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2.
J Agric Food Chem ; 66(34): 8976-8982, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30095908

RESUMO

Five new resorcylic acid lactones (RALs) hispidulactones A-E (1, 4, 5, 8, and 9), a new natural product (2), and four known ones (3, 6, 7, and 10) with different ring systems were isolated from the desert plant Chaetosphaeronema hispidulum. [corrected]. The new compounds were characterized by NMR data, CD spectra, and X-ray experiment. The new natural product (2) displayed strongly biological effects on the seedlings growth of Arabidopsis thaliana, Digitaria sanguinalis, and Echinochloa crusgalli with a dose-dependent relationship. Compounds 1, 2, and 6 were also tested cytotoxic activities against three cancer cell lines HCT116, Hela, and MCF7 and only did the new natural product (2) display biological activities with IC50 values at 54.86 ± 1.52, 4. 90 ± 0.02, and 20.04 ± 4.00 µM, respectively, whereas the IC50 values of the positive control cis-platinum were 11.36 ± 0.42, 3.54 ± 0.12, and 14.32 ± 1.01 µM, respectively.


Assuntos
Ascomicetos/química , Endófitos/química , Lactonas/química , Lactonas/farmacologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/microbiologia , Sobrevivência Celular/efeitos dos fármacos , Digitaria/crescimento & desenvolvimento , Digitaria/microbiologia , Echinochloa/crescimento & desenvolvimento , Echinochloa/microbiologia , Células HCT116 , Células HeLa , Humanos , Lactonas/isolamento & purificação , Estrutura Molecular
3.
Org Lett ; 20(7): 1806-1809, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29537276

RESUMO

The highly photosensitive characteristic of poly-sulfide chetomins was first unveiled, and four new unstable analogues, chetomins A-D (1-4), with significant cytotoxicity were successfully purified in darkness. The visible-light-induced desulfurization and intermolecular disproportionation were revealed to initiate the interconversion of chetomin analogues, which explained the long-recognized puzzle of rarity and instability of chetomin analogues.


Assuntos
Dissulfetos/química , Alcaloides Indólicos/química , Chaetomium , Estrutura Molecular , Processos Fotoquímicos , Enxofre
4.
J Antibiot (Tokyo) ; 71(6): 613-617, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29540777

RESUMO

Endophytic fungi from desert, arid, and grassland areas are an ecologically important but unique group with poor chemical investigation. During our ongoing study to mine bioactive secondary metabolites from unique fungal environments, a new shunt product spiciferone F (1) including two new analogs spiciferones G (2) and H (3) together with four known ones spiciferone A (4), spiciferol A (5), 6, and 7 were isolated from endophytic fungus Phoma betae inhabiting in plant Kalidium foliatum (Pall.) Moq from Ningxia Province of West China. The planar, relative, and absolute configurations of these new compounds were elucidated by nuclear magnetic resonance, high-resolution electrospray ionization mass spectrometry, and electronic circular dichroism experiments. According to the shunt products, intermediates and analogs isolated from this endophytic fungus, the possible biosynthetic pathway of spiciferones was reconstructed. Compounds 1-7 were evaluated cytotoxic activities against three cancer cell lines HCT 116, HeLa, and MCF7, and only did 1 display strong biological effect against MCF7 with a half-maximal inhibitory concentration value at 7.73 ± 0.11 µM compared with the cis-platinum (14.32 ± 1.01 µM).


Assuntos
Ascomicetos/química , Endófitos/química , Compostos Heterocíclicos com 2 Anéis/farmacologia , Plantas/microbiologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , China , Dicroísmo Circular , Clima Desértico , Compostos Heterocíclicos com 2 Anéis/isolamento & purificação , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
5.
J Nat Prod ; 80(6): 1944-1947, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28571311

RESUMO

Trichoderpyrone (1), a unique polyketide with a cyclopentenone-pyrone hybrid skeleton, was isolated from the plant endophytic fungus Trichoderma gamsii. The structure of 1 was determined by detailed analysis of NMR data together with comparison of chemical shift values of similar fragments. The relative and absolute configurations were established by NOESY correlations and CD experiment. Trichoderpyrone (1) displayed weak cytotoxic activities against A549, HepG2, and HeLa cancer cell lines. 1 might originate from a hybrid biosynthetic pathway through two nonreduced (NR) polyketide megasynthetases.


