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1.
Bioorg Med Chem Lett ; 28(4): 814-819, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29307497

RESUMO

Five new lignan racemates, (±)-tatarinoid D-H (1-5), and three known analogues (6-8) were isolated from the rhizomes of Acorus tatarinowii. Their structures were established by 1D, 2D-NMR, HR-MS, IR and optical spectral data. Among them, 1 and 6-8 can alleviate the cognitive deterioration of Aß transgenic flies.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Lignanas/uso terapêutico , Nootrópicos/uso terapêutico , Acorus/química , Peptídeos beta-Amiloides/genética , Animais , Animais Geneticamente Modificados/genética , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/genética , Lignanas/química , Lignanas/isolamento & purificação , Nootrópicos/química , Nootrópicos/isolamento & purificação , Fragmentos de Peptídeos/genética , Rizoma/química , Estereoisomerismo
2.
J Am Chem Soc ; 139(17): 6042-6045, 2017 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-28385018

RESUMO

The Salen unit represents one of the most important ligands in coordination chemistry. We report herein the first example of a Salen-based covalent organic framework (COF), in which both the construction of the COF structure and the functionalization with Salen moieties have been realized in a single step. Due to its structural uniqueness, the obtained COF material, Salen-COF, possesses high crystallinity and excellent stability. Based on this, a series of metallo-Salen-based COFs were prepared via metalation for further applications.

3.
J Nat Prod ; 80(11): 2923-2929, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29116780

RESUMO

Eight new (1a/1b, 2a, 3a, 4a/4b, and 5a/5b) and seven known (2b, 3b, and 6-10) asarone-derived phenylpropanoids, a known asarone-derived lignan (12), and four known lignan analogues (11 and 13-15) were isolated from the rhizome of Acorus tatarinowii Schott. The structures were elucidated via comprehensive spectroscopic analyses, modified Mosher's method, and quantum chemical calculations. Compounds 1-8 were present as enantiomers, and 1-5 were successfully resolved via chiral-phase HPLC. Compounds 1a/1b were the first cases of asarone-derived phenylpropanoids with an isopropyl C-3 side-chain tethered to a benzene core from nature. Hypoglycemic, antioxidant, and AChE inhibitory activities of 1-15 were assessed by the α-glucosidase inhibitory, ORAC, DPPH radical scavenging, and AChE inhibitory assays, respectively. All compounds except 3a showed α-glucosidase inhibitory activity. Compound 3b has the highest α-glucosidase inhibitory effect with an IC50 of 80.6 µM (positive drug acarbose IC50 of 442.4 µM). In the antioxidant assays, compounds 13-15 exhibited ORAC and DPPH radical scavenging activities. The results of the AChE inhibitory assay indicated that all compounds exhibited weak AChE inhibitory activities.


Assuntos
Acorus/química , Anisóis/química , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Medicamentos de Ervas Chinesas/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Fenilpropionatos/isolamento & purificação , Fenilpropionatos/farmacologia , Derivados de Alilbenzenos , Antioxidantes/análise , Inibidores da Colinesterase/química , Cromatografia Líquida de Alta Pressão , Inibidores de Glicosídeo Hidrolases/química , Lignanas/química , Estrutura Molecular , Fenilpropionatos/química , Rizoma/química , Estereoisomerismo , alfa-Glucosidases/efeitos dos fármacos
4.
Int J Qual Health Care ; 29(4): 442-449, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28541479

RESUMO

PURPOSE: Patient loyalty is key to business success for healthcare providers and also for patient health outcomes. This study aims to identify determinants influencing patient loyalty to healthcare providers and propose an integrative conceptual model of the influencing factors. DATA SOURCES: PubMed, CINAHL, OVID, ProQuest and Elsevier Science Direct databases were searched. STUDY SELECTION: Publications about determinants of patient loyalty to health providers were screened, and 13 articles were included. DATA EXTRACTION: Date of publication, location of the research, sample details, objectives and findings/conclusions were extracted for 13 articles. RESULTS OF DATA SYNTHESIS: Thirteen studies explored eight determinants: satisfaction, quality, value, hospital brand image, trust, commitment, organizational citizenship behavior and customer complaints. The integrated conceptual model comprising all the determinants demonstrated the significant positive direct impact of quality on satisfaction and value, satisfaction on trust and commitment, trust on commitment and loyalty, and brand image on quality and loyalty. CONCLUSION: This review identifies and models the determinants of patient loyalty to healthcare providers. Further studies are needed to explore the influence of trust, commitment, and switching barriers on patient loyalty.


