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1.
J Org Chem ; 89(8): 5589-5605, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38576240

RESUMO

Diversity-oriented synthesis strategy for the efficient assembly of indole-fused polycyclic scaffolds via rhodium-catalyzed NH-indole-directed C-H coupling with propargylic alcohol derivatives in a regioselective manner was developed. Five 2-phenyl-1H-indole-embedded core skeletons were synthesized. In particular, three different indole-fused exo-olefin-containing polycycles were realized, which may be manipulated for further chemistry.

2.
J Org Chem ; 89(7): 4673-4683, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38478890

RESUMO

The cascade electrochemical C3-selective aerobic oxygenation of 2-substituted indoles and electrochemical [5 + 3] annulation with amidines through an undivided cell galvanostatic method employing molecular oxygen and "electricity" as green oxidants was developed. This protocol provides an efficient and direct approach to eight-membered benzo[1,3,5]triazocin-6(5H)-ones. Mechanistic studies suggested that two subsequent electrochemical processes both proceeded through radical pathways.

3.
Chemistry ; 29(69): e202302358, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37681747

RESUMO

We have developed an original blue-light mediated iron-catalyzed oxy-phosphinylation of activated alkenes by secondary phosphine oxides under air at room temperature. Various ß-ketophosphine oxides were then obtained in 43-97 % isolated yields. Control experiments revealed that radical process is involved in the mechanism.

4.
J Org Chem ; 88(21): 15198-15208, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37863844

RESUMO

A rhodaelectro-catalyzed C2-H selectively decarboxylative alkenylation of 3-carboxy-1H-indoles employing electricity as the traceless terminal oxidant has been accomplished. The weakly coordinating carboxyl group serves as the traceless directing groups. External oxidant-free in an undivided cell with constant current in aqueous solution ensures the decarboxylative C-H alkenylation to be viable and sustainable.

5.
Am J Dermatopathol ; 45(7): 492-494, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37249364

RESUMO

ABSTRACT: Cutaneous meningioma, characterized by ectopic meningothelial cells in the dermis or subcutis, is a rare neoplasm. Generally, the most common location for cutaneous meningioma is the scalp. We report a case of cutaneous meningioma presenting as soft, light red, atrophic, and smooth patches with central blue spots. On histological examination, the tumor consisted largely of epithelioid cells, whorls, nests, and syncytial sheets of meningothelial cells. HMB-45, Melan-A, and S100 were negative; epithelial membrane antigen and somatostatin receptor 2 were positive. Ultimately, histopathologic examination and immunohistochemistry results supported a diagnosis of cutaneous meningioma. In addition, dermal dysplasia was observed above the tumor, manifested by thinning of the dermis and loss of appendages. No abnormalities were found on brain magnetic resonance imaging. Cutaneous meningioma is an extremely rare tumor, and its manifestation as an atrophic patch is even rarer. There have been mainly clinical reports of cutaneous meningioma. This was a rare case of focal aplasia cutis congenita with cutaneous meningioma. For cutaneous meningioma to be diagnosed earlier, there needs to be greater public awareness about the condition.


Assuntos
Displasia Ectodérmica , Neoplasias Meníngeas , Meningioma , Neoplasias do Sistema Nervoso Periférico , Neoplasias Cutâneas , Humanos , Meningioma/patologia , Neoplasias Cutâneas/patologia , Displasia Ectodérmica/patologia , Neoplasias Meníngeas/patologia
6.
Angew Chem Int Ed Engl ; 62(34): e202305357, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37313642

RESUMO

Pristine fullerene C60 is an excellent electron transport material for state-of-the-art inverted structure perovskite solar cells (PSCs), but its low solubility leaves thermal evaporation as the only method for depositing it into a high-quality electron transport layer (ETL). To address this problem, we herein introduce a highly soluble bowl-shaped additive, corannulene, to assist in C60 -assembly into a smooth and compact film through the favorable bowl-ball interaction. Our results show that not only corannulene can dramatically enhance the film formability of C60 , it also plays a critical role in forming C60 -corannulene (CC) supramolecular species and in boosting intermolecular electron transport dynamics in the ETL. This strategy has allowed CC devices to deliver high power conversion efficiencies up to 21.69 %, which is the highest value among the PSCs based on the solution-processed-C60 (SP-C60 ) ETL. Moreover, the stability of the CC device is far superior to that of the C60 -only device because corannulene can retard and curb the spontaneous aggregation of C60 . This work establishes the bowl-assisted ball assembly strategy for developing low-cost and efficient SP-C60 ETLs with high promise for fully-SP PSCs.

