by HPLC/MS after treatment with L ‐phenylalanine methyl ester. The dimeric compounds 5 – 9 showed weak cytotoxic activities against five human cancer cell lines (IC₅₀ 19–100 μg/ml).     

Three New Hydroxyphenylacetic Acid Derivatives and A New Alkaloid from Endophytic Fungus Mortierella sp. in Epimedium acuminatum Franch. and Their Antibacterial Activity

Three new hydroxyphenylacetic acid derivatives, stachylines E-G ( 1 – 3 ), and a new alkaloid, mortieridinone ( 4 ), along with six known compounds ( 5 – 10 ), were isolated from endophytic fungus Mortierella sp. in Epimedium acuminatum Franch. Their structures were determined by their spectroscopic analyses and by comparison with the literature data. Compounds 7 and 10 showed selective antibacterial activity against tested multidrug-resistant bacteria with minimum inhibitory concentration (MIC) values ranging from 25 to 3.13 μg/mL.     

Aspergetherins A-D,New Chlorinated Biphenyls with anti-MRSA Activity from the Marine Sponge Symbiotic Fungus Aspergillus terreus 164018

Aspergetherins A-D ( 1 – 4 ), four new chlorinated biphenyls, were isolated from the rice fermentation of a marine sponge symbiotic fungus Aspergillus terreus 164018, along with seven known biphenyl derivatives ( 5 – 11 ). The structures of four new compounds were determined by a comprehensive analysis of the spectroscopic data, including HR-ESI-MS and 2D NMR data. All 11 isolates were evaluated for their anti-bacterial activity against two strains of methicillin-resistant Staphylococcus aureus (MRSA). Among them, compounds 1 , 3 , 8 and 10 showed anti-MRSA activity with MIC values of 1.0–128 μg/mL. Preliminary structure-activity relationship analysis unveiled that both chlorinated substitution and esterification of 2-carboxylic acid could impact the antibacterial activity of biphenyls.     

Bioactive Pimarane Diterpenes from the Arctic Fungus Eutypella sp. D‐1

Two new pimarane diterpenes, libertellenone M ( 1 ) and libertellenone N ( 2 ), together with five known compounds were isolated from the culture extract of Eutypella sp. D‐1 derived from high‐latitude soil of the Arctic. The structures of these compounds were determined by spectroscopic data as well as experimental and calculated electronic circular dichroism (ECD) analysis. Antimicrobial and cytotoxic activities of the isolated compounds were evaluated. Compound 3 exhibited weak antibacterial activity against Escherichia coli, Bacillus subtilis, and Vibrio vulnificus, each with MIC values of 16 μg/mL. Compounds 2 and 3 showed moderate cytotoxic activity against K562 and MCF‐7 cell lines with IC₅₀ values of 7.67 and 9.57 μm , respectively.     

Two New Avermectin Derivatives from the Beibu Gulf Gorgonian Anthogorgia caerulea

Two new avermectin derivatives, avermectins B_1c and B_1e ( 1 and 2 , resp.), as well as two known compounds, avermectin B_2a ( 3 ) and ivermectin A_1a ( 4 ), were isolated from a Beibu Gulf gorgonian coral, Anthogorgia caerulea. The structures of the new compounds were established by detailed spectroscopic analysis and by comparison with spectral data of related known compounds. Compounds 1 – 4 showed moderate antifouling activities against the larval settlement of Balanus amphitrite.     

Two New Prenylated Indole Diterpenoids from Tolypocladium sp. and Their Antimicrobial Activities

Two new prenylated indole diterpenoids, tolypocladins K and L ( 1 and 2 ), together with a known analog terpendole L ( 3 ), were isolated from the solid fermentation culture of a mine soil‐derived fungus Tolypocladium sp. XL115. Their structures and relative configurations were determined by comprehensive spectroscopic data analysis, as well as by comparison of their NMR data with those related known compounds. Compound 3 exhibited remarkable antibacterial activity against Micrococcus luteus with an MIC value of 6.25 μg/mL, and compounds 1 and 3 displayed moderate antifungal activity selectively against tested strains with MIC values of 25–50 μg/mL.     

