Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Chem Biodivers ; : e2100672, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34519420

RESUMO

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).

2.
Fitoterapia ; 153: 104959, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34111550

RESUMO

Three new polyprenylated acylphloroglucinol meroterpenoids, hyperiforins A-C (1-3), were isolated from Hypericum forrestii (Chittenden) N. Robson, together with twelve known analogues (4-15). Their structures were established by extensive physical and spectroscopic data analysis. Compounds 1, 2, 5, 7, and 13-15 showed potent inhibitory effects on protein tyrosine phosphatase 1B with IC50 values from 6.63 ± 2.40 to 14.21 ± 3.51 µM.


Assuntos
Hypericum/química , Floroglucinol/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Terpenos/farmacologia , China , Estrutura Molecular , Floroglucinol/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Terpenos/isolamento & purificação
3.
Bioorg Chem ; 112: 104916, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33957537

RESUMO

Three unprecedented dimeric clerodane diterpenoids, dodovisdimers A-C (1-3), along with six known clerodane monomers (4-9), were isolated from Dodonaea viscosa. Compounds 1-3 may be biosynthetically formed via an intermolecular Diels-Alder [4+2] cycloaddition between the coexisting monomers 4-7. The structures of these clerodanes were characterized by spectroscopic techniques, X-ray crystallographic study, and ECD calculations. Some isolates exerted antiviral effects on human influenza A virus (H3N2) in vitro.

4.
Phytochemistry ; 187: 112765, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887558

RESUMO

Nine undescribed acylphloroglucinol derivatives, oblatones A-I, along with three known ones, were isolated from Syzygium oblatum. Their structures were determined on the basis of extensive spectroscopic analysis, including NMR and MS data interpretation. Oblatones A and B possess an alkylated chromanone scaffold featuring a hemiketal moiety. Oblatones C and D are the first acylphloroglucinol derivatives with an α,ß-unsaturated ketone lipid chain. Some of the isolates showed inhibitory effects on ATP citrate lyase in vitro. The binding mode of oblatone A was predicted by molecular docking.


Assuntos
Syzygium , ATP Citrato (pro-S)-Liase , Simulação de Acoplamento Molecular , Estrutura Molecular , Floroglucinol/farmacologia
5.
J Pharm Biomed Anal ; 198: 113993, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33677280

RESUMO

Three maytansinoids with strong cytotoxicities, dehydrotrewiasine, maytanbutine, and trewiasine, were isolated and identified from Trewia nudiflora, and maytanbutine was obtained from this plant for the first time. A quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction combined with high-performance liquid chromatography (HPLC) was established to determine the three maytansinoids in T. nudiflora. The effects of major factors on the extraction efficiency of the QuEChERS method were evaluated and the optimal conditions using acetonitrile-ethyl acetate (1:1, v/v) as the extraction solvent and PestiCarb as the clean-up sorbents were established. Compared with Soxhlet extraction (SE) and ultrasonic-assisted extraction (UAE), the QuEChERS method was easy-to-operate and afforded a cleaner extract. A phenomenex HyperClone BDS C18 column was used for HPLC analysis. Methanol-acetonitrile-water was chosen as mobile phase for gradient elution. Method validation showed that all analytes showed good linearity (r > 0.999) over the investigated ranges and satisfactory recoveries ranging from 95.0% to 105.0%. The developed QuEChERS-HPLC method was simple, efficient, and applicable to the determination of maytansinoids in T. nudiflora.


Assuntos
Espectrometria de Massas em Tandem , Água , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Solventes
6.
Phytochemistry ; 183: 112614, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33360008

RESUMO

Six undescribed clerodane diterpenoids, dodovisins A-F, together with nine known ones, were isolated from the aerial parts of Dodonaea viscosa (L.) Jacq. Their structures were elucidated by extensive spectroscopic techniques, X-ray crystallographic analysis, and ECD calculation. Dodovisins A and B possess a rare carbon skeleton featuring a bicyclo[6.2.0]decane motif. Dodovisins C-E represent the first clerodane diterpenoids with a 4(5 â†’ 19)-abeo-2,4,10(1)-triene moiety. Dodovisins A, E, and strictic acid showed potent inhibitory activities against ATP citrate lyase.


