Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Nat Prod ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31916778

RESUMO

A thiazole-containing cyclic depsipeptide with 11 amino acid residues, named pagoamide A (1), was isolated from laboratory cultures of a marine Chlorophyte, Derbesia sp. This green algal sample was collected from America Samoa, and pagoamide A was isolated using guidance by MS/MS-based molecular networking. Cultures were grown in a light- and temperature-controlled environment and harvested after several months of growth. The planar structure of pagoamide A (1) was characterized by detailed 1D and 2D NMR experiments along with MS and UV analysis. The absolute configurations of its amino acid residues were determined by advanced Marfey's analysis following chemical hydrolysis and hydrazinolysis reactions. Two of the residues in pagoamide A (1), phenylalanine and serine, each occurred twice in the molecule, once in the d- and once in the l-configuration. The biosynthetic origin of pagoamide A (1) was considered in light of other natural products investigations with coenocytic green algae.

2.
J Asian Nat Prod Res ; : 1-6, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829036

RESUMO

Two new 1,3-benzodioxole derivatives, leucandioxoles A and B (1-2), together with two known related compounds (3-4), have been isolated from the South China Sea sponge Leucandra sp. The structures of all compounds were clearly elucidated on the basis of spectroscopic analyses and compared with the literatures. The cytotoxicity against A549, Hep G2, MDA-MB-231, and HeLa cell lines of 1-4 were evaluated. Only compound 1 exhibited moderate activity against MDA-MB-231 cells with the IC50 value of 7.98 ± 0.74 µM.

3.
J Nat Prod ; 82(11): 3089-3095, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31702148

RESUMO

The Arctic fungus Eutypella sp. D-1, previously found to produce a variety of cytotoxic cyclopropyl-fused and cyclobutyl-fused pimarane diterpenoids when grown in the defined medium, was induced to produce unusual metabolites by growing on solid rice medium. A chemical investigation on the rice medium extract led to the isolation of four new meroterpenoids, eutypellacytosporins A-D (1-4), along with the known biogenetically related compound cytosporin D (5). The structures of the new compounds were elucidated by their detailed spectroscopic analysis and modified Mosher's method. Compounds 1-4 may be formed by the 12,32-ester linkage of two moieties, cytosporin D (5) and decipienolide A or B. All isolated compounds, except 5, showed weak cytotoxicity against DU145, SW1990, Huh7, and PANC-1 cell lines with IC50 values ranging from 4.9 to 17.1 µM.

4.
J Nat Prod ; 82(9): 2608-2619, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31468974

RESUMO

Nine new linear lipopeptides, microcolins E-M (1-9), together with four known related compounds, microcolins A-D (10-13), were isolated from the marine cyanobacterium Moorea producens using bioassay-guided and LC-MS/MS molecular networking approaches. Catalytic hydrogenation of microcolins A-D (10-13) yielded two known compounds, 3,4-dihydromicrocolins A and B (14, 15), and two new derivatives, 3,4-dihydromicrocolins C and D (16, 17), respectively. The structures of these new compounds were determined by a combination of spectroscopic and advanced Marfey's analysis. Structurally unusual amino acid units, 4-methyl-2-(methylamino)pent-3-enoic (Mpe) acid and 2-amino-4-methylhexanoic acid (N-Me-homoisoleucine), in compounds 1-3 and 8, respectively, are rare residues in naturally occurring peptides. These metabolites showed significant cytotoxic activity against H-460 human lung cancer cells with IC50 values ranging from 6 nM to 5.0 µM. The variations in structure and attendant biological activities provided fresh insights concerning structure-activity relationships for the microcolin class of lipopeptides.

5.
Nat Prod Res ; : 1-7, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31232106

RESUMO

Three new sesquiterpene quinones/hydroquinones, 20-demethoxy-20-isopentylaminodactyloquinone D (1), 20-demethoxy-20-isobutylaminodactyloquinone D (2), and 19-methoxy-dictyoceratin-A (3), and five known related compounds (4-8) were isolated from the marine sponge Dactylospongia elegans. Their structures were elucidated by spectroscopic analysis, ECD calculation, single-crystal X-ray diffraction, and comparison with the literature. Compounds 3 and 5-8 exhibited activities against the human cancer cell lines DU145, SW1990, Huh7, and PANC-1 with IC50 values ranging from 2.33 to 37.85 µM.