Assuntos
Comportamento do Consumidor , Satisfação do Paciente , Relações Profissional-Paciente , Pessoal de Saúde/normas , Relações Hospital-Paciente , Humanos , Qualidade da Assistência à Saúde , Confiança
5.
J Nat Prod ; 78(6): 1221-30, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-25978520

RESUMO

Eight new viridins, nodulisporiviridins A-H (1-8), were isolated from the extract of an endolichenic fungal strain Nodulisporium sp. (No. 65-17-2-1) that was fermented with potato-dextrose broth. The structures were determined using spectroscopic and X-ray crystallographic analysis. Nodulisporiviridins A-D (1-4) are unique viridins with an opened ring A. The Aß42 aggregation inhibitory activities of 1-8 were evaluated using a thioflavin T (ThT) assay with epigallocatechin gallate (EGCG) as the positive control (EGCG IC50 of 0.5 µM). Nodulisporiviridin G (7) displayed potent inhibitory activity with an IC50 value of 1.2 µM, and the preliminary trend of activity of these viridins as Aß42 aggregation inhibitors was proposed. The short-term memory assay on an Aß transgenic drosophila model of Alzheimer's disease showed that all eight compounds improved the short-term memory capacity, with potencies close to that of the positive control (memantine).


Assuntos
Androstenos/isolamento & purificação , Androstenos/farmacologia , Bacteriocinas/isolamento & purificação , Bacteriocinas/farmacologia , Xylariales/química , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Androstenos/química , Animais , Bacteriocinas/química , Catequina/análogos & derivados , China , Cristalografia por Raios X , Modelos Animais de Doenças , Humanos , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Fragmentos de Peptídeos
7.
Food Chem ; 214: 644-654, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27507521

RESUMO

Nine new phenylpropanoids, one new coumarin, and 43 known polyphenols were isolated from wolfberry. Their structures were determined by spectroscopic analyses, chemical methods, and comparison of NMR data. Polyphenols, an important type of natural products, are notable constituents in wolfberry. 53 polyphenols, including 28 phenylpropanoids, four coumarins, eight lignans, five flavonoids, three isoflavonoids, two chlorogenic acid derivatives, and three other constituents, were identified from wolfberry. Lignans and isoflavonoids were firstly reported from wolfberry. 22 known polyphenols were the first isolates from the genus Lycium. This research presents a systematic study on wolfberry polyphenols, including their bioactivities. All these compounds exhibited oxygen radical absorbance capacity (ORAC), and some compounds displayed DPPH radical scavenging activity. One compound had acetylcholinesterase inhibitory activity. The discovery of new polyphenols and their bioactivities is beneficial for understanding the scientific basis of the effects of wolfberry.


Assuntos
Flavonoides/análise , Sequestradores de Radicais Livres/química , Lycium/química , Polifenóis/análise , Acetilcolinesterase/química , Doença de Alzheimer , Benzotiazóis , Compostos de Bifenilo/química , Ácido Clorogênico/análise , Inibidores da Colinesterase/química , Análise de Alimentos/métodos , Radicais Livres/química , Lignanas/química , Estrutura Molecular , Oxigênio/química , Picratos/química , Extratos Vegetais/química , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade , Tiazóis/química
8.
Chin Med ; 11: 10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26958073