7.
J Org Chem ; 87(16): 10967-10981, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35901234

RESUMO

Chemodivergent synthesis of indeno[1,2-b]indoles and isoindolo[2,1-a]indoles from the same starting materials involving radical cross-dehydrogenative couplings have been developed. Mn(OAc)3·2H2O selectively promoted an intramolecular radical C-H/C-H dehydrogenative coupling reaction to provide indeno[1,2-b]indoles, while an intramolecular radical C-H/N-H dehydrogenative coupling reaction could proceed via electrochemistry to deliver isoindolo[2,1-a]indoles. Plausible mechanisms of the chemodivergent reactions were proposed.

8.
J Org Chem ; 86(23): 16753-16763, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34756052

RESUMO

We report herein the facile synthesis of indole-fused six-, seven-, or eight-membered N,O-heterocycles through rhodium-catalyzed C-H acetoxylation/hydrolysis/annulation. The notable features of this method include C-H acetoxylation using NH-indole as the intrinsic directing group, high functional group compatibility, and construction of indole-fused medium-sized rings.


Assuntos
Ródio , Catálise , Ciclização , Hidrólise , Indóis
9.
Molecules ; 26(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34500762

RESUMO

Developing an efficient catalytic system using molecular oxygen as the oxidant for rhodium-catalyzed cross-dehydrogenative coupling remains highly desirable. Herein, rhodium-catalyzed oxidative annulation of 2- or 7-phenyl-1H-indoles with alkenes or alkynes to assemble valuable 6H-isoindolo[2,1-a]indoles, pyrrolo[3,2,1-de]phenanthridines, or indolo[2,1-a]isoquinolines using the atmospheric pressure of air as the sole oxidant enabled by quaternary ammonium salt has been accomplished. Mechanistic studies provided evidence for the fast intramolecular aza-Michael reaction and aerobic reoxidation of Rh(I)/Rh(III), facilitated by the addition of quaternary ammonium salt.

10.
J Org Chem ; 84(22): 14701-14711, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648520

RESUMO

An unprecedented rhodium-catalyzed regioselective C-H activation/1,8-diazabicyclo[5.4.0]undec-7-ene-catalyzed intramolecular amidation of 7-arylindoles with diazomalonates is described that provides a straightforward route to seven-membered azepino[3,2,1-hi]indoles in good to excellent yields in one pot. A wide range of functional groups, including F, OMe, NPh2, SiMe3, Cl, CN, CHO, COMe, CO2Me, CF3, and NO2, were all well-tolerated.

11.
Funct Integr Genomics ; 18(1): 67-78, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28956210

RESUMO

Drought is a major abiotic stress affecting crop productivity and quality. As a class of noncoding RNA, microRNA (miRNA) plays important roles in plant growth, development, and stress response. However, their response and roles in tomato drought stress is largely unknown. Here, by using high-throughput sequencing, we compared the miRNA profiles before and after drought treatment in two tomato genotypes: M82, a drought-sensitive cultivated tomato (Solanum lycopersicum), and IL2-5, a drought-tolerant introgression line derived from M82 and the tomato wild species S. pennellii (LA0716). A total of 108 conserved and 208 novel miRNAs were identified, among them, 32 and 68 were significantly changed in expression after stress. Further, 1936 putative target genes were predicted for those differentially-expressed miRNAs. Gene ontology and pathway analysis showed that many of the target genes were involved in stress resistance, such as genes in GO terms including response to stress, defense response, response to stimulus, phosphorylation, and signal transduction. Our results suggested that miRNAs play an essential role in the drought response of tomato. This work will help to further characterize specific miRNAs functioning in drought tolerance.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , MicroRNAs/genética , Análise de Sequência de RNA/métodos , Solanum lycopersicum/genética , Ontologia Genética
12.
14.
BMC Genomics ; 18(1): 481, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28651543

