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1.
Org Lett ; 26(19): 4104-4110, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38700913

RESUMO

Herein, a B(C6F5)3-catalyzed formal (n + 3) (n = 5 and 6) cycloaddition of bicyclo[1.1.0]butanes (BCBs) with imidazolidines/hexahydropyrimidines is described. The reaction provides a modular, atom-economical, and efficient strategy to two libraries of synthetically challenging medium-bridged rings, 2,5-diazabicyclo[5.1.1]nonanes and 2,6-diazabicyclo[6.1.1]decanes, in moderate to excellent yields. This reaction also features simple operation, mild reaction conditions, and broad substrate scope. A scale-up experiment and various synthetic transformations of products further highlight the synthetic utility.

2.
Chemistry ; 29(40): e202300562, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37052289

RESUMO

A novel approach to chemoselective synthesis of biologically important CF3 -subsituted pyrazolines was developed via a Lewis base catalyzed intermolecular triazene cycloaddition reaction of an array of terminal/internal alkenes with CF3 CHN2 . This strategy features a catalytic amount of 1,8-diazabicyclo[5.4.0]undec-7-ene, high yields (up to 95 %), wide substrate scope and excellent functional group tolerance (54 examples). Importantly, we preformed scaffold diversification of a panel of known pharmaceuticals, natural products, and bioactive heterocycles to generate the corresponding pyrazoline derivatives with potential broad bioactivities for further development.

3.
Org Biomol Chem ; 21(7): 1399-1403, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36723143

RESUMO

An N-heterocyclic carbene (NHC)-catalyzed [3 + 3] cycloaddition of α-bromoenals with nitroketene aminals or nitroketene N,S-acetals has been developed. This methodology provides an efficient strategy for the construction of valuable nitro-containing heterocyclic compounds. This protocol features mild reaction conditions, easily available starting materials, broad substrate scope and easy scalability.

4.
Org Lett ; 24(39): 7095-7100, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36154184

RESUMO

An unprecedented copper-catalyzed cascade reaction of 1,6-enynes with sulfoxonium ylides is reported, providing a series of structurally intriguing 2,3-disubstituted indolines bearing a conjugated dienone functionality at the 3-position in moderate to excellent yields with good chemo-, regio-, and diastereoselectivities under mild reaction conditions. Importantly, sulfoxonium-ylide-derived copper-carbene herein exhibits quite different reactivity from that of diazo copper-carbene. A rational mechanism, an initial ammonium ylide rather than allene formation, is proposed.

5.
Org Lett ; 24(35): 6443-6448, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36017905

RESUMO

Reported herein are the unprecedented copper-catalyzed formal [n + 1]/[n + 3] (n = 5, 6) cycloadditions of diazo compounds with imidazolidines/hexahydropyrimidines, thus providing a general, economical, and efficient route to construct different sized (six- to nine-membered) diaza-heterocycles in moderate to excellent yields under mild reaction conditions. This strategy features the use of copper catalyst to accomplish such diverse annulations and the utilization of imidazolidines/hexahydropyrimidines as stable 1,5-/1,6-dipoles.


Assuntos
Cobre , Imidazolidinas , Compostos Azo , Catálise , Reação de Cicloadição
6.
Int J Mol Sci ; 23(10)2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35628400

