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1.
J Org Chem ; 88(6): 3499-3508, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36891880

RESUMO

Rh(III)-catalyzed C-H/N-H annulation and C-H allylation of phenylindazolones have been realized by employing 5-methylene-1,3-dioxan-2-one and 4-vinyl-1,3-dioxolan-2-one as scalable cross-coupling partners, delivering functionalized indazolone fused heterocycles and branched and linear allyl indazolones respectively in moderate to high yield. These divergent synthesis protocols showcase mild conditions, broad substrate scope, and high functional-group compatibility. In addition, scale-up synthesis and preliminary mechanistic exploratory were also accomplished.

2.
J Org Chem ; 88(9): 5512-5519, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37011236

RESUMO

The indole-substituted trifluoromethyl sulfonium ylide has been developed via Cp*Rh(III)-catalyzed diazo-carbenoid addition to trifluoromethylthioether and is the first example of an Rh(III)-catalyzed diazo-carbenoid addition reaction with trifluoromethylthioether. Several kinds of indole-substituted trifluoromethyl sulfonium ylide were constructed under mild reaction conditions. The reported method exhibited high functional group compatibility and broad substrate scope. In addition, the protocol was found to be complementary to the method disclosed by a Rh(II) catalyst.

3.
Org Biomol Chem ; 20(25): 5055-5059, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35695281

RESUMO

Herein, we report a Rh(III)-catalyzed C4-selective activation of indoles by using iodonium ylides as carbene precursors. This protocol proceeded under redox neutral reaction conditions and provided important coupling products with good tolerance of functional groups and high yields. In addition, one-pot synthesis and scale-up and mechanistic studies were also conducted.


Assuntos
Ródio , Catálise , Indóis , Oxirredução
4.
Org Biomol Chem ; 20(3): 565-569, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-34985096

RESUMO

A thioether directed acyloxylation of arenes has been realized via Cp*Rh(III)-catalyzed C-H activation and subsequent coupling with carboxylic acids. This new method showed high functional group compatibility and broad substrate scope. Primary mechanistic studies have been conducted and a tentative reaction mechanism was proposed. It represents the first example of a thioether-directed Cp*Rh(III)-catalyzed C(sp2)-H acyloxylation reaction.

5.
J Org Chem ; 86(23): 17063-17070, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34797073

RESUMO

A tandem rhodium(III)-catalyzed system was established to access 3,4-dihydroisoquinolin-1(2H)-one by coupling of N-methoxy-3-methylbenzamide with 2-methylidenetrimethylene carbonate. This one-pot synthesis protocol processed smoothly under mild reaction conditions. Moreover, a total of 28 examples, broad substrate scope, and high functional-group compatibility were observed. Preliminary mechanism studies were also conducted and demonstrated that the rhodium(III) catalyst played a vital role in the C-H-allylation and N-alkylation cyclization process.


Assuntos
Ródio , Alquilação , Carbonatos , Catálise , Ciclização
6.
Org Biomol Chem ; 19(5): 993-997, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33443262

RESUMO

An efficient Rh(iii)-catalyzed C-H oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols by merging tandem C-H and C-C cleavage was developed. This transformation features mild reaction conditions, high regioselectivity, and excellent functional group compatibility. The resulting ß-aryl ketone derivatives can be readily transformed into 7-azaindole-containing π-extended polycyclic heteroarenes.

7.
Org Biomol Chem ; 19(5): 1155, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33521805

RESUMO

Correction for 'Rhodium(iii)-catalyzed oxidative alkylation of N-aryl-7-azaindoles with cyclopropanols' by Jidan Liu et al., Org. Biomol. Chem., 2021, DOI: .

8.
Org Biomol Chem ; 19(39): 8487-8491, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34545904

RESUMO

An efficient and practical approach for the synthesis of medicinally important acridones was developed from anthranils and commercially available arylboronic acids by a tandem copper(I)-catalyzed electrophilic amination/Ag(I)-mediated oxidative annulation strategy. This new and straightforward protocol displayed a broad substrate scope (25 examples) and high functional group tolerance. What's more, a possible mechanistic proposal was also presented.