6.
J Asian Nat Prod Res ; 21(10): 961-969, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29911892

RESUMO

Two new cyclohexanone derivatives, nectriatones A-B (1-2), and one new natural product, nectriatone C (3), together with three known phenolic sesquiterpene derivatives (4-6), were isolated from the culture of Nectria sp. B-13 obtained from high-latitude soil of the Arctic. The structures of all compounds were unambiguously elucidated by extensive spectroscopic analysis, as well as by comparison with the literature. These compounds were evaluated in cytotoxic and antibacterial activities. Compounds 1-6 showed cytotoxicities against SW1990, HCT-116, MCF-7, and K562 cells, with IC50 values in the range of 0.43 to 42.64 µM. Only compound 4 exhibited antibacterial activity against Escherichisa coli, Bacillus subtilis, and Staphylococcus aureus (MIC 4.0, 2.0, and 4.0 µg/ml, respectively).

7.
Mar Drugs ; 16(8)2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30115869

RESUMO

Three new pimarane diterpenes, eutypellenoids A⁻C (1⁻3), together with a known compound, eutypenoid C (4), were isolated from the culture extract of Eutypella sp. D-1 derived from the Arctic region. Compounds 1⁻3 possessed an uncommon tetrahydrofuran-fused pimarane diterpene skeleton. The structures of all compounds were determined by detailed spectroscopic analysis, electronic circular dichroism (ECD) analysis, as well as a comparison with the literature data. Antibacterial, antifungal, and cytotoxic activities of these compounds were evaluated. Compound 2 displayed antibacterial activity against Staphylococcus aureus and Escherichia coli with MIC values of 8 and 8 µg/mL, respectively. Additionally, compound 2 showed antifungal activity against Candidaparapsilosis, Candida albicans, Candida glabrata, and Candida tropicalis with MIC values of 8, 8, 16, and 32 µg/mL, respectively. Furthermore, compound 2 exhibited moderate cytotoxic activity against HCT-116 cell line with IC50 value of 3.7 µM.


Assuntos
/química , Diterpenos/química , Xylariales/química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Regiões Árticas , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Fungos/efeitos dos fármacos , Furanos/química , Células HCT116 , Humanos , Testes de Sensibilidade Microbiana/métodos , Staphylococcus aureus/efeitos dos fármacos
8.
J Nat Prod ; 81(7): 1553-1560, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-29949353

RESUMO

Seven new pimarane-type diterpene derivatives, libertellenones O-S (1-5) and eutypellenones A and B (6 and 7), together with two known compounds (8 and 9), were isolated from the culture of Eutypella sp. D-1 obtained from high-latitude soil of the Arctic. Their structures were elucidated from spectroscopic data, as well as experimental and calculated electronic circular dichroism (ECD) analysis. Structurally, compounds 1-5 possess a cyclopropyl-fused pimarane diterpene moiety, whereas compounds 6 and 7 share an unusual cyclobutyl-fused pimarane diterpene skeleton. Compounds 1-9 exhibited cytotoxicities against HeLa, MCF-7, HCT-116, PANC-1, and SW1990 cells, with IC50 values in the range of 0.3 to 29.4 µM. Compounds 6 and 7 could dose-dependently inhibit the activity of NF-κB and exhibited significantly inhibitory effects on nitric oxide production induced by lipopolysaccharide.


Assuntos
/isolamento & purificação , Xylariales/química , /química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Regiões Árticas , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Células HeLa , Humanos , Estrutura Molecular , Microbiologia do Solo
9.
J Asian Nat Prod Res ; 20(12): 1108-1115, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28990801

RESUMO

A new furanone derivative, butanolide A (1), and a new sesquiterpene, guignarderemophilane F (2), together with six known compounds, were isolated from the fungus Penicillium sp. S-1-18 derived from Antarctic marine. The new structures were determined by spectroscopic studies such as 1D- and 2D-NMR and MS analyses. The absolute configuration of 1 was determined by the modified Mosher's method, while the absolute configuration of 2 was determined by calculated ECD spectroscopy. The isolated secondary metabolites were evaluated for their protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Compound 1 showed moderate inhibitory activity against PTP1B with IC50 value of 27.4 µM.