RESUMO

Infantile neuronal ceroid lipofuscinosis (INCL), the most severe form of neuronal ceroid lipofuscinoses, is caused by mutations in the lysosomal enzyme palmitoyl protein thioesterase 1 (PPT1). Typical symptoms of this disease include progressive psychomotor developmental retardation, visual failure, seizures, and premature death. Here, we investigated seizure activity and relevant pathological changes in PPT1 knock-in mice (PPT1 KI). The behavior studies in this study demonstrated that PPT1 KI mice had no significant seizure activity until 7 months of age, and local field potentials also displayed epileptiform activity at the same age. The expression levels of Iba-1 and CD68 demonstrated, by Western blot analysis, the inflammatory cytokine TNF-α content measured with enzyme-linked immunosorbent assay, and the number of microglia demonstrated by immunohistochemistry (IHC) were significantly increased at age of 7 months, all of which indicate microglia activation at an age of seizure onset. The increased expression of GFAP were seen at an earlier age of 4 months, and such an increase reached its peak at age of 6 months, indicating that astrocyte activation precedes microglia. The purinergic P2X7 receptor (P2X7R) is an ATP-sensitive ionic channel that is highly expressed in microglia and is fundamental to microglial activation, proliferation, cytokines release and epilepsy. We show that the ATP concentration in hippocampal tissue in PPT1 KI mice was increased using an enhanced ATP assay kit and demonstrated that the antagonist of P2X7R, A-438079, significantly reduced seizures in PPT1 KI mice. In contrast to glial cell activation and proliferation, a significant reduction in synaptic proteins GABAAR was seen in PPT1 KI mice. These results indicate that seizure in PPT1 KI mice may be associated with microglial activation involved in ATP-sensitive P2X7R signaling and impaired inhibitory neurotransmission.


Assuntos
Microglia , Lipofuscinoses Ceroides Neuronais , Tioléster Hidrolases , Trifosfato de Adenosina , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Camundongos Knockout , Microglia/metabolismo , Microglia/patologia , Lipofuscinoses Ceroides Neuronais/patologia , Convulsões/genética , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismo
7.
Chem Commun (Camb) ; 58(45): 6494-6497, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35574810

RESUMO

In this study, we designed and tested fluorescent probe zy-2 for specific and responsive imaging of pyruvate kinase M2 (PKM2), which can be excited by 419 nm light. A 17-fold enhancement in the responsive emission upon zy-2's binding to PKM2 was observed, imaging of which was successfully recorded in a time- and concentration-dependent manner in PKM2-positive cells. Thus, we obtained a responsive fluorescent probe for the specific and sensitive detection of PKM2, which is innovative in design and applicable to the detection of cancer cells.


Assuntos
Corantes Fluorescentes , Piruvato Quinase , Linhagem Celular Tumoral , Piruvato Quinase/metabolismo
8.
J Org Chem ; 87(9): 6247-6262, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35465667

RESUMO

A phenyliodine(III) diacetate-promoted/1,1,1,3,3,3-hexafluoroisopropanol-controlled dearomative spirocyclization of phenolic ketones was reported, providing two libraries of structurally interesting scaffolds, spirocyclohexadienonic ketals and their acetoxylated counterparts, in moderate to excellent yields under mild conditions. Control experiments unravel that the reaction proceeds through a spirocyclohexadienone-oxocarbenium cation species. In addition, an in situ-generated hypervalent iodine(III)-catalyzed version, as well as the late-stage transformation of products via conjugate additions, was also realized.


Assuntos
Iodo , Cetonas , Cátions , Fenóis
9.
J Org Chem ; 87(2): 1074-1085, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35057627

RESUMO

The reaction of vinylsulfonamides with donor-acceptor carbenes derived from α-aryldiazoesters, catalyzed by the tert-butyl glycine-derived dirhodium complex Rh2(S-4-Br-NTTL)4, has been reported. This method provides a variety of α-aryl-ß-aminocyclopropane carboxylic acid derivatives bearing one quaternary carbon stereogenic center vicinal to the amino-substituted carbon in high yields with excellent diastereo- and enantioselectivities. Vinylsulfonamides showed complementary advantages over the well-developed vinylamides or vinylcarbamates for this Rh(II)-catalyzed cyclopropanation strategy. Moreover, these conformationally restricted α-aryl-ß-aminocyclopropyl carboxylic acid derivatives can be readily incorporated into dipeptides.