Assuntos
Cobre
9.
Bioorg Med Chem Lett ; 30(4): 126925, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901379

RESUMO

A series of novel indole-pyrazoline hybrid derivatives were designed, synthesized, and evaluated for topoisomerase 1 (Top1) inhibitory activity. Top1-mediated relaxation assays showed that our synthesized compounds had variable Top1 inhibitory activity. Among these compounds, 3-(5-(naphthalen-1-yl)-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl)-1-(phenylsulfonyl)-1H-indole (6n) was found to be a strong Top1 inhibitor with better inhibitory activity than CPT and hit compounds. Our further experiments rationalized the mode of action for this new type of inhibitors, which showed no significant binding to supercoiled DNA.


Assuntos
DNA Topoisomerases Tipo I/química , Indóis/química , Pirazóis/química , Inibidores da Topoisomerase I/síntese química , Sítios de Ligação , DNA Topoisomerases Tipo I/metabolismo , DNA Super-Helicoidal/química , DNA Super-Helicoidal/metabolismo , Desenho de Fármacos , Humanos , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase I/metabolismo
10.
Angew Chem Int Ed Engl ; 57(40): 13096-13100, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30252190

RESUMO

A cobalt-catalyzed decarboxylative Negishi coupling reaction of redox-active aliphatic esters with organozinc reagents was developed. The method enabled efficient alkyl-aryl, alkyl-alkenyl, and alkyl-alkynyl coupling reactions under mild reaction conditions with no external ligand or additive needed. The success of an in situ activation protocol and the facile synthesis of the drug molecule (±)-preclamol highlight the synthetic potential of this method. Mechanistic studies indicated that a radical mechanism is involved.

11.
J Am Chem Soc ; 139(9): 3537-3545, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28177234

RESUMO

Fluorinated heterocycles play an important role in pharmaceutical and agrochemical industries. Herein, we report on the synthesis of four types of fluorinated heterocycles via rhodium(III)-catalyzed C-H activation of arenes/alkenes and versatile coupling with 2,2-difluorovinyl tosylate. With N-OMe benzamide being a directing group (DG), the reaction delivered a monofluorinated alkene with the retention of the tosylate functionality. Subsequent one-pot acid treatment allowed the efficient synthesis of 4-fluoroisoquinolin-1(2H)-ones and 5-fluoropyridin-2(1H)-ones. When N-OPiv benzamides were used, however, [4 + 2] cyclization occurred to provide gem-difluorinated dihydroisoquinolin-1(2H)-ones. Synthetic applications have been demonstrated and the ready availability of both the arene and the coupling partner highlighted the synthetic potentials of these protocols. Mechanistically, these two processes share a common process involving N-H deprotonation, C-H activation, and olefin insertion to form a 7-membered rhodacycle. Thereafter, different reaction pathways featuring ß-F elimination and C-N bond formation are followed on the basis of density functional theory (DFT) studies. These two pathways are DG-dependent and led to the open chain and cyclization products, respectively. The mechanistic rationale was supported by detailed DFT studies. In particular, the origins of the intriguing selectivity in the competing ß-F elimination versus C-N bond formation were elucidated. It was found that ß-F elimination is a facile event and proceeds via a syn-coplanar transition state with a low energy barrier. The C-N bond formation proceeds via a facile migratory insertion of the Rh-C(alkyl) into the Rh(V) amido species. In both reactions, the migratory insertion of the alkene is turnover-limiting, which stays in good agreement with the experimental studies.