Assuntos
Diterpenos Clerodânicos , Sapindaceae , ATP Citrato (pro-S)-Liase , Diterpenos Clerodânicos/farmacologia , Estrutura Molecular
7.
Phytochemistry ; 180: 112524, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33038550

RESUMO

Eight pairs of meroterpenoid enantiomers and four achiral meroterpenoids were isolated from Rhododendron anthopogonoides Maxim. Seventeen of them, named (+)-/(-)-anthoponoids A-G, (+)-daurichromene D, and anthoponoids H and I, are undescribed compounds with structural diversity. Their structures were characterized herein by a combined application of spectroscopic techniques, X-ray crystallographic analysis, ECD calculation, and the modified Mosher's method. (+)-/(-)-Anthoponoid A and anthoponoid I are the first Rhododendron meroterpenoids found to possess a hexahydroxanthene motif and a diterpene unit, respectively. Some isolates were identified as NF-κB pathway inhibitors, and (+)-anthoponoid E, (-)-anthoponoid G, and anthoponoid H showed suppressive effects on LPS-induced inflammatory responses in RAW 264.7 macrophages.


Assuntos
Rhododendron , Anti-Inflamatórios/farmacologia , Cristalografia por Raios X , Diterpenos , Estereoisomerismo
8.
Org Lett ; 22(7): 2797-2800, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32186193

RESUMO

Hyperprins A (1) and B (2), two polyprenylated acylphloroglucinol related meroterpenoids with undescribed carbon skeletons, were isolated from Hypericum przewalskii. Compound 1 possesses a new 6/6/6/6/5/5 hexacyclic system with an unprecedented tetracyclo[10.3.1.03,8.08,12]hexadecane motif. Compound 2 features a unique 6/8/6/6 tetracyclic scaffold. Their structures were determined by spectroscopic data, chemical method, and X-ray crystallography. Compound 1 showed antiproliferation activity against the MV-4-11 cell line, and the p-bromobenzoate derivative of 2 displayed PTP1B inhibition.

9.
Nat Prod Bioprospect ; 10(1): 45-49, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32072482

RESUMO

Four new alkaloids, ficuhismines A-D (1-4), together with three known ones, were isolated from Ficus hispida. Their structures were elucidated by spectroscopic analysis and chemical method. The new compounds represent the first amine alkaloids with a rhamnosyl moiety (1-2) or with a N-oxide motif (2-4) from the genus Ficus. Compound 2 showed potent inhibitory effect in nuclear factor-κB (NF-κB) pathway luciferase assay with IC50 value of 0.52 ± 0.11 µM.

10.
Phytochemistry ; 171: 112229, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901474

RESUMO

Seven undescribed cycloartane triterpenoids, pseudolarnoids A-G, together with ten known ones, were isolated from the seeds of Pseudolarix amabilis (J. Nelson) Rehder. Their structures were elucidated on the basis of spectroscopic analysis, X-ray crystallography, and ECD data. Pseudolarnoids A-C are cycloartane triterpenoids with a unique 16S, 23R-spirolactone moiety. Pseudolarnoids F, G, and pseudolarolide C demonstrated potent antiviral effects on HSV-1 in vitro.


Assuntos
Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Triterpenos/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Cristalografia por Raios X , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Pinaceae/química , Triterpenos/química , Triterpenos/isolamento & purificação
11.
Chin J Nat Med ; 17(12): 963-969, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31882052

RESUMO

Five pairs of optically pure meroterpenoid enantiomers (1a/1b-5a/5b) and two known compounds (6 and 7) were isolated from Rhododendron fastigiatum. Compounds 1a/1b-5a/5b were resolved from naturally scalemic mixtures by chiral HPLC. Their structures were elucidated by spectroscopic methods, X-ray crystallographic experiments, and ECD analyses. Compounds 1a/1b, 2a/2b, 3b, 4a/4b, and 5a/5b were new meroterpenoids with different polycyclic systems. Two enantiomeric pairs (2a/2b and 3a/3b), 6, and 7 exhibited inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) in vitro.


Assuntos
Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Rhododendron/química , Terpenos/química , Terpenos/isolamento & purificação , China , Cromatografia Líquida de Alta Pressão , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Componentes Aéreos da Planta/química
12.
Fitoterapia ; 139: 104414, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31705950

RESUMO

Six new triterpenoids, pseudolarins A-F (1-6), were isolated from the twigs of Pseudolarix amabilis, together with four known triterpenoids (7-10) and five known diterpenoids (11-15). Their structures were determined by extensive spectroscopic analysis, and the absolute configuration of 1 was assigned by single-crystal X-ray diffraction. Compound 1 is a 3,4:9,10-diseco-cycloartane triterpenoid possessing an unprecedented 5/5/7/6/5/6/5 ring system. Compounds 1, 5, 7, 9-11, and 13 showed inhibition against protein tyrosine phosphatase 1B (PTP1B) in vitro.


