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1.
Chem Commun (Camb) ; 56(9): 1357-1360, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31904755

RESUMO

A phosphoryl radical-initiated Atherton-Todd-type reaction using air as the radical initiator and CHCl3 as the halogenating reagent for the phosphorylation of alcohols, phenols, and amines has been developed. This novel transformation provides a highly efficient route to important phosphinates, phosphinic amides, and phosphoramidates in up to 99% yield with a broad substrate scope under very mild conditions (48 examples).

2.
J Org Chem ; 84(22): 14949-14956, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31622097

RESUMO

A direct and practical metal-free N-H phosphorylation has been achieved via the TBHP/NH4I-mediated cross-dehydrogenative coupling (CDC) reactions between imines/imidates and P(O)H compounds. This transformation provides an efficient synthetic route to the construction of P-N bonds with good functional group compatibility, leading to the formation of N-phosphorylimines and N-phosphorylimidates in up to 95% yield (33 examples) under mild conditions.

3.
Org Biomol Chem ; 16(22): 4086-4089, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29790550

RESUMO

An efficient halogen-free Cs2CO3-promoted methylene insertion into disulfide bonds has been achieved using acetone as a methylene source under mild conditions. This method provides a convenient and practical route to dithioacetals in up to 96% yield with good functional group compatibility.

4.
Org Biomol Chem ; 16(10): 1713-1719, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29451569

RESUMO

A highly efficient sulfonylation of thiols has been achieved through the metal-free NaI/TBHP-mediated cross-coupling of sulfonyl hydrazides and thiols at room temperature. This method provides a convenient and practical route to thiosulfonates in 84-99% yields (39 examples) with wide functional group compatibility.

5.
Yao Xue Xue Bao ; 39(10): 831-5, 2004 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-15700826

RESUMO

AIM: To detect the hepatotoxic pyrrolizidine alkaloids (HPA) in the genus Ligularia Cass.. METHODS: The alkaloid extracts of Ligularia plant materials were detected and analyzed by the method of combination of TLC, and LC/MSn. RESULTS: Among 22 species of Ligularia Cass., HPA were detected in 18 species with LC/MSn, and no HPA was detected in the remaining 4 species. CONCLUSION: HPA was first detected with LC/MSn in L. tongelensis and other 15 species of Ligularia Cass.; HPA from these plants should be isolated, separated and identified and it is necessary to study the activities and toxicities of the HPA. The types and kinds of HPA from different species and sources are different, they should be detected separately.


Assuntos
Asteraceae/química , Plantas Medicinais/química , Alcaloides de Pirrolizidina/análise , Asteraceae/classificação , Cromatografia em Camada Fina , Estrutura Molecular , Alcaloides de Pirrolizidina/química , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray
6.
Zhongguo Zhong Yao Za Zhi ; 29(5): 399-401, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15706885

RESUMO

OBJECTIVE: To study the resource and the quality of wild Corydalis yanhusuo distributed in China. METHOD: Distribution was observed and samples of wild C. yanhusuo were collected and qualities were evaluated by determining six main alkaloids contained in the samples. RESULT: The main distribution of wild Corydalis yanhusuo was in the hills around middle and lower reaches of Yangtze River. Its distributive areas were continuously decreasing. The alkaloids contents in the samples varied among different populations. CONCLUSION: The alkaloids contents in wild populations of C. yanhusuo are diverse. The main kinds of alkaloids in some wild populations are higher than cultivated ones, which are valuable for breeding. The wild C. yanhusuo propagate well, however they are endangered due to environment problem, and should be protected.


Assuntos
Alcaloides de Berberina/análise , Conservação dos Recursos Naturais , Corydalis , Plantas Medicinais , Aporfinas/análise , China , Corydalis/química , Ecossistema , Farmacognosia , Plantas Medicinais/química , Controle de Qualidade , Rizoma/química
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