Assuntos
Furanos/química , Penicillium/química , Sesquiterpenos/química , Regiões Antárticas , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular
10.
J Asian Nat Prod Res ; 20(7): 675-685, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28508666

RESUMO

The biotransformation of total coumarins of Radix Glehniae by Lecanicillium attenuatum W-1-9 yielded three new products, lecaniside A (1), lecaniside B (2), and lecaniside C (3). The chemical structures of these metabolites were elucidated based on extensive spectral data, including 2D NMR and HRMS. The hydrogenation, dealkylation, glycosylation, and O-methylation reactions of these metabolites were observed in the present study. In the in vitro assays, compound 1 displayed a little PTP1B inhibitory activity.


Assuntos
Apiaceae/metabolismo , Cumarínicos/química , Hypocreales/metabolismo , Apiaceae/química , Cromatografia Líquida de Alta Pressão , Cumarínicos/metabolismo , Meios de Cultura , Medicamentos de Ervas Chinesas/química , Hypocreales/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Raízes de Plantas/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores
11.
J Nat Prod ; 80(5): 1436-1445, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28398051

RESUMO

Nine new sesquiterpene quinones/hydroquinones (1-7, 10, and 12), three solvent-generated artifacts (8, 9, and 11), and three known compounds, 5-epi-smenospongine (13), smenospongine (14), and smenospongiadine (15), were isolated from the marine sponge Spongia pertusa Esper. The planar structures of the new compounds were elucidated on the basis of spectroscopic analyses. Their absolute configurations were determined by comparison between the calculated and experimental ECD spectra. In the cytotoxicity bioassay, compounds 13-15 exhibited activities against the human cancer cell lines U937, HeLa, and HepG2, with most potent cytotoxicities to U937 cells with IC50 values of 2.8, 1.5, and 0.6 µM, respectively. In addition, compound 6 displayed CDK-2 affinity with a Kd value of 4.8 µM in a surface plasmon resonance assay.


Assuntos
Células Hep G2/efeitos dos fármacos , Hidroquinonas/isolamento & purificação , Hidroquinonas/farmacologia , Poríferos/química , Quinonas/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Hidroquinonas/química , Concentração Inibidora 50 , Estrutura Molecular , Quinonas/química , Quinonas/isolamento & purificação , Sesquiterpenos/química
12.
Nat Prod Res ; 31(14): 1676-1681, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28278679

RESUMO

We isolated and identified a new sesquiterpene lactone which we named eut-Guaiane sesquiterpene (1), along with four cytochalasins from the fungus Eutypella sp. derived from the soil of high latitude of Arctic. The new structure was determined by spectroscopic studies such as 1D and 2D NMR and MS analyses, while the known compounds were identified by comparison of the NMR data with those in literatures. New compound 1 exhibited strong antibacterial activity against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Besides, it showed a little cytotoxicity against SGC7901 cell line.


Assuntos
Antibacterianos/química , Ascomicetos/química , Lactonas/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Antibacterianos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos de Guaiano , Staphylococcus aureus/efeitos dos fármacos
13.
Sci Rep ; 7: 43138, 2017 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-28224981

RESUMO

Hipposponlachnins A (1) and B (2), possessing an unprecedented tetracyclo [9.3.0.02,8.03,7] tetradecane ring system, and the probable biogenetic precursor [3, (1R*,2E,4R*,7E,10S*,11S*,12R*)-10, 18-diacetoxydolabella-2,7-dien-6-one] of 1‒2 were isolated from the South China Sea marine sponge Hippospongia lachne. The structures of the novel compounds were determined using integrated spectroscopic methods in combination with single-crystal X-ray diffraction analysis. Compounds 1‒2 showed potent inhibitory activity on the release of ß-hexosaminidase, a biomarker for degranulation, as well as the production of pro-inflammatory cytokine IL-4 and lipid mediator LTB4 in DNP-IgE-stimulated RBL-2H3 cells.