RESUMO

BACKGROUND: Abiotic stresses cause severe loss of crop production. Among them, drought is one of the most frequent environmental stresses, which limits crop growth, development and productivity. Plant drought tolerance is fine-tuned by a complex gene regulatory network. Understanding the molecular regulation of this polygenic trait is crucial for the eventual success to improve plant yield and quality. Recent studies have demonstrated that microRNAs play critical roles in plant drought tolerance. However, little is known about the microRNA in drought response of the model plant tomato. Here, we described the profiling of drought-responsive microRNA and mRNA in tomato using high-throughput next-generation sequencing. RESULTS: Drought stress was applied on the seedlings of M82, a drought-sensitive cultivated tomato genotype, and IL9-1, a drought-tolerant introgression line derived from the stress-resistant wild species Solanum pennellii LA0716 and M82. Under drought, IL9-1 performed superior than M82 regarding survival rate, H2O2 elimination and leaf turgor maintenance. A total of four small RNA and eight mRNA libraries were constructed and sequenced using Illumina sequencing technology. 105 conserved and 179 novel microRNAs were identified, among them, 54 and 98 were differentially expressed upon drought stress, respectively. The majority of the differentially-expressed conserved microRNAs was up-regulated in IL9-1 whereas down-regulated in M82. Under drought stress, 2714 and 1161 genes were found to be differentially expressed in M82 and IL9-1, respectively, and many of their homologues are involved in plant stress, such as genes encoding transcription factor and protein kinase. Various pathways involved in abiotic stress were revealed by Gene Ontology and pathway analysis. The mRNA sequencing results indicated that most of the target genes were regulated by their corresponding microRNAs, which suggested that microRNAs may play essential roles in the drought tolerance of tomato. CONCLUSION: In this study, numerous microRNAs and mRNAs involved in the drought response of tomato were identified using high-throughput sequencing, which will provide new insights into the complex regulatory network of plant adaption to drought stress. This work will also help to exploit new players functioning in plant drought-stress tolerance.


Assuntos
Secas , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/genética , Análise de Sequência de RNA , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Sequência Conservada , Genótipo , RNA Mensageiro/genética , Estresse Fisiológico/genética
15.
Org Biomol Chem ; 15(16): 3499-3506, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28387403

RESUMO

The palladium-catalyzed oxidative C-H olefination of uracils or caffeines with alkenes using an atmospheric pressure of molecular oxygen as the sole oxidant has been disclosed. This novel strategy offers an efficient and environmentally friendly method to biologically important C5-alkene uracil derivatives or C8-alkene caffeine derivatives.


Assuntos
Cafeína/química , Carbono/química , Hidrogênio/química , Oxidantes/química , Oxigênio/química , Paládio/química , Uracila/química , Catálise
16.
J Org Chem ; 81(24): 12135-12142, 2016 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-27978754

RESUMO

An efficient synthesis of 6H-isoindolo[2,1-a]indol-6-ones through rhodium-catalyzed NH-indole-directed C-H carbonylation of 2-arylindoles with carbon monoxide has been developed. Preliminary mechanistic studies revealed that this reaction proceeds via N-H bond cleavage and subsequent C-H bond cleavage. Reaction monitoring via ESI-MS was used to support the formation of five-membered rhodacycle species in the catalytic cycle.

17.
Opt Express ; 23(6): 8104-12, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25837148

RESUMO

We demonstrated the efficient guided laser action in a diode-pumped YAG/Nd:YAG/YAG ceramic planar waveguide produced by tape casting and vacuum sintering technology for the first time to the best of our knowledge. In the regime of continuous wave operation, a maximum output power of 840 mW corresponding to the slope efficiency of 65% was achieved. During passively Q-switched operation, by replacing the dichroic mirror with graphene-oxide based output coupler, we obtained the stable pulse trains with the shortest pulse duration of 179 ns at a pulse repetition rate of 930 kHz which resulted in the single pulse energy of 221 nJ.

18.
BMC Pharmacol Toxicol ; 25(1): 36, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943212

RESUMO

Chalcones and dihydrochalcones (DHCs) are important bioactive natural products (BNPs) isolated from traditional Chinese medicine. In this study, 13 chalcones were designed with the inspiration of Loureirin, a DHC extracted from Resina Draconis, and synthesized by classical Claisen-Schmidt reactions. Afterwards the reduction reactions were carried out to obtain the corresponding DHCs. Cytotoxicity assay indicated chalcones and DHCs possessed selective cytotoxicity against colorectal cancer (CRC) cells. The preliminary structure-activity relationships (SAR) of these compounds suggested the α, ß-unsaturated ketone of the chalcones were crucial for the anticancer activity. Interestingly, compounds 3d and 4c exhibited selective anticancer activity against CRC cell line HCT116 with IC50s of 8.4 and 17.9 µM but not normal cell. Moreover, 4c could also inhibit the migration and invasion of CRC cells. Mechanism investigations showed 4c could induce cell cycle G2/M arrest by regulating cell cycle-associated proteins and could also up-regulate Fas cell surface death receptor. The virtual docking further pointed out that compounds 3d and 4c could nicely bind to the Fas/FADD death domain complex (ID: 3EZQ). Furthermore, silencing of Fas significantly enhanced the proliferation of CRC cells and attenuated the cytotoxicity induced by 4c. These results suggested 4c exerted its anticancer activity possibly regulating cell cycle and Fas death receptor. In summary, this study investigated the anticancer activity and mechanism of Loureirin analogues in CRC, suggesting these compounds may warrant further investigation as promising anticancer drug candidates for the treatment of CRC.


