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1.
Nat Prod Res ; : 1-7, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34822252

RESUMO

Phytochemical investigation of the fruits of Crataegus pinnatifida Bunge led to the isolation of four pairs enantiomeric benzofuran lignans (1a/1b-4a/4b) including four undescribed compounds (1a, 2b, 3b and 4b). Their structures were determined by extensive spectroscopic methods and the absolute configurations were further determined by the comparison of experimental and calculated ECD spectra. All the enantiomeric lignans were evaluated for their inhibitory activities to tyrosinase. Among them, compound 4a showed moderate inhibition activity (IC50 = 0.54 mM).

2.
J Org Chem ; 86(21): 15298-15306, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34612634

RESUMO

Daphnenoids A-C (1-3), three unusual sesquiterpenes with distinctive ring skeletons, together with a biogenetically related daphnenoid D (4) were obtained from the herb of Daphne penicillata by molecular networking strategies. Daphnenoid A (1) possesses a unique caged tetracyclo [5.3.2.01,6.04,11] dodecane scaffold by unexpected cyclizations of C-1/C-11 and C-2/C-14. Daphnenoids B and C (2 and 3) were the first discovered natural sesquiterpenes with unique 5/5 spirocyclic systems in nature. Their structures were determined by NMR spectroscopic analysis, computer-assisted structure elucidation methods, quantum chemical calculations, and X-ray diffraction. A hypothetical biogenetic pathway begins with typical guaiane sesquiterpene (a), including a key intermediate (4) was proposed. Daphnenoids B and C (2 and 3) exhibited potential inhibitory activities on the production of NO against LPS-induced BV2 microglial cells.

3.
Chin J Nat Med ; 19(9): 680-685, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34561079

RESUMO

Seven alkaloids including five undescribed ones (1a/1b, 2, 3 and 5) were obtained from the leaves of Isatis indigotica Fortune. Their structures were established by extensive spectroscopic analyses. The absolute configurations of compounds 1a, 1b, 3 and 5 were determined by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Subsequently, the neuroprotective effects of all the isolates against H2O2-induced injury in SH-SY5Y cells were evaluated in vitro by MTT assay. Moreover, Annexin V-FITC/PI double staining was performed, while the activities of antioxidant enzymes (SOD, CAT and GSH-Px) for compounds 1a and 1b were measured.


Assuntos
Alcaloides , Isatis , Fármacos Neuroprotetores , Alcaloides/farmacologia , Peróxido de Hidrogênio/toxicidade , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Folhas de Planta
4.
J Asian Nat Prod Res ; : 1-10, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34585635

RESUMO

Ten compounds (1-10) including four new compounds (1-4) and six known compounds (5-10) were isolated from Solanum nigrum. Their structures were elucidated on the basis of spectroscopic data, gauge-including atomic orbital (GIAO) calculation of NMR data, DP4+ probability analysis and comparison of their experimental and calculated electronic circular dichroism (ECD) spectral data. All the isolated compounds were tested for their neuroprotective activities against H2O2-induced damage in SH-SY5Y cells. Among them, compounds 1, 5 and 7 displayed moderate neuroprotective effects.

5.
Org Lett ; 23(18): 7231-7235, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34436914

RESUMO

Eleucanainones A and B are two structurally complex naphthoquinone-derived dimers whose structure identification is difficult. Large yellow fragments of the preliminary CASE (computer-assisted structure elucidation) analysis revealed that the original structures might be questionable. Structural revisions of the two compounds were proposed on the basis of NMR analysis, CASE methods, conformation analysis, and DFT (density functional theory) NMR calculations with a custom DP4+ analysis. In addition, a polyketide-folded biosynthetic pathway of the two revised structures was proposed.

6.
Phytochemistry ; 191: 112895, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34403885

RESUMO

Prenylated flavonoids, a unique class of flavonoids which combine a flavonoid skeleton and a lipophilic prenyl side-chain, possess great potential biological activities including cytotoxicity, anti-inflammation, anti-Alzheimer, anti-microbial, anti-oxidant, anti-diabetes, estrogenic, vasorelaxant and enzyme inhibition. Recently, prenylated flavonoids have become an indispensable anchor for the development of new therapeutic agents, and have received increasing from medicinal chemists. The prenylated flavonoids have been outstanding developed through isolation, semi or fully synthesis in a very short period of time, which proves the great value in medicinal chemistry researches. In this review, research progress of prenylated flavonoids including natural prenylated flavonoids, structural modification, synthetic methodologies and pharmacological activities was summarized comprehensively. Furthermore, the structure-activity relationships (SARs) of prenylated flavonoids were summarized which provided a basis for the selective design and optimization of multifunctional prenylated flavonoid derivatives for the treatment of multi-factorial diseases in clinic.