Assuntos
Antialérgicos/farmacologia , Organismos Aquáticos/química , Diterpenos/farmacologia , Poríferos/química , Animais , Antialérgicos/química , Antialérgicos/isolamento & purificação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , China , Cristalografia por Raios X , Diterpenos/química , Diterpenos/isolamento & purificação , Estrutura Molecular , Ratos , Água do Mar , Análise Espectral
14.
J Org Chem ; 81(12): 5135-43, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27232542

RESUMO

Fifteen polyketides, including the first hydroxylated plakortone (12) and plakdiepoxide (15), the first polyketide to embed a vicinal diepoxide, have been isolated from the Chinese sponge Plakortis simplex. The structures of the new metabolites were elucidated by analysis of spectroscopic data, Mosher's derivatization, and DFT computational calculations. The reactivity of the major endoperoxide of this sponge was investigated, suggesting that furan, furanylidene, and plakilactone derivatives, well-known classes of natural products, could actually be chemical degradation products. Plakdiepoxide is a potent and selective modulator of peroxisome proliferator-activated receptor (PPAR)-γ, while the diunsaturated C12 fatty acid monotriajaponide (13) activates both PPAR-α and PPAR-γ, a dual activity of potential great importance for the treatment of metabolic disorders.

15.
Bioorg Med Chem Lett ; 26(8): 2084-7, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26965857

RESUMO

Four new norterpene cyclic peroxides (1-4), together with three known norterpene cyclic peroxides were isolated from the Xisha Islands Sponge Diacarnus megaspinorhabdosa. Their structures were elucidated on the basis of spectroscopic analyses and comparison with the related model compounds. The compounds (1-7) were evaluated for the inhibitory activity against the malaria parasite Plasmodium falciparum, all of them showed significant antimalarial activity with IC50 values in the range of 1.6-8.6 µM.


Assuntos
Antimaláricos/farmacologia , Peróxidos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Poríferos/química , Animais , Antimaláricos/síntese química , Antimaláricos/química , Antimaláricos/isolamento & purificação , Relação Dose-Resposta a Droga , Estrutura Molecular , Testes de Sensibilidade Parasitária , Peróxidos/síntese química , Peróxidos/química , Peróxidos/isolamento & purificação , Relação Estrutura-Atividade
16.
J Asian Nat Prod Res ; 17(12): 1231-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26699877

RESUMO

Three new aaptamine derivatives (1-3), together with six known related compounds (4-9), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated on the basis of spectroscopic analyses. Compounds 1, 4, 5, 7, and 9 showed cytotoxic activities against HeLa, K562, MCF-7, and U937 cell lines with IC50 values in the range of 0.90-12.32 µM.


Assuntos
Antineoplásicos/isolamento & purificação , Naftiridinas/isolamento & purificação , Poríferos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , China , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Células K562 , Biologia Marinha , Estrutura Molecular , Naftiridinas/química , Naftiridinas/farmacologia , Células U937
17.
Mar Drugs ; 13(9): 5579-92, 2015 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-26343687

RESUMO

Two new furan derivatives, hypofurans A and B (1 and 2), and three new cyclopentenone derivatives, hypocrenones A-C (3-5), along with seven known compounds (6-12), were isolated from a marine fungus Hypocrea koningii PF04 associated with the sponge Phakellia fusca. Among them, compounds 10 and 11 were obtained for the first time as natural products. The planar structures of compounds 1-5 were elucidated by analysis of their spectroscopic data. Meanwhile, the absolute configuration of 1 was determined as 2R,3R by the comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. All the isolates were evaluated for their antibacterial and antioxidant activity. Compounds 1, 10, and 12 all showed modest antibacterial activity against Staphylococcus aureus ATCC25923 (MIC, 32 µg/mL). In addition, compounds 1, 10 and 11 exhibited moderate DPPH radical scavenging capacity with IC50 values of 27.4, 16.8, and 61.7 µg/mL, respectively.


