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1.
Chemistry ; : e202402475, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169448

RESUMEN

Herein, we report a facile and efficient deuteration degree controllable method for the preparation of aryl deuteromethyl ethers through dual photoredox and thiol catalysis using phenols as the starting materials and inexpensive D2O and CDCl3 as the deuterium sources. All aryl d1, d2, and d3 deuteromethyl ethers can be precisely prepared with good to excellent yields and deuteration ratios. The reaction operates under mild conditions without the need for high temperatures or high loading of transition metal catalysts, and a wide range of functional groups are well tolerated.

2.
Org Biomol Chem ; 22(18): 3592-3596, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38624160

RESUMEN

Herein, we describe an efficient method for the synthesis of alkenylphosphine oxides via a Tf2O promoted addition-elimination process. Various diarylphosphine oxides and alkylarylphosphine oxides react with ketones smoothly and produce alkenylphosphine oxides in moderate to excellent yields with abundant functional group compatibility. In addition, several transformations and applications of the product also demonstrate the potential value of the methodology.

3.
J Org Chem ; 87(7): 4918-4925, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35316060

RESUMEN

In recent years, methyl formate has received considerable attention as an ideal and green C1 building block to synthesize carboxylic esters. However, examples of a one-step route to esters with one-carbon elongation using methyl formate as a source of methoxycarbonyl radical are still rare. Herein, we present peroxide-induced radical carbonylation of N-(2-methylallyl)benzamides with methyl formate as the precursor of methoxycarbonyl radical and RuCl3 as catalyst, affording a series of biologically valuable 4-[(methoxycarbonyl)methyl]-3,4-dihydroisoquinolinones with good tolerance and insensitivity to moisture in one pot under simple and mild conditions.


Asunto(s)
Alquenos , Formiatos , Catálisis , Esterificación , Ésteres
4.
World J Surg Oncol ; 18(1): 268, 2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33066779

RESUMEN

BACKGROUND: Breast cancer subtypes are statistically associated with prognosis. The search for markers of breast tumor heterogeneity and the development of precision medicine for patients are the current focuses of the field. METHODS: We used a bioinformatic approach to identify key disease-causing genes unique to the luminal A and basal-like subtypes of breast cancer. First, we retrieved gene expression data for luminal A breast cancer, basal-like breast cancer, and normal breast tissue samples from The Cancer Genome Atlas database. The differentially expressed genes unique to the 2 breast cancer subtypes were identified and subjected to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. We constructed protein-protein interaction networks of the differentially expressed genes. Finally, we analyzed the key modules of the networks, which we combined with survival data to identify the unique cancer genes associated with each breast cancer subtype. RESULTS: We identified 1114 differentially expressed genes in luminal A breast cancer and 1042 differentially expressed genes in basal-like breast cancer, of which the subtypes shared 500. We observed 614 and 542 differentially expressed genes unique to luminal A and basal-like breast cancer, respectively. Through enrichment analyses, protein-protein interaction network analysis, and module mining, we identified 8 key differentially expressed genes unique to each subtype. Analysis of the gene expression data in the context of the survival data revealed that high expression of NMUR1 and NCAM1 in luminal A breast cancer statistically correlated with poor prognosis, whereas the low expression levels of CDC7, KIF18A, STIL, and CKS2 in basal-like breast cancer statistically correlated with poor prognosis. CONCLUSIONS: NMUR1 and NCAM1 are novel key disease-causing genes for luminal A breast cancer, and STIL is a novel key disease-causing gene for basal-like breast cancer. These genes are potential targets for clinical treatment.


Asunto(s)
Neoplasias de la Mama , Antígeno CD56/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Receptores de Neurotransmisores/genética , Neoplasias de la Mama/genética , Quinasas CDC2-CDC28 , Proteínas de Ciclo Celular , Biología Computacional , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Humanos , Cinesinas , Pronóstico , Mapas de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas
5.
J Am Chem Soc ; 139(13): 4611-4614, 2017 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-28263595