Assuntos
Diterpenos/farmacologia , Pinaceae/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Triterpenos/farmacologia , China , Diterpenos/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Triterpenos/isolamento & purificação
13.
Zhongguo Zhong Yao Za Zhi ; 44(3): 495-499, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30989914

RESUMO

Twelve alkaloids were isolated from the bulbs of Fritillaria yuminensis by column chromatography over silica gel, ODS, and Sephadex LH-20, as well as RP-HPLC. Their structures were identified mainly by NMR and MS analyses as yubeinine(1), imperialine(2), delavinone(3), tortifoline(4), hupehenizioiside(5), imperialine-ß-D-glucoside(6), kuroyurinidine(7), pengbeisine A(8), walujewine A(9), peimisine-3-O-ß-D-glucopyranoside(10), solanidine-3-O-α-L-rhamnopyranosyl-(1→2)-ß-D-glucopyranoside(11), and solanidine-3-O-α-L-rhamnopyranosyl-(1→2)-[ß-D-glucopyranosyl-(1→4)]-ß-D-glucopyranoside(12). Compounds 4-12 were obtained from F. yuminensis for the first time.


Assuntos
Alcaloides/análise , Fritillaria/química , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos Fitoquímicos/análise
14.
Zhongguo Zhong Yao Za Zhi ; 44(1): 88-94, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30868817

RESUMO

Eleven flavonoids were isolated from the twigs of Broussonetia papyrifera by column chromatography over silica gel,ODS,MCI gel,and Sephadex LH-20,as well as RP-HPLC.Their structures were identified by spectroscopic methods including NMR,MS,UV,and IR as broupapyrin A(1),5,7,3',4'-tetrahydroxy-3-methoxy-8-geranylflavone(2),8-prenylquercetin-3-methyl ether(3),broussonol D(4),broussoflavonol B(5),uralenol(6),broussonol E(7),8-(1,1-dimethylallyl)-5'-(3-methylbut-2-enyl)-3',4',5,7-tetrahydroxyflanvonol(8),broussoflavonol E(9),4,2',4'-trihydroxychalcone(10),and butein(11).Compound 1 is a new isoprenylated flavonol.Compounds 3,6,10,and 11 were obtained from the genus Broussonetia for the first time,and 4 and 7 were firstly discovered in B.papyrifera.Compounds 1-5 and 7-9 showed significant inhibitory effects on PTP1 B with IC50 values ranging from(0.83±0.30) to(4.66±0.83) µmol·L-1.


Assuntos
Broussonetia/química , Flavonoides/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Espectroscopia de Ressonância Magnética , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia
15.
Fitoterapia ; 131: 112-118, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30336193

RESUMO

Three new isosteroidal alkaloids, frititorines A-C (1-3), were isolated from the bulbs of Fritillaria tortifolia, together with ten known ones (4-13). Their structures were elucidated by extensive spectroscopic analyses, chemical methods, and single-crystal X-ray crystallographic analysis. Compound 1 is the first 5ß-cevanine alkaloid with a cis A/B ring junction from the Fritillaria genus. Compound 2 is the first example of glycosylated isosteroidal alkaloid N-oxide. Compound 1 showed significant relaxant effect on Ach-induced tracheal contraction with pA2 and EC50 values equivalent to those of aminophylline.


Assuntos
Alcaloides/isolamento & purificação , Fritillaria/química , Raízes de Plantas/química , Traqueia/efeitos dos fármacos , Animais , China , Técnicas In Vitro , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Ratos Sprague-Dawley
16.
Chem Biodivers ; 15(11): e1800426, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30187609

RESUMO

Two new triterpenoids, vistriterpenoids A (1) and B (2), and four known ones, were acquired from Dodonaea viscosa. Compounds 1 and 2 represent the 24-nor-oleanane triterpenoids isolated from the genus Dodonaea for the first time. Their structures were identified based on extensive spectroscopic methods. Compounds 1, 2, 5, and 6 exerted inhibitory activities against PTP1B in vitro.