Assuntos
Ácidos Carboxílicos , Glicina , Catálise , Estrutura Molecular , Estereoisomerismo
10.
J Org Chem ; 86(6): 4714-4732, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33667091

RESUMO

An unprecedented copper-catalyzed tandem reaction of 1,6-enynes with diazo compounds via a cross-coupling/[2 + 2] cycloaddition sequence was reported. A library of methylenecyclobutane-fused ring systems including cyclobuta[b]indolines, cyclobuta[b]benzofuran, benzo[b]cyclobuta[d]thiophene, and bicyclo[3.2.0] structures were obtained in moderate to excellent yields under very mild reaction conditions. The reaction exhibited high proximal-regioselectivity and diastereoselectivity. Moreover, 1,6-allenene has proven to be the key intermediate and proceeds via a thermally promoted [2 + 2] cycloaddition in the absence of copper catalyst.

11.
Org Biomol Chem ; 18(45): 9292-9299, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33164006

RESUMO

Under catalyst-free conditions, an efficient method to synthesize 2-pyridinylamides has been developed, and the protocol uses inexpensive and readily available 2-fluoropyridine and amidine derivatives as the starting materials. Simultaneously, the copper-catalysed approach to imidazopyridine derivatives has been established with high chemoselectivity and regiospecificity. The results suggest that the nitrogen-heterocycles containing iodide substituents can also be compatible for the reaction via the cascade Ullmann-type coupling, and the nucleophilic substitution reaction provides the target products in a one-pot manner.

12.
Org Lett ; 22(14): 5589-5593, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32588631

RESUMO

An unprecedented palladium(II)-catalyzed oxidative decarboxylative [2 + 2 + 1] annulation of cinnamic acids with alkynes has been developed for the synthesis of polysubstituted pentafulvenes. Ag2CO3 and DMSO are essential for the reaction. This protocol features readily available starting materials, a wide substrate scope, and moderate to excellent yields. Moreover, various significant frameworks can be easily obtained from the late-stage transformations of pentafulvenes via oxidation, reduction, and Scholl-type reaction.

13.
Org Lett ; 22(8): 3200-3204, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32267158

RESUMO

Palladium-catalyzed dearomative [2+2+1] annulations of aryl ethers with alkynes are reported via para-selective C-H functionalization, providing highly functionalized spirocyclohexadienones in moderate to excellent yields under mild reaction conditions. Importantly, mechanistic investigation indicated an unusual C-O bond cleavage was involved. Moreover, polyarylated naphthalenes could be obtained via oxidative [2+2+2] annulation by tuning aryl ethers from monomethoxybenzenes to polymethoxybenzenes under an identical catalytic system.

14.
J Org Chem ; 85(6): 4418-4429, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-32091906

RESUMO

A copper-catalyzed cascade reaction of diazo compounds with 1,n-allenynes (n = 6,7) was reported, which provides efficient access to various functionalized 3-azabicyclo[m.2.0] frameworks (m = 5,6) in moderate to excellent yields under mild reaction conditions. The reaction proceeds through intermolecular cross-coupling to form bisallene intermediates, followed by subsequent intramolecular [2+2] cycloaddition.

15.
Pharmacol Res ; 152: 104618, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31891789

RESUMO

Several decades have passed since resveratrol (RSV) was first identified in red wine. Researchers have reported the pleiotropic anti-oxidant, anti-inflammatory, anti-cancer, anti-aging, and neuronal protective effects of resveratrol and its glycosylated derivative. However, few studies have distinguished the minute differences in the properties between resveratrol and its glycosylated derivative in terms of synaptic plasticity. As an abundant natural product of glycosylated resveratrol, the derivative 2,3,4',5-tetrahydroxystilbene-2-O-ß-d-glucoside (TSG) has been determined to be a better option for long-term potentiation (LTP) in the hippocampus under physiological and pathological conditions than resveratrol. TSG, as well as its parent molecule RSV, could elicit early-LTP and recover fast excitatory postsynaptic potentials (EPSPs) in the hippocampus. Using various modalities, including pre- and post-whole-cell patch clamping techniques in the calyx of Held, pharmacological inhibition of the N-methyl-d-aspartic acid receptor (NMDAr) and the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAr) as well as protein kinase C (PKC) activation, we demonstrated that TSG, unlike RSV, could merely promote NMDA-mediated EPSC via PKCß cascade. Our results provide new knowledge that glycosylation of resveratrol could significantly improve its specificity in promoting sole NMDAr mediation of EPSPs, in addition to improving solubility and resistance against oxidation in vivo. These observations could contribute to further exploration of pharmaceutical evaluation of glycosylated stilbene in the future.