RESUMEN

Several variants of a nucleic acid binding motif (RRM1) of putative transcription factor hnRNP LL containing nucleobase amino acids at specific positions have been prepared and used to study binding affinity for the BCL2 i-motif DNA. Molecular modeling suggested a number of amino acids in RRM1 likely to be involved in interaction with the i-motif DNA, and His24 and Arg26 were chosen for modification based on their potential ability to interact with G14 of the i-motif DNA. Four nucleobase amino acids were introduced into RRM1 at one or both of positions 24 and 26. The introduction of cytosine nucleobase 2 into position 24 of RRM1 increased the affinity of the modified protein for the i-motif DNA, consistent with the possible Watson-Crick interaction of 2 and G14. In comparison, the introduction of uracil nucleobase 3 had a minimal effect on DNA affinity. Two structurally simplified nucleobase analogues (1 and 4) lacking both the N-1 and the 2-oxo substituents were also introduced in lieu of His24. Again, the RRM1 analogue containing 1 exhibited enhanced affinity for the i-motif DNA, while the protein analogue containing 4 bound less tightly to the DNA substrate. Finally, the modified protein containing 1 in lieu of Arg26 also bound to the i-motif DNA more strongly than the wild-type protein, but a protein containing 1 both at positions 24 and 26 bound to the DNA less strongly than wild type. The results support the idea of using nucleobase amino acids as protein constituents for controlling and enhancing DNA-protein interaction. Finally, modification of the i-motif DNA at G14 diminished RRM1-DNA interaction, as well as the ability of nucleobase amino acid 1 to stabilize RRM1-DNA interaction.


Asunto(s)
Aminoácidos/química , ADN/química , Proteínas Proto-Oncogénicas c-bcl-2/química , Sitios de Unión , Humanos , Modelos Moleculares , Estructura Molecular , Motivos de Nucleótidos
6.
ScientificWorldJournal ; 2014: 829614, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24959631

RESUMEN

In order to meet the demands of operation monitoring of large scale, autoscaling, and heterogeneous virtual resources in the existing cloud computing, a new method of live virtual machine (VM) migration detection algorithm based on the cellular neural networks (CNNs), is presented. Through analyzing the detection process, the parameter relationship of CNN is mapped as an optimization problem, in which improved particle swarm optimization algorithm based on bubble sort is used to solve the problem. Experimental results demonstrate that the proposed method can display the VM migration processing intuitively. Compared with the best fit heuristic algorithm, this approach reduces the processing time, and emerging evidence has indicated that this new approach is affordable to parallelism and analog very large scale integration (VLSI) implementation allowing the VM migration detection to be performed better.


Asunto(s)
Inteligencia Artificial , Redes Neurales de la Computación , Algoritmos
7.
Fundam Res ; 4(3): 603-610, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38933194

RESUMEN

A magnetorheological self-centering brace (MR-SCB) has been proposed to improve the energy dissipation capability of the brace. In this paper, a 15-story MR-SCB braced frame is numerically analyzed to examine its seismic performance and resilience. The MR-SCB provides higher lateral stiffness than the buckling restrained brace and greater energy dissipation capability than the existing self-centering brace. The brace also exhibits a reliable recentering capacity. Under rare earthquakes, the maximum average residual deformation ratio of the structure is less than the 0.5% limit. Under mega earthquakes, the maximum average interstory drift ratio of the structure does not exceed the 2.0% elastoplastic limit, and its maximum average floor acceleration ratio is 1.57. The effects of mainshock and aftershock on the structural behavior are also investigated. The interstory drift and residual deformation of the structure increase with the increase of the intensity of the aftershock. Under aftershocks with the same intensity as the mainshocks, the maximum increment of the residual deformation ratio of the structure is 81.8%, and the average interstory drift ratios of the 12th, 7th, and 3rd stories of the structure are increased by 13.4%, 9.2% and 7.5%, respectively. The strong aftershock may significantly cause increased damage to the structure, and increase its collapse risk and residual deformation.

8.
Org Lett ; 26(11): 2297-2302, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38465891

RESUMEN

We report a deoxygenative amidation reaction of alcohols with carbamoyl chlorides to afford amides through nickel-photoredox dual catalysis. Good to excellent yields can be obtained even for diverse complex sugar and steroid derivatives. The reaction is scalable, and the synthetic utility of the reaction was demonstrated by the homologation of alcohols to deliver several important γ-amino alcohols and a synthetically challenging bioactive compound intermediate.

9.
Org Lett ; 26(32): 6921-6926, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39088260

RESUMEN

A copper-catalyzed arylation or alkenylation of quinoline N-oxides with aryl- or alkenylboronates, respectively, has been developed, which provides an efficient route for C2-substituted oxygenated quinolines under mild reaction conditions. The reaction shows a broad substrate scope for both quinoline N-oxides and aryl/alkenylboronates, mild reaction conditions, and high reaction efficiency. The formation of an aryl- or alkenyl-copper species as the key intermediate was suggested to be involved in this reaction.

10.
Org Lett ; 26(1): 264-268, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38147643

RESUMEN

A highly efficient photoinduced iron-catalyzed method has been developed for the direct use of alcohols as surrogates for organometallic reagents in the synthesis of tertiary alcohols. This method can be applied to both primary and secondary alcohols with diverse structures, enabling their reaction with aryl ketones under mild conditions. A variety of functional groups, including those that are typically reactive under conventional tertiary alcohol synthesis conditions, are compatible. Mechanistically, this reaction proceeds through the direct addition of the radical to the carbonyl pathway.