Assuntos
Policetídeos/isolamento & purificação , Trichoderma/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Células Hep G2 , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Plantas/microbiologia , Policetídeos/química , Policetídeos/farmacologia
6.
J Asian Nat Prod Res ; 19(11): 1102-1107, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28361583

RESUMO

Two new unsaturated fatty acids, (Z)-octadec-13-en-11-ynoic acid (1) and (Z)-octadec-16-en-12,14-diynoic acid (2), along with six known compounds were isolated from the whole plant of Pothos chinensis. The structures of these compounds were elucidated by detailed spectroscopic analysis, including 1D and 2D NMR data. Compound 2 showed moderate antibacterial activity against Staphylococcus aureus.


Assuntos
Antibacterianos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Ácidos Graxos Insaturados/isolamento & purificação , Antibacterianos/química , Antibacterianos/farmacologia , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/farmacologia , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo
8.
Zhongguo Zhong Yao Za Zhi ; 40(11): 2144-7, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26552171

RESUMO

The triterpenoids of Dichrocephala benthamii were investigated by means of silica gel, Sephadex LH-20 and semi-preparative HPLC. Nine triterpenoids were isolated from D. benthamii. By analysis of the EI-MS, NMR spectra and comparison to the data reported in literatures, the structures of these compounds were determined as ß-amyrin formiate (1), ß-amyrin acetate (2), ß-amyrenol (3), ß-amyrone (4), 3ß-hydroxy-olean-11, 13 (18)-diene (5) , Δ12-oleanene (6) , friedelin (7), dammaradienyl acetate (8), epi-friedeband (9), respectively. Compounds 1-8 were isolated for the first time form this genus, compound 9 was isolated for the first time from this plant, whereas ß-amyrin formiate (1) was a new natural product.


Assuntos
Asteraceae/química , Triterpenos/isolamento & purificação , Triterpenos/química
9.
Nat Prod Res ; 29(9): 795-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25560313

RESUMO

A new ellagic acid derivative, 3,3'-dimethylellagic acid-4'-O-(6″-galloyl)-ß-D-glucoside, named runcinatside (5), together with four known compounds 3,3'-dimethylellagic acid (1), 3,3',4'-trimethylellagic acid (2), 3,3'-dimethylellagic acid-4'-O-ß-D-glucoside (3) and 3-methylellagic acid-4'-O-α-L-rhamno-pyranoside (4), was isolated from the roots of Polygonum runcinatum Buch.-Ham. ex D.Don Var. sinense Hemsl and the structures of these compounds were established by spectroscopic methods and comparison with previously reported data. All compounds showed antioxidant activities in vitro and compound 5 possessed the highest activity.


Assuntos
Antioxidantes/química , Ácido Elágico/análogos & derivados , Raízes de Plantas/química , Polygonaceae/química , Ácido Elágico/química , Ácido Elágico/isolamento & purificação , Glucosídeos/química , Glucosídeos/isolamento & purificação , Concentração Inibidora 50 , Estrutura Molecular
10.
Nat Prod Res ; 28(20): 1772-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995563

RESUMO

A new flavone glycoside, wogonin 7-O-ß-D-ethylglucuronide (1), together with a new natural flavone glycoside baicalein 7-O-ß-D-ethylglucuronide (2) and four known analogues, wogonoside (3), wogonin (4), oroxylin A 7-O-ß-D-methylglucuronide (5) and oroxylin A (6), was isolated from the roots of Scutellaria baicalensis Georgi. The structure elucidation of the new compound was primarily based on HR-ESI-MS, 1D and 2D NMR analyses. Compounds 1 and 3 inhibited FeSO4-Cys-induced liver homogenate lipid peroxidation with IC50 at 18.2 µM and 24.9 µM, respectively, and exhibited strong cytoprotective effects against H2O2-induced oxidative damage in human umbilical vein endothelial cells at low concentrations of 10.0 µM and 3.0 µM.


Assuntos
Antioxidantes/química , Flavanonas/química , Flavonas/química , Glucuronídeos/química , Glicosídeos/química , Raízes de Plantas/química , Scutellaria baicalensis/química , Animais , Antioxidantes/isolamento & purificação , Flavanonas/isolamento & purificação , Flavonas/isolamento & purificação , Glucuronídeos/isolamento & purificação , Glicosídeos/isolamento & purificação , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos , Fígado/efeitos dos fármacos , Estrutura Molecular , Estresse Oxidativo , Ratos
11.
Nat Prod Res ; 28(15): 1214-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24896299