Assuntos
Glucosídeos/farmacologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Hipocampo/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase C beta/fisiologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/fisiologia
16.
Org Lett ; 21(23): 9559-9563, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31710502

RESUMO

An unprecedented copper-catalyzed tandem cross-coupling/[2 + 2] cycloaddition of 1,6-allenynes with diazo compounds was reported, chemo- and regioselectively providing 3-azabicyclo[5.2.0] frameworks in moderate to excellent yields under mild reaction conditions. Moreover, the products readily convert to highly functionalized quinolines via oxidative radical rearrangement.

17.
J Cell Mol Med ; 23(9): 6512-6518, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31270934

RESUMO

Genome-wide association studies have confirmed that schizophrenia is an inheritable multiple-gene mental disorder. Longitudinal studies about depression, first episode psychosis (FEP) and acute psychotic relapse have mostly searched for brain imaging biomarkers and inflammatory markers from the blood. However, to the best of our knowledge, the association between enzymatic activities with diagnosis or prediction of treatment response in people with schizophrenia has barely been validated. Under the Longitudinal Study of National Mental Health Work Plan (2015-2020), we have studied a subsample of approximately 36 individuals from the cohort with data on palmitoyl-protein thioesterase-1 enzymatic activity from FEP and performed a bivariate correlation analysis with psychiatric assessment scores. After adjusting for sex, age, body mass index (BMI) and total serum protein, our data demonstrated that PPT1 enzymatic activity is significantly associated with schizophrenia and its Positive and Negative Syndrome Scale (PANSS) scores. This longitudinal study compared the PPT1 enzymatic activity in FEP schizophrenia patients and healthy volunteers, and the former exhibited a significant 1.5-fold increase in PPT1 enzymatic levels (1.79 mmol/L/h/mL, and 1.18 mmol/L/h/mL; P < 0.05; 95% CI, 2.3-2.9 and 1.4-1.8). The higher PPT1 enzymatic levels in FEP schizophrenia patients were positively associated with larger PANSS scaling scores (r = 0.32, P = 0.0079 for positive scaling; r = 0.41, P = 0.0006 for negative scaling; r = 0.45, P = 0.0001 for general scaling; and r = 0.34, P = 0.0048 for PNASS-S scaling). Higher enzymatic PPT1 in FEP schizophrenia patients is significantly associated with increased PANSS scaling values, indicating more serious rates of developing psychosis. Enzymatic activity of PPT1 may provide an important new view for schizophrenia disorders.


Assuntos
Esquizofrenia/sangue , Esquizofrenia/metabolismo , Tioléster Hidrolases/sangue , Tioléster Hidrolases/metabolismo , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Coortes , Depressão/sangue , Depressão/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/sangue , Transtornos Psicóticos/metabolismo , Adulto Jovem
18.
Org Lett ; 21(13): 5167-5171, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31247798

RESUMO

Rhodium-catalyzed regiodivergent [3 + 2] and [5 + 2] cycloadditions of quinolinium ylides with alkynes are reported, providing highly functionalized five-membered indolizine derivatives and seven-membered 1,4-oxazepine compounds, respectively, in moderate to excellent yields under mild reaction conditions. Importantly, quinolinium ylides are derived from donor-acceptor diazo compounds, and different types of donor-acceptor diazo compounds exhibit distinct selectivity and reactivity for the reactions. The [3 + 2] cycloadditions involve an unusual 1,3-ester migration process.