11.
Org Lett ; 26(8): 1550-1555, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38364868

RESUMEN

We report a three-component Nozaki-Hiyama-Kishi type reaction of 1,3-dioxolane, 1,3-butadienes, and aldehydes to access masked aldehyde-incorporated homoallylic alcohols, facilitated by photo-hydrogen atom transfer (HAT)/chromium dual catalysis. The diaryl ketone serves dual roles both in the HAT process and in facilitating the turnover of the chromium catalyst. A range of functional groups are tolerated owing to the mild conditions. Both aromatic and aliphatic aldehydes are suitable substrates for coupling with several 1,3-butadienes and 1,3-dioxolane.

12.
ACS Appl Mater Interfaces ; 16(32): 41960-41972, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39082953

RESUMEN

Chemotherapy is one of the main treatments for oral squamous cell carcinoma (OSCC), especially as a combined modality approach with and after surgery or radiotherapy. Limited therapeutic efficiency and serious side effects greatly restrict the clinical performance of chemotherapeutic drugs. The development of smart nanomedicines has provided new research directions, to some extent. However, the involvement of complex carrier compositions inevitably brings biosafety concerns and greatly limits the "bench-to-bed" translation of most nanomedicines reported. In this study, a carrier-free self-assembled prodrug was fabricated by two triterpenes (glycyrrhetinic acid, GA and ginsenoside Rh2, Rh2) isolated from medicinal plants, licorice, and ginseng, for the targeted and highly effective treatment of OSCC. Reactive oxygen species (ROS) self-supplied molecule TK-GA2 was synthesized with ROS-responsive thioketal linker and prodrug was prepared by a rapid-solvent-exchange method with TK-GA2 and Rh2. After administration, oral tumor cells transported large amounts of prodrugs with glucose ligands competitively. Endogenous ROS in oral tumor cells then promoted the release of GA and Rh2. GA further evoked the generation of a large number of ROS to help self-boosted drug release and increase oxidative stress, synergistically causing tumor cell apoptosis with Rh2. Overall, this carrier-free triterpene-based prodrug might provide a preeminent opinion on the design of effective chemotherapeutics with low systemic toxicity against OSCC.


Asunto(s)
Carcinoma de Células Escamosas , Liberación de Fármacos , Neoplasias de la Boca , Profármacos , Especies Reactivas de Oxígeno , Profármacos/química , Profármacos/farmacología , Profármacos/uso terapéutico , Humanos , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Especies Reactivas de Oxígeno/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Ginsenósidos/química , Ginsenósidos/farmacología , Ginsenósidos/uso terapéutico , Animales , Triterpenos/química , Triterpenos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ácido Glicirretínico/química , Ácido Glicirretínico/farmacología , Ratones , Apoptosis/efectos de los fármacos
13.
Brain Imaging Behav ; 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39388006

RESUMEN

Chronic obstructive pulmonary disease (COPD) is frequently comorbid with cognitive impairment, but it has not been paid enough attention, and its neuroanatomical characteristics have not been fully identified. Voxel-based morphometric (VBM) studies comparing gray matter (GM) abnormalities in COPD patients with healthy controls (HCs) were searched using 8 electronic databases from the inception to March 2023. Stereotactic data were extracted and tested for convergence and differences using the activation likelihood estimation (ALE) method. Moreover, based on the ALE results, a structural meta-analytic connectivity modeling (MACM) was conducted to explore the co-atrophy pattern in patients with COPD. Last, behavioral analysis was performed to assess the functional roles of the regions affected by COPD. In total, 11 studies on COPD with 949 participants were included. Voxel-based meta-analysis revealed significant GM abnormalities in the right postcentral gyrus (including inferior parietal lobule), left precentral gyrus, and left cingulate gyrus (including paracentral lobule) in patients with COPD compared with HCs. Further MACM analysis revealed a deeper co-atrophy pattern between the brain regions with abnormal GM structure and the insula in COPD patients. Behavioral analysis showed that the abnormal GM structure in the left cingulate gyrus (including paracentral lobule) was strongly associated with cognitive function, especially executive function. COPD comorbid with cognitive impairment has a specific neurostructural basis of GM structural abnormalities, which may also involve a deeper co-atrophy pattern between the insula. These findings enhance our understanding of the underlying neuropathogenesis and suggest potential imaging markers for cognitive impairment in COPD patients. PROSPERO registration number: CRD42022298722.

