RESUMO
Benzofuran-fused derivatives display important and reliable therapeutic properties. Herein, we describe the synthesis of benzofuran-fused oxepines using aurones and crotonate-derived sulfonium salts via a [4 + 3] annulation reaction in the presence of Cs2CO3. This reaction proceeds under mild and operationally simple conditions. The synthetic utility of this approach was highlighted by several transformations, including the efficient synthesis of a novel tetracyclic fused benzofuran derivative.
RESUMO
A divergent reaction of indoline-derived azadienes with α-bromohydroxamates for the selective synthesis of spiro-indolinepyrrolidinones and indoline-fused diazepinones was disclosed. This reaction sequence involved an initial formation of five-membered spirocyclic products followed by an intramolecular ring-opening and ring expansion to produce seven-membered diazepinones. We demonstrated that controlling the reaction time could modulate the reaction pathway for formation of different molecular frameworks for the same set of substrates. Based on the experimental results, the reaction mechanism was also discussed and proposed to explain the phenomena observed in the process.
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A [3 + 3] annulation of 3-aryl-3-hydroxyisoindolinones for the efficient synthesis of isoindolinone-derived spiroisochromenes is reported. In this Rh(III)-catalyzed spirocyclization reaction, vinylene carbonate is used as the coupling partner and acts as a three-atom synthon (C-C-O) through the decarboxylation process. This atom-economic reaction worked efficiently under mild conditions via a C-H activation pathway. It is the first example where 3-aryl-3-hydroxyisoindolinones are used as the building blocks to construct spiroheterocycles.
RESUMO
An efficient copper-catalyzed cascade annulation of o-hydroxyphenyl propargylamines and pyrazolin-5-ones is described. This methodology leads to the rapid assembly of a series of valuable pyrano[2,3-c]pyrazoles with good yields across a wide range of substrates in a simple fashion. This novel reaction involves the formation of alkynyl ortho-quinone methides, a 1,4-conjugate addition, and a subsequent 6-endo cyclization process. The mechanistic elucidation is well supported by control experiment and literature precedents.
Assuntos
Pirazolonas , Catálise , Cobre , Pargilina/análogos & derivados , Propilaminas , PirazóisRESUMO
A series of shikonin analogs have been synthesized in a one-pot reaction of quinizarin with ß,γ-unsaturated aldehydes in MeOH under mild conditions and investigated for their cytotoxicity against four cancer cell lines and one normal cell line. The synthesized compounds were found to be cytotoxic against HeLa cells with no apparent toxicity against normal cell line. Further modification led to the discovery of a novel tetracyclic anthraquinone (4b/4b') with potent cytotoxic activities against cervical, breast and pancreatic cancer cell lines with no significant effect on the growth of the control mammary epithelial cell line MCF-10. The good cytotoxicity and selectivity of compound 4b/4b' suggest that it could be a promising lead for further optimization.
Assuntos
Antracenos/farmacologia , Antineoplásicos/farmacologia , Antracenos/síntese química , Antracenos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
The design and synthesis of dual aromatase inhibitors/selective estrogen receptor modulators (AI/SERMs) is an attractive strategy for the discovery of new breast cancer therapeutic agents. Previous efforts led to the preparation of norendoxifen (4) derivatives with dual aromatase inhibitory activity and estrogen receptor binding activity. In the present study, some of the structural features of the potent AI letrozole were incorporated into the lead compound (norendoxifen) to afford a series of new dual AI/SERM agents based on a symmetrical diphenylmethylene substructure that eliminates the problem of E,Z isomerization encountered with norendoxifen-based AI/SERMs. Compound 12d had good aromatase inhibitory activity (IC50=62.2nM) while also exhibiting good binding activity to both ER-α (EC50=72.1nM) and ER-ß (EC50=70.8nM). In addition, a new synthesis was devised for the preparation of norendoxifen and its analogues through a bis-Suzuki coupling strategy.
Assuntos
Inibidores da Aromatase/síntese química , Inibidores da Aromatase/farmacologia , Aromatase/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Estilbenos/síntese química , Estilbenos/farmacologia , Inibidores da Aromatase/química , Sítios de Ligação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Células MCF-7 , Estrutura Molecular , Ligação Proteica , Estilbenos/química , Relação Estrutura-AtividadeRESUMO
Central neuromedin U 2 receptor (NMU2R) plays important roles in the regulation of food intake and body weight. Identification of NMU2R agonists may lead to the development of pharmaceutical agents to treat obesity. Based on the structure of rutin, a typical flavonoid and one of the NMU2R agonists we previously identified from an in-house made natural product library, 30 flavonoid derivatives have been synthesized and screened on a cell-based reporter gene assay. A number of compounds were found to be selective and highly potent to NMU2R. For example, the EC50 value of compound NRA 4 is very close to that of NMU, the endogenous peptide ligand of NMU2R. Structure-activity relationship analysis revealed that a 3-hydroxyl group in ring C and a 2'-fluoride group in ring B were essential for this class of compounds to be active against NMU2R.
Assuntos
Flavonoides/química , Flavonoides/farmacologia , Receptores de Neurotransmissores/agonistas , Desenho de Fármacos , Flavonoides/síntese química , Humanos , Receptores de Neurotransmissores/metabolismo , Relação Estrutura-AtividadeRESUMO
A simple, efficient, and general α-prenylation approach for the synthesis of a variety of α-prenylated alcohols has been successfully developed. A wide range of α-prenylated alcohol derivatives could be obtained in good yields by highly α-regioselective zinc-mediated prenylation of various aldehydes and ketones with prenyl bromide at 120 °C in HMPA. By simply altering the reaciton solvent and temperature, the method allows the achievement of a highly notable opposite regiocontrol, providing the expected regiochemical product. The method provides a convenient route for the direct α-prenylation of carbonyl compounds in a highly α-regioselective manner using a cheap and convenient mediator. Two possible pathways are proposed to account for the formation of these synthetically difficult-to-obtain molecules.