Assuntos
Antioxidantes , Flavonoides , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Prenilação , Relação Estrutura-Atividade
7.
Biochem Biophys Res Commun ; 567: 1-8, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34130179

RESUMO

Natural product-derived crude drugs are expected to yield an abundance of new drugs to treat infectious diseases. Hepatitis C virus (HCV) is an oncogenic virus that significantly impacts public health. In this study, we sought to identify anti-HCV compounds in extracts of natural products. A total of 110 natural compounds extracted from several herbal medicine plants were examined for antiviral activity against HCV. Using a Huh7-mCherry-NLS-IPS reporter system for HCV infection, we first performed a rapid screening for anti-HCV compounds extracted from crude drugs. The compounds threo-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-butoxypropan-1-ol (#106) and medioresinol (#110), which were extracted from Crataegus cuneate, exhibited anti-HCV activity and significantly inhibited HCV production in a dose-dependent manner. Analyses using HCV pseudoparticle and subgenomic replicon systems indicated that compounds #106 and #110 specifically inhibit HCV RNA replication but not viral entry or translation. Interestingly, compound #106 also inhibited the replication and production of hepatitis A virus. Our findings suggest that C. cuneate is a new source for novel anti-hepatitis virus drug development.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Extratos Vegetais/farmacologia , Antivirais/química , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Crataegus/química , Hepacivirus/fisiologia , Humanos , Extratos Vegetais/química , Plantas Medicinais/química , Replicação Viral/efeitos dos fármacos
8.
Eur J Med Chem ; 218: 113395, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33838584

RESUMO

A series of flavonoid-triazolyl hybrids were synthesized and evaluated as novel inhibitors of hepatitis C virus (HCV). The results of anti-HCV activity assays showed that most of the synthesized derivatives at a concentration of 100 µg/mL inhibited the generation of progeny virus. Among these derivatives, 10m and 10r exhibited the most potent anti-HCV activity and inhibited the production of HCV in a dose-dependent manner. Interestingly, 10m and 10r had no significant inhibitory effect on viral translation or replication. Additional action mechanism studies revealed that the most potent compounds, 10m and 10r, significantly inhibited viral entry to 34.0% and 52.0%, respectively, at 10 µM. These results suggest further effective application of 10m and 10r as potential HCV preventive agents.


Assuntos
Antivirais/farmacologia , Flavonoides/farmacologia , Hepacivirus/efeitos dos fármacos , Triazóis/farmacologia , Antivirais/síntese química , Antivirais/química , Relação Dose-Resposta a Droga , Flavonoides/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/química , Replicação Viral/efeitos dos fármacos
9.
Phytochemistry ; 187: 112769, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887559

RESUMO

Quassinoids, originating from the oxidative degradation of tetracyclic tirucallane triterpene, are a diverse class of secondary metabolites identifying from nature mostly in Simaroubaceae family. The crucial pharmacological activities and structural complexity of quassinoids have long fascinated scientists due to their medicinal uses, infamous toxicity, and unique biosynthesis. In the past few decades, 482 quassinoids, assigned to 6 skeletons, have been isolated and identified from plants. The names, classes, molecular formula, and plant sources of these secondary metabolites are collated here. This review will be a detailed update of the naturally occurring quassinoids reported from the plant kingdom, providing an in-depth discussion of their diversity, antitumor activities, structure-activity relationship.


Assuntos
Quassinas , Simaroubaceae , Extratos Vegetais , Plantas , Quassinas/farmacologia , Relação Estrutura-Atividade
10.
Bioorg Chem ; 110: 104802, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33730672

RESUMO

Ataxia telangiectasia and Rad3-related protein (ATR) plays a crucial role in cancer and has become a promising target for cancer therapy. Daphnegiravone D (DGD), which could induce apoptosis and oxidative stress in hepatocellular carcinoma (HCC) cells, but the detailed target protein was still unclear. The study provided that the possible target of DGD against HCC cells was determined by isobaric labels for relative and absolute quantification (iTRAQ) assay. In all changed proteins the fold change of ATR was particularly significant. The results from GO, KEGG and PPI analysis showed that DNA damage, cell cycle, apoptosis, DNA repair related pathways changed and ATR was exactly related to them. Moreover, the mRNA and protein of ATR were both decreased in a concentration-dependent manner, and the results of molecular docking also verified the binding. Additionally, cellular thermal shift assay (CETSA) suggested that DGD could directly target at ATR protein. Furthermore, the knockdown of ATR could increase apoptosis and reactive oxygen species (ROS) which induced by DGD. Since ATR inhibitors were generally used in combination with chemotherapy drugs (especially DNA damage drugs) in clinical trials, we investigated the combined application of DGD and oxaliplatin. The results showed that DGD combined with OXA also increased the apoptosis and ROS production of Hep3B cells over either drug alone. Taken together, this study revealed that DGD targeting ATR could be a promising therapeutic strategy for the treatment of liver cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Daphne/química , Flavonoides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Phytochemistry ; 184: 112675, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33548770