12.
BMC Cardiovasc Disord ; 16: 82, 2016 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-27154403

RESUMO

BACKGROUND: Recent studies have shown Growth differentiation factor-15 (GDF-15) that is a member of the transforming growth factor ß (TGF-ß) superfamily might be a potential predictive cytokine for the prognosis of Acute coronary syndrome (ACS). However, there are discrepancies in these studies. METHODS: Publication searches of the PubMed/Medline and EMBASE databases were performed without any time or ethnicity restrictions. The inclusion and exclusion criteria, when clear, were addressed. Random effects models were used for all analyses. Publication bias was tested using funnel plots and the Egger test. RESULTS: We identified eight eligible studies that provided mortality data. Five of these studies provided recurrent myocardial infarction (MI) data. The maximal duration of follow-up ranged from 6 months to 6 years. A significant association was found between the patients with the highest and lowest GDF-15 levels (overall analyses) in terms of mortality (p < 0.00001; RR = 6.08; 95 % CI = 4.79-7.71) and recurrent MI (p < 0.00001; RR = 1.76; 95 % CI = 1.49-2.07). We also found significant associations between the subgroup analyses stratified by ACS types, cutoff points and follow-up durations (p < 0.001). The combined hazard ratio was high for GDF-15 to ACS (HR = 1.656, 95 % CI = 1.467-1.871). CONCLUSION: High plasma GDF-15 levels are associated with an increased risk of mortality and recurrent MI in patients with ACS.


Assuntos
Síndrome Coronariana Aguda/sangue , Fator 15 de Diferenciação de Crescimento/sangue , Infarto do Miocárdio/sangue , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/terapia , Biomarcadores/sangue , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/terapia , Razão de Chances , Valor Preditivo dos Testes , Prognóstico , Recidiva , Fatores de Risco , Fatores de Tempo , Regulação para Cima
13.
Zhonghua Xin Xue Guan Bing Za Zhi ; 43(3): 264-8, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-26269348

RESUMO

OBJECTIVE: To analyze the value of neutrophils/lymphocytes ratio (NLR) on predicting the cardiovascular events at hospital discharge and ≥ 12 months follow-up for patients with ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) by meta-analysis. METHODS: Both English and Chinese databases, including PubMed, EMBASE, Wanfang database from their reception to June 2014 were searched to identify randomized controlled studies or non-randomized controlled studies that reported relationship between NLR and the prognosis of patients with STEMI undergoing PCI.The Newcastle-OttawaScale (NOS) system was employed to assess the quality of literatures enrolled in this study. Two reviewers assessed the quality of each trial and extracted data independently. A standardized form and RevMan 5.2 software were used to extract information, and perform quantitative analysis, respectively. RESULTS: A total of 1 953 patients from 6 clinical trials were included in this meta-analysis. The risks of all-cause mortality (RR:0.29, 95% CI: 0.19-0.46, P<0.001), major adverse cardiac events (RR: 0.38, 95% CI: 0.31-0.46, P<0.001), nonfatal myocardial infarction (RR: 0.43, 95% CI: 0.28-0.67, P<0.001), stent thrombosis (RR: 0.32, 95% CI: 0.19-0.53, P<0.001), and TIMI flow after PCI procedure < 3 grade (RR: 0.34, 95% CI: 0.14-0.86, P = 0.020) were significantly lower in patients with NLR ≤ 3.30 compared patients with NLR > 3.30 at hospital discharge. During ≥ 12 months follow-up, the risks of death (RR: 0.33, 95% CI: 0.23-0.45, P<0.001), major adverse cardiac events (RR: 0.27, 95% CI: 0.20-0.35, P < 0.001) were significantly lower. Whereas nonfatal myocardial infarction was not significantly different (RR: 0.42, 95% CI: 0.05-3.45, P = 0.420) in patients with NLR ≤ 3.30 compared patients with NLR > 3.30. CONCLUSIONS: Results from this meta-analysis show that the NLR could predict short- and long-term prognosis in patients with STEMI undergoing PCI. This finding needs to be validated by large-scale clinical trials in the future.


Assuntos
Linfócitos , Infarto do Miocárdio , Neutrófilos , Humanos , Intervenção Coronária Percutânea , Prognóstico
14.
Chem Commun (Camb) ; 60(51): 6560-6563, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38845542

RESUMO

In this study, a Rh(III)-catalyzed C-H/N-H [4+2] annulation of oxadiazolones with iodonium ylides has been developed, which afforded a series of diverse fused-isoquinolines and fused-pyridines in moderate to high yields. These divergent synthesis protocols featured mild conditions, broad substrate scope, and functional-group compatibility. In addition, scale-up synthesis, related applications and preliminary mechanistic explorations were also accomplished.

