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1.
Nat Commun ; 15(1): 4580, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811566

RESUMO

Chirality constitutes an inherent attribute of nature. The catalytic asymmetric synthesis of molecules with central, axial, and helical chirality is a topic of intense interest and is becoming a mature field of research. However, due to the difficulty in synthesis and the lack of a prototype, less attention has been given to planar chirality arising from the destruction of symmetry on a single planar ring. Herein, we report the catalytic asymmetric synthesis of planar-chiral dianthranilides, a unique class of tub-shaped eight-membered cyclic dilactams. This protocol is enabled by cinchona alkaloid-catalyzed (dynamic) kinetic resolution. Under mild conditions, various C2- or C1-symmetric planar-chiral dianthranilides have been readily prepared in high yields with excellent enantioselectivity. These dianthranilides can serve as an addition to the family of planar-chiral molecules. Its synthetic value has been demonstrated by kinetic resolution of racemic amines via acyl transfer, enantiodivergent synthesis of the natural product eupolyphagin, and preliminary antitumor activity studies.

2.
iScience ; 26(10): 107978, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37822512

RESUMO

Reported herein is a highly efficient dynamic kinetic resolution protocol for the atroposelective synthesis of heterobiaryls with vicinal C-C and N-N diaxes. Atropisomers bearing vicinal diaxes mainly exist in o-triaryls, while that of biaryls is highly challenging in terms of the concerted rotation and deplanarization effects. The combination of C-C biaryl with N-N nonbiaryl delivers a novel class of vicinal-diaxis heterobiaryls. For their atroposelective synthesis, the dynamic kinetic resolution enabled by either quinine-catalyzed allylation or isothiourea-catalyzed acylation has been developed, allowing the preparation of a wide range of vicinal-axis heterobiaryls in good yields with excellent enantioselectivities. Atropisomerization experiments revealed that the C-C bond rotation led to diastereomers, and the N-N bond rotation offered enantiomers. Besides, this protocol could be extended to kinetic resolution by employing substrates with a more hindered axis.

3.
Bioorg Chem ; 83: 1-5, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30339860

RESUMO

Two new monoterpene indole alkaloids, naucleaoffines A (1) and B (2), together with six known alkaloids (3-8), were isolated from the stems and leaves of Nauclea officinalis. The structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with the data reported in literature. All isolated compounds were evaluated for their anti-inflammatory activities and anti-HIV-1 activities. Compounds 1-8 exhibited significant inhibitory activities on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro with IC50 values comparable to that of hydrocortisone. In addition, compounds 1-8 showed significant anti-HIV-1 activities with EC50 ranged from 0.06 to 2.08 µM. These findings suggest that the discoveries of these indole alkaloids with significant anti-inflammatory activities and anti-HIV-1 activities isolated from N. officinalis could be of great importance to the development of new anti-inflammatory and anti-HIV agents.


Assuntos
Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Alcaloides Indólicos/farmacologia , Monoterpenos/farmacologia , Rubiaceae/química , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Relação Dose-Resposta a Droga , HIV-1/efeitos dos fármacos , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Monoterpenos/química , Monoterpenos/isolamento & purificação , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Células RAW 264.7 , Relação Estrutura-Atividade
4.
Curr Med Sci ; 38(2): 360-371, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30074198

RESUMO

Based on the outpatient interview and literature review, the initial framework of the outpatient experience of human caring scale was formed with 9 dimensions of outpatient process. The research aim was to improve the scale by Delphi method. Sixteen experts in medical management, human caring or medical education were invited to evaluate the importance of the dimensions and items of the scale and provided some expertise via filling out the Delphi consultation questionnaires twice in the consulting round. In the first round, the recovery rate showing the experts' positivity was 80%; the coefficient of reliability (Cr) ascertaining the authority of the evaluation was 0.92; the mean and full mark ratios responding the concentration of the evaluation were 2.88-4.94 and 6.25%-93.75% respectively; the coefficients of variation (CV) and the Kendall's W determining the concordance of the evaluation were 5.06%-52.15% and 0.21-0.24 respectively. In the second round, the recovery rate was 93.75%; the Cr was 0.93; the mean was 3.93-4.93; the full mark ratios were 26.67%-93.33%; the Kendall's W was 0.14-0.31, the CV was 5.25%-23.61%. Via the two-round Delphi study, the scale that included 10 dimensions and 61 items has been improved. Ten dimensions are pre-hospital medical service, guidance, registration, waiting, diagnosis & treatment, paying, inspection & assay, medicine receiving, therapy/injection/transfusion and global evaluation. It was concluded that Chinese scholars have paid high attention to human caring and outpatient experience. The experts have given high agreements about the dimensions which were established with Chinese outpatient process. The dimensions are different from the similar researches about outpatient experience study. In the future, it is necessary to survey the outpatients to test the construct validity, internal consistency reliability and others of the scale to improve the scale.


Assuntos
Técnica Delphi , Pacientes Ambulatoriais , Assistência ao Paciente , Competência Clínica , Humanos , Inquéritos e Questionários
5.
Zhongguo Zhong Yao Za Zhi ; 43(24): 4878-4883, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30717534

RESUMO

The chemical consituents from the stems and leaves of Psychotria serpens were separated and purified by column chromatographies with silica gel, ODS, Sephadex LH-20 and PR-HPLC. The structures of the isolated compounds were identified on the basis of physicochemical properties and spectroscopic analyses, as well as comparisons with the data reported in literature. 18 compounds were isolated from the 90% ethanol extract of the stems and leaves of P. serpens, which were identified as chrysin(1), acacetin(2), genkwanin(3), chrysoeriol(4), rhamnocitrin(5), isorhamnetin(6), tricin(7), jaceosidin(8), dillenetin(9), kumatakenin(10), ayanin(11), isosakuranetin(12), eriodictyol(13), homoeriodictyol(14), taxifolin(15), pomonic acid(16), fupenzic acid(17) and euscaphic acid(18). All compounds were isolated from the genus Psychotria for the first time.


Assuntos
Medicamentos de Ervas Chinesas , Psychotria , Folhas de Planta , Caules de Planta
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