RESUMO

Seven undescribed tirucallane-type triterpenoids, kumunorquassins A‒E and kumuquassins K and L, along with nine known analogues, have been isolated from the leaves of Picrasma quassioides (D. Don) Benn. Their structures and absolute configurations were elucidated based on comprehensive spectroscopic analyses, single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD). The absolute configuration of cornusalterin J was unequivocally determined by X-ray diffraction based on its p-bromobenzoate derivative. A brief approach was presented in our study, which could rapidly and conveniently determine the relative and absolute configurations of OCH3-23 of kumuquassin L and cornusalterins J, H and G depending on the chemical shift differences (Δδ) of C-24 and C-25 and the chemical shifts of C-23, H-23 and H-24. In addition, the cytotoxicities of these compounds against two human tumour cell lines (HepG2 and Hep3B) were evaluated.


Assuntos
Picrasma , Triterpenos , Estrutura Molecular , Folhas de Planta , Triterpenos/farmacologia
12.
J Nat Prod ; 84(1): 20-25, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33415978

RESUMO

The structural elucidation of chiral molecules with more than one stereocenter is usually a tricky problem. In this paper, efficient 1H NMR spectroscopic approaches for assigning the erythro and threo configurations of 1-oxygenated 1,2-diarylpropan-3-ols were developed. By analysis of the chemical shift differences of diastereotopic methylene H2-3 (Δδ3) in CDCl3 or the chemical shift differences of H-1 and H-2 (Δδ1,2) in methanol-d4, deuterated dimethyl sulfoxide, and acetone-d6, the configurations of 1-oxygenated 1,2-diarylpropan-3-ols can be rapidly and conveniently determined.


Assuntos
1-Propanol/química , Dimetil Sulfóxido/química , Oxigênio/química , Espectroscopia de Ressonância Magnética/métodos , Estereoisomerismo
13.
Phytochemistry ; 183: 112628, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33412403

RESUMO

Nine undescribed guaiane-type sesquiterpenoids stelleraterpenoids A‒I, along with seven reported congeners, were isolated and identified from the 70% EtOH extract of the roots of Stellera chamaejasme L. Their chemical structures were elucidated on the basis of various spectral data. The relative configurations were determined by their NOESY spectra and comparison between their experimental and calculated NMR data. The absolute configurations were established by the comparison between the experimental and calculated ECD spectra and further by X-ray single-crystal diffraction analysis. The neuroprotective effects of these compounds on the H2O2-induced damage in human neuroblastoma SH-SY5Y cells were evaluated. Stelleraguaianone B exhibited the better activity with 71.62% cell viability compared to the positive control Trolox (65.05%) at 12.5 µM, which might be achieved by inhibiting the apoptosis of SH-SY5Y cells based on an annexin V-FITC/PI staining experiment.


Assuntos
Fármacos Neuroprotetores , Sesquiterpenos , Thymelaeaceae , Peróxido de Hidrogênio , Estrutura Molecular , Fármacos Neuroprotetores/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos de Guaiano
14.
Bioorg Chem ; 106: 104498, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33272710

RESUMO

Seven new diterpenoids (1-7), including five 7-membered ring vibsane-type diterpenoids, vibsanolide A-E (1-5) and a pair of epimers of 14,15,16,17-tetranorvibsane-type diterpenoids possessing bicyclo[4.2.1]nonane moiety, vibsanolide F-G (6-7), together with twelve known analogues (8-19) were isolated from the crude extracts of the leaves of Viburnum odoratissimum using Small Molecule Accurate Recognition Technology (SMART). These structures including absolute configurations were elucidated by means of comprehensive analyses of spectroscopic data, as well as comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. These compounds were evaluated for their cytotoxic activities against A549 and HepG2 cells by MTT assay. The results showed that compound 2 exhibited potent cytotoxic activity against A549 cells with IC50 value of 1.11 µM. Further staining experiments indicated that 2 could promote apoptosis induction, enhance reactive oxygen species (ROS) level and attenuate mitochondrial membrane potential (MMP) in A549 cells. Taken together, these findings provided new insights into understanding the cytotoxic activity of vibsane-type diterpenoids and it is meaningful to further investigate the application potential of V. odoratissimum.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Diterpenos/farmacologia , Extratos Vegetais/farmacologia , Viburnum/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
15.
J Asian Nat Prod Res ; 23(3): 217-227, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32102545

RESUMO

Four new alkaloids (1-4) and one known alkaloid were isolated from the stems of Picrasma quassioides. The structures of these isolated compounds were elucidated by spectroscopic analyses, a combination of computer-assisted structure elucidation software (ACD/Structure Elucidator) and gauge-including atomic orbital (GIAO) calculation of 1 D NMR data. All compounds were evaluated for their cytotoxic activities against hepatocellular carcinoma HepG2 and Hep3B cells. However, they did not show obvious inhibitory activities.[Figure: see text].