Assuntos
Inibidores Enzimáticos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Sapindaceae/química , Triterpenos/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Humanos , Conformação Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/isolamento & purificação
17.
J Nat Prod ; 81(8): 1810-1818, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30067363

RESUMO

Eight enantiomeric pairs of new meromonoterpenoids (1a/1b-8a/8b) and four known compounds (9-12) were isolated from Rhododendron nyingchiense. Their structures were established by spectroscopic methods, quantum chemical calculations, and X-ray crystallography. The enantiomeric pairs were acquired from scalemic mixtures by chiral-phase HPLC and showed diverse heterocyclic frameworks. Compounds 1a/1b possess a rare 6/7/5/5 heterocyclic system, and 2a/2b incorporate a new 6/6/3/5 heterocyclic system featuring a quinone motif. Compounds 3a/3b represent the first meroterpenoids with a 6/6/5 ring system from the Rhododendron genus. Putative biosynthetic pathways of these compounds are proposed. Compounds 1b, 2a-4a, 8a, 8b, and 11 exhibited weak inhibitory effects on PTP1B, with IC50 values ranging from 5.7 ± 0.5 to 61.0 ± 4.8 µM.


Assuntos
Compostos Heterocíclicos/química , Rhododendron/química , Terpenos/química , Animais , Cromatografia Líquida de Alta Pressão , Compostos Heterocíclicos/farmacologia , Camundongos , Estrutura Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Estereoisomerismo , Relação Estrutura-Atividade , Terpenos/farmacologia , Difração de Raios X
18.
Fitoterapia ; 130: 37-42, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30086333

RESUMO

Three new (1a/1b and 2b) and five known flavans (2a, 6a/6b, 7, and 8), one new flavan glycoside (3), and two new (4 and 5) and six known 1,3-diphenylpropanes (9-14) were isolated from the twigs of Broussonetia kazinoki. Compounds 1, 2, and 6 are scalemic mixtures, and were resolved by chiral HPLC to provide 1a/1b, 2a/2b, and 6a/6b. The structures of these compounds were elucidated by extensive spectroscopic methods, including NMR, MS, and ECD analyses. Compounds 1, 2, 5, 8, 9, 11, and 12 showed in vitro inhibition of protein tyrosine phosphatase 1B (PTP1B).


Assuntos
Broussonetia/química , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , China , Flavonoides/farmacologia , Glicosídeos/farmacologia , Estrutura Molecular , Compostos Fitoquímicos/farmacologia , Relação Estrutura-Atividade
19.
J Asian Nat Prod Res ; 20(5): 488-493, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29191050

RESUMO

A new isoprenylated sanggenon-type flavanone, nigrasin K (1), together with three known analogs (2-4) and five known Diels-Alder adducts (5-9), were isolated from the twigs of Morus nigra. Their structures were elucidated by spectroscopic methods. Sanggenon M (2), chalcomoracin (5), sorocein H (6), kuwanon J (7), sanggenon C (8), and sanggenon O (9) showed significant inhibitory effects on mushroom tyrosinase.


Assuntos
Monofenol Mono-Oxigenase/antagonistas & inibidores , Morus/química , Fenóis/química , Fenóis/farmacologia , Estrutura Molecular
20.
Planta Med ; 84(8): 500-506, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29017217

RESUMO

PPARγ agonists are widely used medications in diabetes mellitus therapy. Their role in improving adipose tissue function contributes to antidiabetic effects. The extracts of Dodonaea viscosa have been reported to exert antidiabetic activity. However, the effective mediators and the underlying mechanisms were largely unknown. In this study, we investigated the action on PPARγ transactivation and adipocyte modulation of two typical flavonoid constituents from D. viscosa, 5,4'-dihydroxy-7,8-dimethoxyflavanone and aliarin. Our results showed that 5,4'-dihydroxy-7,8-dimethoxyflavanone and aliarin were potential partial PPARγ agonists. The compounds induced adipogenesis in 3T3-L1 cells, with an upregulated adiponectin mRNA level and enhanced insulin sensitivity. The favorable effects of 5,4'-dihydroxy-7,8-dimethoxyflavanone, aliarin, and other flavonoid constituents on adipocytes might contribute to the antidiabetic efficacy of D. viscosa.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Flavanonas/farmacologia , Flavonoides/farmacologia , Hipoglicemiantes/agonistas , PPAR gama/agonistas , Sapindaceae/química , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Adiponectina/genética , Tecido Adiposo/efeitos dos fármacos , Animais , Flavanonas/química , Flavanonas/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Hipoglicemiantes/uso terapêutico , Resistência à Insulina , Camundongos , PPAR gama/uso terapêutico , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...