Assuntos
Ciclopentanos/metabolismo , Furanos/metabolismo , Hypocrea/metabolismo , Poríferos/microbiologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ciclopentanos/química , Furanos/química , Estrutura Molecular
18.
Chem Pharm Bull (Tokyo) ; 63(6): 438-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26027468

RESUMO

Chemical investigation on CH2Cl2 extract of the marine sponge Diacarnus megaspinorhabdosa resulted in the isolation of two new farnesylacetone derivatives 1-2, a new γ-lactone 3, a known dinorditerpenone 4 and four known norsesterterpene peroxides 5-8. Their structures were elucidated by using one and two dimensional (1D and 2D)-NMR, high resolution-electrospray ionization (HR-ESI)-MS, and comparison with the literature. Compounds 1 and 2 were cis/trans-olefinic isomers and determined through nuclear Overhauser effect spectroscopy (NOESY) experiment. The absolute configuration of 3 was established by comparison of circular dichroism (CD) data with known lactones. The cytotoxic activities of the compounds were evaluated against five cancer cell lines, and compound 3 showed moderate cytotoxicity activities against cancer cell lines HeLa, H446, NCI-H460, SGC-7901 and MCF-7, with IC50 values in the range of 18.5 to 47.1 µM.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Lactonas/farmacologia , Peróxidos/farmacologia , Poríferos/química , Sesterterpenos/farmacologia , Terpenos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Linhagem Celular Tumoral , Células HeLa , Humanos , Lactonas/química , Lactonas/isolamento & purificação , Neoplasias/tratamento farmacológico , Peróxidos/química , Peróxidos/isolamento & purificação , Sesterterpenos/química , Sesterterpenos/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação
19.
J Nat Prod ; 78(5): 1169-73, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25932671

RESUMO

Four new macrocyclic lactones, bryostatin 21 (1) and 9-O-methylbryostatins 4, 16, and 17 (2-4), together with three known related compounds, bryostatins 4, 16, and 17 (5-7), have been isolated from an extract of the South China Sea bryozoan Bugula neritina. The structures of all compounds were unambiguously elucidated using detailed spectroscopic analysis. Structurally, the presence of a single methyl group at C-18 in compound 1 has not been observed before for known bryostatins. The isolated macrolides exhibited inhibitory effects against a small panel of human cancer cell lines.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Briostatinas/isolamento & purificação , Briostatinas/farmacologia , Briozoários/química , Macrolídeos/isolamento & purificação , Animais , Antineoplásicos/química , Briostatinas/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Macrolídeos/química , Macrolídeos/farmacologia , Estrutura Molecular , Oceanos e Mares
20.
J Nat Prod ; 78(1): 125-30, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25506718

RESUMO

(±)-Quassidines I (1) and J (2), two pairs of new bis-ß-carboline alkaloid enantiomers, were isolated from the stems of Picrasma quassioides. Their structures were determined by the analysis of spectroscopic data, including HRESIMS and 2D NMR, and confirmed by single-crystal X-ray diffraction analysis. The racemic mixtures of 1 and 2 were resolved into two pairs of enantiomers, (+)-S-1a and (-)-R-1b and (+)-S-2a and (-)-R-2b, by HPLC using a chiral Daicel IB-3 column, respectively, which represents the first successful example to resolve bis-ß-carboline racemic mixtures. The absolute configurations of the two pairs of enantiomers were determined by comparison between the calculated and experimental ECD spectra. The cytotoxicity evaluation revealed that (+)-S-1a and (+)-S-2a showed more potent cytotoxicity against human cervical HeLa and gastric MKN-28 cancer cell lines with IC50 values of 4.03-6.30 µM than their enantiomers with IC50 values of 9.64-12.3 µM; however, the two (+)-S-quassidines showed similar activities to their enantiomers against the mouse melanoma B-16 cancer cell line.


Assuntos
Alcaloides/isolamento & purificação , Carbolinas/isolamento & purificação , Picrasma/química , Alcaloides/química , Animais , Carbolinas/química , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Humanos , Camundongos , Estrutura Molecular , Estereoisomerismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA