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1.
Mol Psychiatry ; 28(3): 1219-1231, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36604604

RESUMO

ATP9A, a lipid flippase of the class II P4-ATPases, is involved in cellular vesicle trafficking. Its homozygous variants are linked to neurodevelopmental disorders in humans. However, its physiological function, the underlying mechanism as well as its pathophysiological relevance in humans and animals are still largely unknown. Here, we report two independent families in which the nonsense mutations c.433C>T/c.658C>T/c.983G>A (p. Arg145*/p. Arg220*/p. Trp328*) in ATP9A (NM_006045.3) cause autosomal recessive hypotonia, intellectual disability (ID) and attention deficit hyperactivity disorder (ADHD). Atp9a null mice show decreased muscle strength, memory deficits and hyperkinetic movement disorder, recapitulating the symptoms observed in patients. Abnormal neurite morphology and impaired synaptic transmission are found in the primary motor cortex and hippocampus of the Atp9a null mice. ATP9A is also required for maintaining neuronal neurite morphology and the viability of neural cells in vitro. It mainly localizes to endosomes and plays a pivotal role in endosomal recycling pathway by modulating small GTPase RAB5 and RAB11 activation. However, ATP9A pathogenic mutants have aberrant subcellular localization and cause abnormal endosomal recycling. These findings provide strong evidence that ATP9A deficiency leads to neurodevelopmental disorders and synaptic dysfunctions in both humans and mice, and establishes novel regulatory roles for ATP9A in RAB5 and RAB11 activity-dependent endosomal recycling pathway and neurological diseases.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Animais , Humanos , Camundongos , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Endossomos/metabolismo , Transporte Proteico , Proteínas rab5 de Ligação ao GTP/genética , Proteínas rab5 de Ligação ao GTP/metabolismo
2.
J Org Chem ; 88(18): 13102-13114, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37672638

RESUMO

A Lewis base-catalyzed intramolecular vinylogous aldol reaction of o-(allyloxy)phenyl ketoesters or o-(allylamino)phenyl ketoesters has been developed. This reaction provides ready access to 3-hydroxy-2,3-disubstituted dihydrobenzofurans and indolines in high yields with excellent chemoselectivity and diastereoselectivity. An acid-promoted dehydration of such products further extends the utility of the reaction to the synthesis of 2-alkenyl benzofurans and indoles.

3.
Org Biomol Chem ; 21(40): 8176-8181, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37786314

RESUMO

Herein, we report a facile synthesis of 5-(3-oxindolyl)oxazole derivatives via a sequential annulation and isomerisation reaction of 3-acylmethylidene oxindoles with in situ generated Huisgen zwitterions (HZs) from PPh3 and azodicarboxylates. This reaction exhibits good functional group tolerance with 30 examples of structurally diverse products prepared with moderate to good efficiencies (up to 88% yield), thus providing a generally applicable route to the biologically important 5-(3-indolyl)oxazole structural motifs. Key to the success of this sequential one-pot strategy is the utilization of DBU as a base to promote the isomerisation process of the corresponding intermediate annulation products.

4.
J Org Chem ; 87(24): 16707-16721, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36473167

RESUMO

Herein, we report a ring-opening/cyclization cascade reaction of spiro(nitrocyclopropane)oxindoles with in situ generated Huisgen zwitterions (HZs) from PPh3 and azodicarboxylates. This reaction provides an array of polyfunctionalized pyrazolo[3,4-b]indole derivatives in moderate-to-excellent yields and generally high stereoselectivities with a broad substrate scope. The annulation products obtained from di-tert-butyl azodicarboxylates can be readily transformed into aromatic-substituted pyrazolo[3,4-b]indoles in moderate yields upon treatment with trifluoroacetic acid, thus providing a new entry to this fused heterocycle skeleton. In terms of nitro-substituted donor-acceptor cyclopropane, this work significantly broadens the substrate scope for the annulation reaction of nitrocyclopropanes and HZs. The dual roles of the oxindole moiety in the ring opening of cyclopropane and a plausible mechanism for the cascade reaction are also discussed.


Assuntos
Indóis , Compostos de Espiro , Oxindóis , Ciclização , Estrutura Molecular , Ciclopropanos , Catálise
5.
Molecules ; 27(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36500263

RESUMO

Substituent effects on the ultraviolet absorption properties of 2,4-dihydroxy dibenzophenone were investigated experimentally. Nine compounds of 2,4-dihydroxy dibenzophenone with different substituents were prepared by a solvent-free reaction of benzoyl chloride. The maximum absorption wavelength (λmax) of these samples was measured, and their UV resistance properties in cotton fabric as well as in polyester were determined. The results show that the λmax is dependent on the substituents at the benzylidene ring, and both electron donating substituents and electron withdrawing substituents cause a bathochromic shift. The UV resistance of fabric increases with the increase in compound concentration. The dyeing rate of each compound on polyester was higher than that of cotton. On cotton fabric, the dyeing rate of 2,4-dihydroxybenzophenone was the highest, 77.8%. On polyester, that of 2,4-dihydroxy-4'-ethyl dibenzophenone was the highest, 84.1%. The study provides new insights into the effect of substituents on the properties of 2,4-dihydroxy dibenzophenone that are related to the whitening of cotton and polyester materials.


Assuntos
Corantes , Têxteis , Solventes , Elétrons , Poliésteres
7.
J Org Chem ; 84(19): 12490-12498, 2019 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-31512469

RESUMO

Phosphine-catalyzed chemoselective [2 + 2 + 2] and [3 + 2] annulations of γ-methyl allenoates with doubly activated olefins have been developed, which afford highly substituted cyclohexanes bearing five continuous stereogenic centers and cyclopentenes bearing three continuous stereogenic centers, respectively, in generally high yields with excellent diastereoselectivity. The [2 + 2 + 2] annulation represents an unprecedented reactivity pattern of γ-methyl allenoates with activated C═C bonds to access six-membered carbocycles. In addition, the study herein also evidences that the acidic protic additives such as benzoic acid can exert influence on chemoselectivity of phosphine-catalyzed annulation reactions involving allenoates.

8.
Org Biomol Chem ; 17(29): 6989-6993, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31298257

RESUMO

An asymmetric (4 + 1) annulation of α-nitro cinnamates with Morita-Baylis-Hillman (MBH) acetates catalyzed by α-isocupreine is reported. It provides chiral isoxazoline N-oxides in moderate to good yields with 88-99% ee, and represents the first catalytic asymmetric (4 + 1) annulation of activated nitroalkenes with in situ generated ammonium ylides. It also affords a practical and efficient access to chiral isoxazoline N-oxides.

9.
Molecules ; 24(24)2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31888142

RESUMO

Tri- or tetrasubstituted furans have been prepared from terminal activated olefins and acyl chlorides or anhydrides by a multicomponental convergent synthesis mode. Instead of stoichiometric nBu3P, only catalytic nBu3P or nBu3P=O is needed to furnish the furans in modest to excellent yields with a good functional group tolerance under the aid of reducing agent silane. This synthetic method features a silane-driven catalytic intramolecular Wittig reaction as a key annulation step and represents the first successful application of catalytic Wittig reaction in multicomponent cascade reaction.


Assuntos
Técnicas de Química Sintética , Furanos/síntese química , Fosfinas/química , Catálise , Furanos/química , Estrutura Molecular
10.
J Org Chem ; 82(20): 10997-11007, 2017 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-28956607

RESUMO

The reductive (1 + 4) annulation reaction of isatins and substituted nitroalkenes mediated by a trivalent phosphorus reagent has been realized for the first time, providing easy access to spirooxindolyl isoxazoline N-oxides in moderate to excellent yields with a flexible substrate scope. This reaction presumably proceeds through a Michael addition-intramolecular substitution sequence via active in situ generated Kukhtin-Ramirez zwitterions from isatins and P(NMe2)3. It is also demonstrated that the spirooxindolyl isoxazoline N-oxides can be readily converted into the corresponding isoxazolines in good yields.

11.
Chemistry ; 22(17): 5883-7, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-26919274

RESUMO

An unusual formal [1+4] annulation of α-dicarbonyl compounds with 1,1-dicyano-1,3-dienes has been realized, leading to facile syntheses of cyclopentenimines and cyclopentenones in a unique manner. Mechanistic investigation implies that this reaction takes place through a P(NMe2 )3 -mediated cyclopropanation followed by a base-catalyzed cyclopropane rearrangement. It therefore represents an unprecedented [1+4] annulation mode involving Kukhtin-Ramirez adducts.

12.
J Org Chem ; 81(11): 4690-700, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27166729

RESUMO

A phosphine-catalyzed (4 + 1) annulation reaction of o-hydroxyphenyl and o-aminophenyl ketones with ester-modified allylic carbonates has been developed, providing a facile and efficient method to synthesize functionalized 2,3-disubstituted dihydrobenzofurans and indolines. Under mild conditions and in the catalysis of PPh3 (20 mol %), the reactions of o-hydroxyphenyl or o-aminophenyl ketones readily furnish highly functionalized 3-hydroxy-2,3-disubstituted dihydrobenzofurans or 3-hydroxy-2,3-disubstituted indolines in 40-99% yields with generally high diastereoselectivity. To further expand the utility of this annulation reaction to the synthesis of functionalized benzofurans and indoles, the CuSO4-promoted chemical transformations of the annulation products have also been studied.

13.
Org Biomol Chem ; 13(17): 4869-78, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25765334

RESUMO

Novel spirooxindole-pyrazolines and spirobenzofuranone-pyrazolines have been synthesized in good to excellent yields via the annulation reactions of the corresponding 3-alkylideneoxindoles and 3-alkylidenebenzofuranones with Huisgen zwitterions. The preliminary bioassay demonstrated that some of the spiropyrazolines possess good in vitro fungicidal activity against several crop fungi at a concentration of 50 µg mL(-1).


Assuntos
Antifúngicos/farmacologia , Benzofuranos/farmacologia , Fungos/efeitos dos fármacos , Indóis/farmacologia , Pirazóis/farmacologia , Compostos de Espiro/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Benzofuranos/síntese química , Benzofuranos/química , Relação Dose-Resposta a Droga , Indóis/síntese química , Indóis/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxindóis , Pirazóis/síntese química , Pirazóis/química , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade
14.
Org Biomol Chem ; 13(2): 398-408, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25369534

RESUMO

Amine-catalyzed [2 + 2 + 2] annulations of one molecule of Morita-Baylis-Hillman (MBH) acetates 1 with two molecules of 2-(arylmethylidene)indane-1,3-diones 2 or methyleneindolinones 4 have been developed under very mild conditions, which produce multistereogenic dispirocyclohexanes 3 and 5, respectively, in moderate to excellent yields and good diastereoselectivity. This amine-catalyzed annulation constitutes a novel and efficient method for the construction of dispirocyclohexane motifs, and also showcases the divergent catalysis between amines and phosphines with regard to the corresponding phosphine-catalyzed [3 + 2] annulations.

15.
J Org Chem ; 79(21): 10709-15, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25333339

RESUMO

A P(NMe2)3-mediated reductive cyclopropanation reaction of α-keto esters or amides with isatin-derived alkenes has been developed, providing efficient and diastereoselective synthesis of highly functionalized spirocyclopropyl oxindoles bearing two all-carbon quaternary centers. This reaction also represents a complementary and nonmetal-involving protocol for the challenging cyclopropanation of electron-deficient alkenes.


Assuntos
Alcenos/química , Ciclopropanos/síntese química , Indóis/síntese química , Isatina/química , Ciclopropanos/química , Elétrons , Indóis/química , Estrutura Molecular , Oxindóis , Estereoisomerismo
16.
Bioorg Med Chem ; 22(1): 303-10, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24315190

RESUMO

Various estrogen analogs were synthesized and tested for binding to human ERα using a fluorescence polarization displacement assay. Binding affinity and orientation were also predicted using docking calculations. Docking was able to accurately predict relative binding affinity and orientation for estradiol, but only if a tightly bound water molecule bridging Arg394/Glu353 is present. Di-hydroxyl compounds sometimes bind in two orientations, which are flipped in terms of relative positioning of their hydroxyl groups. Di-hydroxyl compounds were predicted to bind with their aliphatic hydroxyl group interacting with His524 in ERα. One nonsteroid-based dihdroxyl compound was 1000-fold specific for ERß over ERα, and was also 25-fold specific for agonist ERß versus antagonist activity. Docking predictions suggest this specificity may be due to interaction of the aliphatic hydroxyl with His475 in the agonist form of ERß, versus with Thr299 in the antagonist form. But, the presence of this aliphatic hydroxyl is not required in all compounds, since mono-hydroxyl (phenolic) compounds bind ERα with high affinity, via hydroxyl hydrogen bonding interactions with the ERα Arg394/Glu353/water triad, and van der Waals interactions with the rest of the molecule.


Assuntos
Estradiol/química , Receptor alfa de Estrogênio/química , Radical Hidroxila/síntese química , Feminino , Humanos , Radical Hidroxila/química , Relação Estrutura-Atividade
17.
Front Plant Sci ; 15: 1391248, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39148621

RESUMO

Introduction: The bZIP genes (bZIPs) are essential in numerous biological processes, including development and stress responses. Despite extensive research on bZIPs in many plants, a comprehensive genome-wide analysis of bZIPs in garlic has yet to be undertaken. Methods: In this study, we identified and classified 64 AsbZIP genes (AsbZIPs) into 10 subfamilies. A systematic analysis of the evolutionary characteristics of these AsbZIPs, including chromosome location, gene structure, conserved motifs, and gene duplication, was conducted. Furthermore, we also examined the nucleotide diversity, cis-acting elements, and expression profiles of AsbZIPs in various tissues and under different abiotic stresses and hormone treatments. Results and Discussion: Our findings revealed that gene replication plays a crucial role in the expansion of AsbZIPs, with a minor genetic bottleneck observed during domestication. Moreover, the identification of cis-acting elements suggested potential associations of AsbZIPs with garlic development, hormone, and stress responses. Several AsbZIPs exhibited tissue-preferential and stress/hormone-responsive expression patterns. Additionally, Asa7G01972 and Asa7G01379 were notably differentially expressed under various stresses and hormone treatments. Subsequent yeast two-hybridization and yeast induction experiments validated their interactions with Asa1G01577, a homologue of ABI5, reinforcing their importance in hormone and abiotic stress responses. This study unveiled the characteristics of the AsbZIP superfamily and lays a solid foundation for further functional analysis of AsbZIP in garlic.

18.
Cell Death Dis ; 15(7): 483, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969650

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, and the expression and function of an uncharacterized protein RNF214 in HCC are still unknown. Phase separation has recently been observed to participate in the progression of HCC. In this study, we investigated the expression, function, and phase separation of RNF214 in HCC. We found that RNF214 was highly expressed in HCC and associated with poor prognosis. RNF214 functioned as an oncogene to promote the proliferation, migration, and metastasis of HCC. Mechanically, RNF214 underwent phase separation, and the coiled-coil (CC) domain of RNF214 mediated its phase separation. Furthermore, the CC domain was necessary for the oncogenic function of RNF214 in HCC. Taken together, our data favored that phase separation of RNF214 promoted the progression of HCC. RNF214 may be a potential biomarker and therapeutic target for HCC.


Assuntos
Carcinoma Hepatocelular , Proliferação de Células , Progressão da Doença , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Humanos , Linhagem Celular Tumoral , Animais , Movimento Celular/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Masculino , Camundongos Nus , Camundongos , Regulação Neoplásica da Expressão Gênica , Feminino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Separação de Fases
19.
J Org Chem ; 78(21): 10596-604, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24087883

RESUMO

A highly chemoselective phosphine-catalyzed Rauhut-Currier reaction between maleimides and enones has been realized under very mild conditions, affording the corresponding cross-coupling products in moderate to excellent yields. On the basis of this reaction, an efficient dual phosphine-mediated one-pot synthesis of bicyclic and polycyclic compounds containing a cyclopenta[c]pyrrole skeleton has been accordingly developed, which features a tandem sequence of intermolecular Rauhut-Currier reaction and intramolecular Wittig reaction.

20.
Nat Cardiovasc Res ; 2(8): 778-792, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39195969

RESUMO

Mitophagy is a major quality control pathway that removes unwanted or dysfunctional mitochondria and plays an essential role in vascular health. Here we show that MCM8 expression is significantly decreased in children with Kawasaki disease (KD) who developed coronary artery aneurysms. Mechanistically, we discovered that nitric oxide signaling promotes TRIM21-mediated MCM8 ubiquitination, which disrupts its interaction with MCM9 and promotes its cytosolic export. In the cytosol, MCM8 relocates to the mitochondria pore-forming proteins and promotes their ubiquitination by TRIM21. In addition, MCM8 directly recruits LC3 via its LC3-interacting region (LIR) motif and initiates mitophagy. This suppresses mitochondrial DNA-mediated activation of type I interferon via cGAS and STING. Mice that are deficient in Mcm8, Trim21 and Nos2 or reconstituted with the East-Asian-specific MCM8-P276 variant develop more severe coronary artery vasculopathy in the Lactobacillus casei extract-induced KD model. Collectively, the data suggest that MCM8 protects vascular health in the KD setting.


Assuntos
Modelos Animais de Doenças , Mitofagia , Síndrome de Linfonodos Mucocutâneos , Óxido Nítrico , Transdução de Sinais , Animais , Síndrome de Linfonodos Mucocutâneos/metabolismo , Síndrome de Linfonodos Mucocutâneos/genética , Síndrome de Linfonodos Mucocutâneos/patologia , Humanos , Óxido Nítrico/metabolismo , Camundongos Knockout , Camundongos , Masculino , Ubiquitinação , Camundongos Endogâmicos C57BL , Feminino , Proteínas de Manutenção de Minicromossomo/metabolismo , Proteínas de Manutenção de Minicromossomo/genética , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética
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