19.
J Clin Psychopharmacol ; 39(3): 214-219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30946280

RESUMO

BACKGROUND: Olanzapine, a commonly used second-generation antipsychotic, causes severe metabolic adverse effects, such as elevated blood glucose and insulin resistance (IR). Previous studies have proposed that overexpression of CD36, GGPPS, PTP-1B, GRK2, and adipose triglyceride lipase may contribute to the development of metabolic syndrome, and Pueraria could eliminate the metabolic adverse effects. The study aimed to investigate the association between olanzapine-associated IR and IR-related proteins (IRRPs) and determine the role of Pueraria in protection against the metabolic adverse effects of olanzapine. METHODS: The expression levels of IRRPs were examined in schizophrenia patients and rat models with long-term olanzapine treatment. The efficacy of Pueraria on anti-IR by reducing the expression of IRRPs was comprehensively evaluated. RESULTS: Our study demonstrated that in schizophrenia patients chronically treated with olanzapine, the expression levels of IRRPs in patients with a high IR index significantly increased, and these phenomena were further confirmed in a rat model. The expression levels of IRRPs were reduced significantly in Pueraria-treated IR rat models. The body weight, blood glucose, and IR index were restored to levels similar to those of normal controls. CONCLUSIONS: The IRRPs are closely related to IR induced by olanzapine, and Pueraria could interfere with olanzapine-associated IR and revert overexpressed IRRPs. These findings suggest that IRRPs are key players in olanzapine-associated IR and that Pueraria has potential as a clinical drug to prevent the metabolic adverse effects of olanzapine, further improving compliance of schizophrenia patients.


Assuntos
Resistência à Insulina , Olanzapina/efeitos adversos , Extratos Vegetais/farmacologia , Pueraria/química , Adulto , Animais , Antipsicóticos/administração & dosagem , Antipsicóticos/efeitos adversos , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina/administração & dosagem , Ratos , Esquizofrenia/tratamento farmacológico , Fatores de Tempo
20.
Sci Rep ; 9(1): 1582, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30733507

RESUMO

Olanzapine is a second-generation anti-psychotic drug used to prevent neuroinflammation in patients with schizophrenia. However, the long-term administration of olanzapine leads to insulin resistance (IR); the mechanisms of this effect remains poorly understood. Using cellular and rodent models of IR induced by olanzapine, we found that chronic olanzapine treatment induces differential inflammatory cytokine reactions in peripheral adipose and the central nervous system. Long-term treatment of olanzapine caused metabolic symptoms, including IR, by markedly elevating the plasma levels of pro-inflammatory cytokines, including IL-1ß, IL-6, IL-8 and TNFα; these findings are consistent with observations from schizophrenia patients chronically treated with olanzapine. Our observations of differential inflammatory cytokine responses in white adipose tissues from the prefrontal cortex in the brain indicated cell type-specific effects of the drug. These cytokines induced IR by activating NF-kB through the suppression of IkBα. Functional blockade of the components p50/p65 of NF-kB rescued olanzapine-induced IR in NIH-3T3 L1-derived adipocytes. Our findings demonstrate that olanzapine induces inflammatory cytokine reactions in peripheral tissues without adversely affecting the central nervous system and suggest that chronic olanzapine treatment of schizophrenia patients may cause inflammation-mediated IR with minimal or no adverse effects in the brain.


Assuntos
Antipsicóticos/efeitos adversos , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Resistência à Insulina , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Olanzapina/efeitos adversos , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adulto , Animais , Antipsicóticos/administração & dosagem , Glicemia , Modelos Animais de Doenças , Duração da Terapia , Feminino , Transportador de Glucose Tipo 4/metabolismo , Humanos , Masculino , Camundongos , Modelos Biológicos , NF-kappa B/metabolismo , Olanzapina/administração & dosagem , Ratos , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Adulto Jovem
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