RESUMO

Eleven compounds, including four flavonoids [(2R,3R)-2,3-dihydro-3,5-dihydroxy-7,4'-dimethoxyflavone (1), 5-hydroxy-7,8,4'-trimethoxy-flavone (2), amentoflavone (10) and apigenin (11)], two penylpropanoids [sinapaldehyde (3) and 3-methoxy-4-hydroxy-cinnamic aldehyde (4)], three phenolic acids [4-hydroxyl-3,5-dimethoxy-benzaldehyde (5), 4-hydroxyacetophen-one (6) and p-hydroxybenzaldehyde (7)], one furan derivative [5-hydroxymethyl furfural (8)] and one steroid saponin [ß-sitosterol-3-O-ß-d-glucoside (9)], were isolated and identified from Aletris spicata. Among them, compounds 1-7, 9 and 10 were reported from the genus Aletris for the first time. Furthermore, seven of them (1-6, 10) were obtained from the family Liliaceae for the first time. Chemotaxonomy of the isolated compounds is discussed briefly.


Assuntos
Flavonoides/isolamento & purificação , Liliaceae/química , Magnoliopsida/química , Plantas Medicinais/química , Apigenina/química , Apigenina/isolamento & purificação , Benzaldeídos/química , Flavonas/química , Flavonas/isolamento & purificação , Flavonoides/química , Furaldeído/análogos & derivados , Furaldeído/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Filogenia , Sitosteroides/química
12.
Nat Prod Res ; 28(8): 530-3, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24579793

RESUMO

Taxadiene (3), a new taxane diterpenoid with an unusual hydroxy substituting at C-17, and six known compounds including two taxane diterpenoids (1 and 2) and four flavonoids (4-7) were isolated from the whole seedling of the Taxus chinensis var. mairei. Among them, compound 7 was isolated from T. chinensis var. mairei for the first time. Structures of these compounds were elucidated on the basis of spectroscopic data and by comparison with reported literature data.


Assuntos
Alcenos/isolamento & purificação , Diterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/isolamento & purificação , Taxoides/isolamento & purificação , Taxus/química , Alcenos/química , Diterpenos/química , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Flavonoides/isolamento & purificação , Ressonância Magnética Nuclear Biomolecular , Taxoides/química
13.
J Opt Soc Am A Opt Image Sci Vis ; 24(9): 2748-57, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17767244

RESUMO

Different geometric shapes of light pipes cause different irradiance distributions. We analytically explore the irradiance distributions of on-axis Lambertian pointlike sources in polygonal total-internal-reflection (TIR) straight light pipes. It is analytically shown that the irradiance of pentagonal light pipes concentrates on the center of the exit plane. Numerical verifications are also provided, and experimental explorations with different shapes of acrylic light pipes are carried out for comparison. We also analyze the influence of light-pipe length on distribution uniformity and deduce the smallest uniform-mixing length/circumradius ratios for polygonal light pipes.

14.
Zhonghua Yan Ke Za Zhi ; 42(1): 48-53, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16638281

RESUMO

OBJECTIVE: To establish an in vitro model of posterior capsule opacification (PCO) by culturing the posterior capsule of bovine lens, to observe the proliferation and differentiation of lens epithelial cells and to study the influence of serum and pranoprofen eyedrops on cell confluence of this model. METHODS: The bovine lens posterior capsule was spread on the surface of a 25 ml culture flask with cell layer upward. DMEM with 0%, 10% and 20% fetal calf serum was used as culture medium. The cell coverage and confluence time on the posterior capsule were observed by inverted microscope and the cell morphology was observed by Giemsa staining and scanning electron-microscope. Pranoprofen was added to the culture medium at a concentration similar to the aqueous humor concentration (0.23 mg/L), which was presented at 4 hours after the instillation of pranoprofen eyedrops. The difference of confluence time between the treated group and the control group was compared. RESULTS: The lens epithelial cells migrated and proliferated rapidly on the posterior capsule from the equatorial region to the center. The cell coverage was increased and the confluence time was shortened with the increase of serum concentration (P < 0.05). The PCO and wrinkles were presented. Pranoprofen at 0.23 mg/L could inhibit the confluence of lens epithelial cells (P < 0.01). CONCLUSIONS: The in vitro model for PCO was an useful method to study the mechanism of PCO formation. Pranoprofen can inhibit the proliferation of lens epithelial cells and is a safe and efficient drug for preventing the occurrence of PCO and can be used as a routine medication after the cataract operation.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Benzopiranos/farmacologia , Cápsula do Cristalino/efeitos dos fármacos , Propionatos/farmacologia , Animais , Bovinos , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/patologia , Cápsula do Cristalino/patologia , Cristalino/patologia , Soluções Oftálmicas , Técnicas de Cultura de Órgãos
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