Assuntos
Alcaloides , Neoplasias Hepáticas , Picrasma , Alcaloides/farmacologia , Computadores , Humanos , Estrutura Molecular
16.
J Asian Nat Prod Res ; 23(2): 103-109, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32024382

RESUMO

Two new benzoic acid derivatives (1-2), together with four known compounds (3-6) have been isolated from the n-BuOH soluble fraction of ethanolic extract from Ailanthus altissima. The gross structures of the new compounds were deduced by detailed spectroscopic analysis including HRESIMS and 1D/2D NMR spectroscopy. The stereochemistry of 1 was determined by modified Mosher's method. All compounds were evaluated for their neuroprotective effects against H2O2-induced oxidative stress in human neuroblastoma SH-SY5Y cells and none of them displayed obvious neuroprotective activities. [Formula: see text].


Assuntos
Ailanthus , Ácido Benzoico , Peróxido de Hidrogênio/farmacologia , Estrutura Molecular , Extratos Vegetais
17.
J Asian Nat Prod Res ; 23(8): 738-744, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32627578

RESUMO

Three new compounds, crotalariapallins A-C (1-3), were isolated from the 95% EtOH extract of the seeds of Crotalaria pallida. Their structures were established based on extensive spectroscopic methods, including HRESIMS, UV, 1D and 2D NMR. All compounds were evaluated for their inhibitory activities to tyrosinase. These compounds showed different degrees of inhibitory activities, among them, compound 3 exhibited the strongest inhibition activity (IC50 = 0.42 mM).


Assuntos
Crotalaria , Estrutura Molecular , Monofenol Mono-Oxigenase , Sementes
18.
J Asian Nat Prod Res ; 23(6): 609-614, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32644854

RESUMO

Previous work has shown that the lignans from the twigs and leaves of Archidendron clypearia (Jack) I.C.N. possess anti-ß-amyloid aggregation activity. Here we report a new dilignan, archidendronin A (1), along with one known sesquilignan (2). Their structures were determined by extensive spectroscopic methods, including UV, HRESIMS, 1 D and 2 D NMR data. The inhibitory activity on Aß1-42 aggregation was screened by ThT assay with curcumin as the positive control, and compounds 1 and 2 showed inhibition rate of 60.0% and 64.4% at 20 µM, respectively.[Formula: see text].


Assuntos
Fabaceae , Lignanas , Estrutura Molecular , Extratos Vegetais , Folhas de Planta
19.
Nat Prod Res ; 35(4): 637-640, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30856004

RESUMO

Vibsane-type diterpenes, the characteristic compounds of Viburnum odoratissimum, exhibited significant cytotoxicity in many cancer cells. To search for the potential target of vibsane-type diterpenes on lung cancer, we combined methods of network pharmacology prediction and experimental verification. 80 active ingredients, 23 potential targets and 39 related pathways were analyzed through constructing the compound-target network and target-pathway network, and the potential target (EGFR) and key pathway (PI3K/Akt) were identified. Vibsanol C, an isolated vibsane-type diterpene with excellent cytotoxicity against lung cancer cells was chosen for further confirmation. Molecular docking study and drug affinity responsive target stability (DARTS) approach further indicated that EGFR is a direct target of Vibsanol C. Moreover, mechanistic studies revealed Vibsanol C might affect PI3K/Akt pathway by Western blot analysis. In conclusion, this study successfully predicted and confirmed the potential target of Vibsane-type diterpenes on lung cancer.


Assuntos
Antineoplásicos/farmacologia , Diterpenos/farmacologia , Viburnum/química , Linhagem Celular Tumoral , Diterpenos/isolamento & purificação , Humanos , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Nat Prod Res ; 35(7): 1139-1146, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31315448

RESUMO

Chemical investigation of 75% EtOH exact of the root bark of Ailanthus altissima (Mill.) Swingle led to the isolation and identification of two new phenylpropanoids (1-2), along with six known compounds (3-8). Their chemical structures were elucidated by extensive spectroscopic data analyses including NMR experiments and HRESIMS analyses, as well as computer-assisted structure elucidation software (ACD/Spectrus Processor). All compounds were evaluated for cytotoxic activities against Hep 3B and Hep G2 cells. Compound 1 and 7 displayed weak cytotoxic activities against the Hep 3B cell line.


Assuntos
Ailanthus/química , Casca de Planta/química , Raízes de Plantas/química , Propanóis/isolamento & purificação , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Propanóis/química , Propanóis/farmacologia , Espectroscopia de Prótons por Ressonância Magnética
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