RESUMO

BACKGROUND: Ligusticum chuanxiong Hort. (Chuanxiong) is a well-known Chinese medicine, and studies on its chemical constituents are important for explaining its mechanism of action and quality control. This study aims to investigate the chemical constituents of the dried rhizome of. L. chuanxiong. METHODS: The dried rhizome of L. chuanxiong was extracted with 60 % ethanol, and the concentrated extract was isolated by silica gel, octadecyl silane, and Sephadex LH-20 columns, followed by preparative/semipreparative high-performance liquid chromatography (HPLC) to obtain the pure chemical constituents. The structures of the constituents were elucidated by HR-ESI-MS, UV, IR, 1D NMR, and 2D NMR methods. Enantiomeric separation was achieved by a chiral HPLC method. The absolute configuration was determined by the modified Mosher's method. RESULTS: Six novel phthalide derivatives, (+)/(-)-chuanxiongins A-F (1-6), together with four known phthalides (7-10) were isolated from Chuanxiong. All of the new compounds (1-6) were present as pairs of enantiomers. Enantiomeric separation of 1 was successfully achieved by HPLC on a chiral column. The absolute configuration of (-)-1 was determined by a modified Mosher's method. CONCLUSION: The six novel phthalide derivatives (1-6) isolated from Chuanxiong were phthalide fatty acid esters that were structurally analogous and characterized by fatty acid acylation at 6-OH or 7-OH.

9.
Aging Cell ; 14(5): 784-96, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26010330

RESUMO

Aberrant neural progenitor cell (NPC) proliferation and self-renewal have been linked to age-related neurodegeneration and neurodegenerative disorders including Alzheimer's disease (AD). Rhizoma Acori tatarinowii is a traditional Chinese herbal medicine against cognitive decline. In this study, we found that the extract of Rhizoma Acori tatarinowii (AT) and its active constituents, asarones, promote NPC proliferation. Oral administration of AT enhanced NPC proliferation and neurogenesis in the hippocampi of adult and aged mice as well as that of transgenic AD model mice. AT and its fractions also enhanced the proliferation of NPCs cultured in vitro. Further analysis identified α-asarone and ß-asarone as the two active constituents of AT in promoting neurogenesis. Our mechanistic study revealed that AT and asarones activated extracellular signal-regulated kinase (ERK) but not Akt, two critical kinase cascades for neurogenesis. Consistently, the inhibition of ERK activities effectively blocked the enhancement of NPC proliferation by AT or asarones. Our findings suggest that AT and asarones, which can be orally administrated, could serve as preventive and regenerative therapeutic agents to promote neurogenesis against age-related neurodegeneration and neurodegenerative disorders.


Assuntos
Acorus/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Anisóis/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Fatores Etários , Derivados de Alilbenzenos , Animais , Anisóis/química , Anisóis/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurogênese/efeitos dos fármacos
10.
Org Lett ; 14(11): 2758-61, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22616819

RESUMO

Two C(18)-diterpenoid alkaloids, puberunine (1) and puberudine (2), together with four other new alkaloids, including the first examples having ß-oriented substitution at C-3 and a rare chloro-substituent were isolated from Aconitum barbatum var. puberulum. Their structures were elucidated by spectroscopic methods. Puberunine and puberudine, which possess a unique rearranged E ring and an opened A ring, respectively, represent new subtypes of the C(18)-diterpenoid alkaloids. A plausible biosynthetic pathway of 1 and 2 was proposed.


Assuntos
Aconitum/química , Alcaloides/química , Alcaloides/isolamento & purificação , Diterpenos/química , Diterpenos/isolamento & purificação , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
11.
Fitoterapia ; 83(3): 563-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22245087

RESUMO

A new lignan glucoside, (+)-(7S,8R,8'R)-lyoniresinol 9-O-ß-D-(6″-O-trans-sinapoyl)glucopyranoside (1), and a new iridoid glucoside, 10-O-trans-sinapoylgeniposide (2), together with eight known compounds, were isolated from the fruits of Gardenia jasminoides Ellis. The structures of the isolates were elucidated by extensive spectroscopic studies, including UV, IR, 1D and 2D NMR, ESI-MS, HR-ESI-MS, and CD experiments. The short-term-memory-enhancement activities of some compounds were evaluated on an Aß transgenic drosophila model.


Assuntos
Frutas/química , Gardenia/química , Glicosídeos/isolamento & purificação , Iridoides/isolamento & purificação , Lignanas/isolamento & purificação , Memória de Curto Prazo/efeitos dos fármacos , Nootrópicos/isolamento & purificação , Extratos Vegetais/química , Doença de Alzheimer/tratamento farmacológico , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Drosophila , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Iridoides/química , Iridoides/farmacologia , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Nootrópicos/farmacologia , Nootrópicos/uso terapêutico , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
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