Assuntos
Antineoplásicos , Chalconas , Neoplasias Colorretais , Receptor fas , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Chalconas/farmacologia , Chalconas/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Receptor fas/metabolismo , Relação Estrutura-Atividade , Células HCT116 , Simulação de Acoplamento Molecular , Movimento Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral
19.
J Dermatol ; 50(9): 1156-1161, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37350010

RESUMO

Psoriasis is an immune-mediated chronic, relapsing, inflammatory, systemic disease induced by a combination of genetics and environment. Currently, there are limited reports on the epidemiological and clinical characteristics of geriatric psoriatic patients in mainland China. This study analyzed the epidemiological characteristics, clinical features, and comorbidity rates of geriatric patients with psoriasis and evaluated the influence of age of onset on disease characteristics. This retrospective study enrolled 1259 geriatric patients with psoriasis in hospitals affiliated with the National Standardized Psoriasis Diagnosis and Treatment Center in China from September 2011 to July 2020 to analyze the epidemiological characteristics, clinical features, and prevalence of comorbidity in geriatric psoriasis. The cases were classified according to the age of onset into two groups to compare differences: early-onset psoriasis (EOP) and late-onset psoriasis (LOP). The mean age of geriatric patients with psoriasis was 67, with a 1.8:1 male-to-female ratio and 10.7% positive family history. The clinical manifestations of plaque psoriasis accounted for a high proportion (82.0%) and 85.1% of patients had moderate to severe disease. Overweight (27.8%), hypertension (18.0%), joint involvement (15.8%), diabetes (13.7%), and coronary heart disease (4.0%) were the first five common comorbidities. The LOP group had significantly more patients (79.9%) than the EOP group (20.1%). Positive family history was significantly associated with the EOP group (21.7%) than the LOP group (7.9%). The scalp (60.2%) was the most affected area, followed by the nails (25.3%), palmoplantar region (25.0%), and genitals (12.7%). This study analyzed the epidemiological and clinical characteristics of geriatric psoriasis in China and found that age of onset had no effect on disease characteristics or other comorbidities, except for toenail involvement, diabetes, and joint damage.


Assuntos
Diabetes Mellitus , Psoríase , Humanos , Masculino , Feminino , Idoso , Estudos Retrospectivos , Idade de Início , Psoríase/epidemiologia , Psoríase/diagnóstico , Comorbidade , Diabetes Mellitus/epidemiologia
20.
Psychol Res Behav Manag ; 16: 781-800, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36950311

RESUMO

Purpose: Procrastination has become a pervasive phenomenon in the workplace, yet knowledge of its antecedents remains limited. Therefore, this study explains when and why employees procrastinate. As procrastination is an individual intentional behavior to escape potential resource loss by taking actions to relax; this study regards procrastination as resource-protection behavior. Building on the conservation of resources (COR) theory, the purpose of the current study is to explore the direct impact of external situational factors (ie, stressor appraisals) and individual traits (ie, personality) and their interactive effect on workplace procrastination behavior. Participants and Methods: The study adopts a quantitative approach and uses two-wave data. Data was collected through the randomized cluster sampling technique and a structured questionnaire survey. The sample consisted of civil servants in an organization located in the Shandong province of China. Received 347 valid questionnaires representing an overall response rate of 87%. The theoretical model was tested through confirmatory factor analysis and regression analyses using Mplus 7.2. Results: The results show that hindrance stressor appraisal is positively related to procrastination, whereas challenge stressor appraisal is negatively related to procrastination. Neuroticism had a positive relationship with procrastination, while conscientiousness had a negative relationship with procrastination. Conscientiousness moderates the relationship between challenge stressor appraisal and procrastination such that the relationship is salient under high conscientiousness. Conclusion: Overall, our study suggests that procrastination is affected by personal traits and workplace stressor appraisals. This study makes potential contributions to employees' procrastination literature by and its understanding within the job procrastination knowledge base. Also, this study confirms the comprehensive reach and applicability of the COR theory developed by scholars such as Hobfoll (1989). In practically, the research benefits organizations by providing suggestions for managing employees' procrastination behavior.

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