15.
Org Lett ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995695

RESUMO

A metal-free cascade of α-acyloxylation/carboxamidation of I(III)/S(VI)-ylides, carboxylic acids, and isonitriles via a Passerini-like multicomponent reaction is reported. Unexpectedly, [3 + 1+1] cyclization involving I(III)/S(VI)-ylides and two molecules of ethyl isocyanoacetate was observed. The strategy allows for the synthesis of unsymmetrical α,α-disubstituted ketones and functionalized pyrroles with up to 99% yield and wide substrate compatibility. Notably, the procedure has been extended to the late-stage modification of drugs and natural products, offering an elegant complement to the classic Passerini reaction.

16.
Org Lett ; 26(27): 5811-5816, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38940397

RESUMO

A practical strategy for the construction of diverse phosphonyl and thiofunctionalized sulfoxonium ylides via controllable monofunctionalization of hybrid I(III)/S(VI) ylides is presented. This process allows efficient P-H insertion of I(III)/S(VI) ylides under Cu catalysis, enabling the synthesis of phosphonyl sulfoxonium ylides, whereas reaction with sulfur-containing reagents including AgSCF3, KSC(S)OR, and KSCN under mild conditions resulted in α-trifluoromethylthiolation, dithiocarbanation, and thiocyanation of sulfoxonium ylides accordingly. Of note, wide substrate compatibility (108 examples), excellent efficiency (up to 99% yield), gram-scale experiments, and various product derivatizations highlight the synthetic utility of this protocol.

17.
Chem Commun (Camb) ; 60(5): 598-601, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38099839

RESUMO

A new Cp*Rh(III)-catalyzed regioselective cyclization reaction of aromatic amides with allenes is reported. The use of allenyl derivatives bearing a directing-group assistant as a reaction promoter was the key to the success of this protocol. In this catalytic system, N-(pivaloyloxy)benzamide substrates react with allenes via Rh-σ-alkenyl intermediates, while N-(pivaloyloxy) indol substrates react via Rh-π-allyl intermediates. These reactions were characterized by mild reaction conditions, a broad substrate scope, and high functional-group compatibility to yield several high-value isoquinolinone and pyrimido[1,6-a]indol-1(2H)-one skeleton-containing compounds. The synthetic applications and primary mechanisms were also investigated.

18.
Org Lett ; 25(28): 5185-5190, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37439552

RESUMO

Cp*Rh(III)-catalyzed nitro-directed C-H alkylation/alkenylation of nitroarenes has been reported for the first time. This protocol is associated with the features of high efficiency, broad substrate scope, and good functional group compatibility. Additionally, gram-scale experiments and synthetic applications proved the practicability of the method. Moreover, preliminary mechanistic investigations consistently revealed C-H bond cleavage as the rate-limiting step.

19.
Org Lett ; 25(23): 4286-4291, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37265108

RESUMO

Two categories of tetrasubstituted phenols were prepared via the cycloaddition reaction of vinyl sulfoxonnium ylides with cyclopropenones in a switchable manner. Copper carbenoid was proposed as the active intermediate in the process of 2,3,4,5-tetrasubstituted phenols formation, while 2,3,5,6-tetrasubstituted phenols were generated via the direct [3 + 3] annulation of vinyl sulfoxonnium ylides with cyclopropenones under metal-free conditions. Further synthetic applications were also demonstrated.


Assuntos
Cobre , Metais , Catálise , Reação de Cicloadição
20.
Org Lett ; 25(28): 5179-5184, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37415264

RESUMO

Rh (III)-catalyzed dienylation and cyclopropylation of 1,2,3-benzotriazinones with alkylidenecyclopropanes (ACPs) has been achieved. Different from the previous reports of 1,2,3-benzotriazinones, the triazinone ring remained intact in this C-H bond functionlization reaction. Also, the denitrogenative cyclopropylation could also be realized by changing the reaction temperature. This protocol is featured with high E selectivity, wide substrate scope, and divergent structures of products.

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