Assuntos
Aldeídos/química , Cetonas/química , Prenilação , Zinco/química , Catálise , Estereoisomerismo , Especificidade por SubstratoRESUMO
The Rh(III)-catalyzed dual directing group assisted C-H activation/annulation of 3-arylisoxazolones with propargyl alcohols has been developed, which expands the application scope of isoxazolones in organic synthesis. This protocol also worked well with 3-aryl-1,4,2-dioxazol-5-ones to produce synthetically and biologically important 4-arylisoquinolones.
RESUMO
An unusual [2 + 3] cycloaddition of isatin azomethine imines (AIs) and in situ generated azaoxyallyl cations has been developed. It is the first example where AIs serve as the [C,O] 2-atom synthon in organic synthesis. This work not only reveals a new role of isatin AIs in cycloaddition reaction but also provides an efficient access to unprecedented spiroheterocycle compounds.
RESUMO
A novel cross 1,3-dipolar cycloaddition between azomethine imines with in situ generated nitrile oxides has been developed. This is the first example of employing a reaction partner containing two heteroatoms in the [3+3] cycloaddition involving azomethine imines. This strategy not only provides structurally diverse N,O-heterocycles but also greatly enriches the chemistry of azomethine imines and nitrile oxides.
RESUMO
Aim: Histone deacetylase (HDAC) is an attractive target for antitumor therapy. Therefore, the development of novel HDAC inhibitors is warranted. Materials & methods: A series of HDAC inhibitors based on N-hydroxycinnamamide fragment was designed as the clinically used belinostat analog using amide as the connecting unit. All target compounds were evaluated for their in vitro HDAC inhibitory activities and some selected compounds were tested for their antiproliferative activities. Conclusion: Among them, compound 7e showed an IC50 value of 11.5 nM in inhibiting the HDAC in a pan-HDAC assay, being the most active compound of the series.
Assuntos
Desenho de Fármacos , Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Sulfonamidas/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Inibidores de Histona Desacetilases/síntese química , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/química , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/químicaRESUMO
A series of hydroxyanthraquinones having an alkylating N-mustard pharmacophore at 1'-position were synthesized via a bioisostere approach to evaluate their cytotoxicity against four tumor cell lines (MDA-MB-231, HeLa, MCF-7 and A549). These compounds displayed significant in vitro cytotoxicity against MDA-MB-231 and MCF-7 cells, reflecting the excellent selectivity for the human breast cancer. Among them, compound 5k was the most cytotoxic with IC50 value of 0.263 nM and is more potent than DXR (IC50 = 0.294 nM) in inhibiting the growth of MCF-7 cells. The excellent cytotoxicity and good selectivity of compound 5k suggest that it could be a promising lead for further design and development of anticancer agents, especially for breast cancer.
Assuntos
Antraquinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Desenho de Fármacos , Compostos de Mostarda Nitrogenada/síntese química , Compostos de Mostarda Nitrogenada/farmacologia , Antraquinonas/síntese química , Antraquinonas/química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Células MCF-7 , Estrutura Molecular , Compostos de Mostarda Nitrogenada/química , Relação Estrutura-AtividadeRESUMO
A highly α-regioselective prenylation of imines has been successfully developed. The efficiency of this approach is confirmed by a wide range of imines including N- and C-aryl aldimines, N-alkyl aldimines, C-alkyl aldimines, and N- and C-aryl ketimines. The approach uses prenyl bromide as the prenyl source and inexpensive and convenient zinc as the mediator as well as environmentally benign 1,3-dimethyl-2-imidazolidinone (DMI) as the solvent.
RESUMO
A series of 2-substituted-1,4-bis(dimethylamino)-9,10-anthraquinone derivatives were synthesized and their in vitro antiproliferative activities against p388 mouse leukemic tumor cells were evaluated. In addition, the effect of substituents on the phenyl ring was investigated. Among the derivatives tested, seven showed a high antiproliferative effect and three showed a moderate effect. In addition, introduction of a series of substituted phenyl groups into 1,4-bis(dimethylamino)-9,10-anthraquinone at 2-position were shown to enhance its antiproliferative activity. The antiproliferative activity also increased upon substitution of the benzene ring by an electron donating group such as an amine or methoxyl group.
Assuntos
Antraquinonas/síntese química , Antraquinonas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Animais , Antraquinonas/química , Antraquinonas/uso terapêutico , Antraquinonas/toxicidade , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Leucemia/tratamento farmacológico , Camundongos , Fenóis/síntese química , Relação Estrutura-AtividadeRESUMO
In an effort to develop potent antiplatelet agents, a series of trihydroxychalcones was synthesized and screened in vitro for their inhibitory effects on washed rabbit platelet aggregation induced by arachidonic acid (100 microM) and collagen (10 microg/ml). Of five compounds with potent inhibitory effects on arachidonic acid- and collagen-induced platelet aggregation, compound 4e was found to be the most potent. The structure-activity relationships suggested that antiplatelet activity was governed to a greater extent by the substituent on B ring of the chalcone template, and most of the active compounds had methoxy or dimethoxy groups on B ring.