Diterpenes from the Roots of Oryza sativa L. and Their Inhibition Activity on NO Production in LPS‐Stimulated RAW264.7 Macrophages

Two new pimarane diterpenoids, momilactone D ( 3 ) and momilactone E ( 5 ), along with three known diterpenoids, momilactone A ( 1 ), sandaracopimaradien‐3‐one ( 2 ), and oryzalexin A ( 4 ) were isolated from Oryza sativa roots. The chemical structures of the compounds were determined by spectroscopic data analysis. The isolated diterpenoids were evaluated for their ability to inhibit NO production and iNOS mRNA and protein expression in LPS‐stimulated RAW264.7 macrophages. Compound 4 showed strong inhibition activity on NO production, and compounds 1 and 4 decreased the expression of iNOS mRNA and protein levels.     

New phenylspirodrimane metabolites MBJ-0030, MBJ-0031, and MBJ-0032 isolated from the soil fungal strain Stachybotrys sp. f23793

ABSTRACT

Chemical screening of culture medium from the soil fungus Stachybotrys sp. resulted in the isolation of the three new phenylspirodrimanes MBJ-0030 (1), MBJ-0031 (2) and MBJ-0032 (3). Their structures were determined by detailed analysis of spectroscopic data. The absolute configurations of 1–3 were determined by modified Mosher’s and Marfey’s methods. In addition, cytotoxic and antimicrobial evaluations of the compounds were conducted.     

Structural and Stereochemical Studies of Hydroxyanthraquinone Derivatives from the Endophytic Fungus Coniothyrium sp

Four known hydroxyanthraquinones ( 1–4 ) together with four new derivatives having a tetralone moiety, namely coniothyrinones A–D ( 5–8 ), were isolated from the culture of Coniothyrium sp., an endophytic fungus isolated from Salsola oppostifolia from Gomera in the Canary Islands. The structures of the new compounds were elucidated by detailed spectroscopic analysis and comparison with reported data. The absolute configurations of coniothyrinones A ( 5 ), B ( 6 ), and D ( 8 ) were determined by TDDFT calculations of CD spectra, allowing the determination of the absolute configuration of coniothyrinone C ( 7 ) as well. Coniothyrinones A ( 5 ), B ( 6 ), and D ( 8 ) could be used as ECD reference compounds in the determination of absolute configuration for related tetralone derivatives. This is the first report of anthraquinones and derivatives from an isolate of the genus Coniothyrium sp. These compounds showed inhibitory effects against the fungus Microbotryum violaceum, the alga Chlorella fusca, and the bacteria Escherichia coli and Bacillus megaterium. Chirality 25:141–148, 2013. © 2012 Wiley Periodicals, Inc.     

Drimane Sesquiterpenoids from the Aspergillus oryzae QXPC‐4

Three new drimane sesquiterpenoids, astellolides C–E ( 1 – 3 , resp.), four new drimane sesquiterpenoid p‐hydroxybenzoates, astellolides F–I ( 4 – 7 , resp.), together with two known compounds astellolides A and B ( 8 and 9 , resp.), have been isolated from the liquid culture of Aspergillus oryzae (strain No. QXPC‐4). Their structures were established by comprehensive analysis of spectroscopic data. The relative and absolute configurations were determined on the basis of NOESY and CD data, together with single‐crystal X‐ray diffraction analyses of compounds 1 – 3 . The metabolites were evaluated for their cytotoxic activities, however, no compounds showed a significant cytotoxicity against the tested cell lines at a concentration of 20 μM .     

Three New Cembranoids from a Xisha Soft Coral Sarcophyton sp.

Chemical investigation of the Xisha soft coral Sarcophyton sp. has led to the isolation of eight cembrane-type diterpenoids, including three new compounds, namely sarcophynoids A-C ( 1 – 3 ), and five known analog compounds ( 4 – 8 ). Their structures were clarified based on spectroscopic analysis, and computer-assisted methods including TDDFT-ECD calculation and the quantum mechanical-nuclear magnetic resonance (QM-NMR) method. All the above compounds were tested for their antibacterial activities. Among them, compounds 4 – 7 and 8 exhibited antibacterial activities against S. aureus, B. subtilis, and P. aeruginosa, with MIC of 4–64 μg/mL.