14.
Zhongguo Zhen Jiu ; 44(8): 966-74, 2024 Aug 12.
Artículo en Zh | MEDLINE | ID: mdl-39111798

RESUMEN

OBJECTIVE: To evaluate the reporting quality of randomized controlled trials (RCTs) of acupuncture for depression. METHODS: Systematic searches were performed in PubMed, the Cochrane Library, EMbase, CNKI, Wanfang, SinoMed and VIP Database for RCTs of acupuncture in treatment of depression. The search time was from the establishment of database to December 1, 2023, and the language restriction was Chinese and English. The reporting quality of RCTs of acupuncture for depression was evaluated using the CONSORT statement, the international standardization for trial reporting, STRICTA, the international standard for clinical trial interventions of acupuncture, and SHARE, the guideline and checklist for reporting sham acupuncture controls. RESULTS: According to the CONSORT statement items, the items with the reporting rate less than 50% was accounted for 54.05% of all of the items for Chinese articles, and there were 8 and 1 items with a reporting rate of 0% and 100%, respectively. For the English articles, the items with the reporting rate less than 50% was accounted for 35.14% of all of the items, and there were 3 and 7 items with a reporting rate of 0% and 100%, respectively. The reporting rate of 15 items in Chinese and English articles was greater than 50%, e.g. structured abstract, background and purpose. Based on STRICTA criteria, the reporting rate of either Chinese or English articles was relatively high. The items for Chinese articles with the reporting rate less than 50% was accounted for 23.53% of all of the items, and there were 1 and 4 items with a reporting rate of 0% and 100%, respectively. For English articles, the items with the reporting rate less than 50% was accounted for 11.76% of all of the items, and there was 1 item with a reporting rate of either 0% or 100%. In compliance with SHARE checklist, the reporting rate was low for either Chinese or English articles. The items with the reporting rate less than 50% was accounted for 57.89% of all of the items for Chinese articles, and there were 2 and 0 items with a reporting rate of 0% and 100%, respectively. For English articles, the items with the reporting rate less than 50% was accounted for 52.63% of all of the items, and there was 1 item with a reporting rate of 0% and 100%, respectively. CONCLUSION: The overall reporting quality of RCTs of acupuncture for depression is low currently. It is urgent to enhance the reporting of the details on sham acupuncture control especially. It is suggested that RCTs should be reported strictly in compliance with the CONSORT statement, STRICTA criteria, and SHARE checklist in the future.


Asunto(s)
Terapia por Acupuntura , Depresión , Ensayos Clínicos Controlados Aleatorios como Asunto , Terapia por Acupuntura/normas , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto/normas , Depresión/terapia , Lista de Verificación/normas , Proyectos de Investigación/normas
15.
Genes (Basel) ; 15(4)2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38674393

RESUMEN

To date, genomic and transcriptomic data on Coffea arabica L. in public databases are very limited, and there has been no comprehensive integrated investigation conducted on alternative splicing (AS). Previously, we have constructed and sequenced eighteen RNA-seq libraries of C. arabica at different ripening stages of fruit development. From this dataset, a total of 3824, 2445, 2564, 2990, and 3162 DSGs were identified in a comparison of different fruit ripening stages. The largest proportion of DSGs, approximately 65%, were of the skipped exon (SE) type. Biologically, 9 and 29 differentially expressed DSGs in the spliceosome pathway and carbon metabolism pathway, respectively, were identified. These DSGs exhibited significant variations, primarily in S1 vs. S2 and S5 vs. S6, and they involve many aspects of organ development, hormone transduction, and the synthesis of flavor components. Through the examination of research findings regarding the biological functions and biochemical pathways associated with DSGs and DEGs, it was observed that six DSGs significantly enriched in ABC transporters, namely, LOC113712394, LOC113726618, LOC113739972, LOC113725240, LOC113730214, and LOC113707447, were continually down-regulated at the fruit ripening stage. In contrast, a total of four genes, which were LOC113732777, LOC113727880, LOC113690566, and LOC113711936, including those enriched in the cysteine and methionine metabolism, were continually up-regulated. Collectively, our findings may contribute to the exploration of alternative splicing mechanisms for focused investigations of potential genes associated with the ripening of fruits in C. arabica.


Asunto(s)
Empalme Alternativo , Coffea , Frutas , Regulación de la Expresión Génica de las Plantas , Transcriptoma , Frutas/genética , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Transcriptoma/genética , Coffea/genética , Coffea/crecimiento & desarrollo , Coffea/metabolismo , Perfilación de la Expresión Génica/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
16.
Braz J Med Biol Res ; 57: e13389, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716983

RESUMEN

During the COVID-19 outbreak, there was a sharp increase in generalized anxiety disorder (GAD). Acupuncture therapy has the advantages of accurate clinical efficacy, safety and reliability, few adverse reactions, and no dependence, and is gradually becoming one of the emerging therapies for treating GAD. We present a study protocol for a randomized clinical trial with the aim of exploring the mechanism of brain plasticity in patients with GAD and evaluate the effectiveness and reliability of acupuncture treatment. Transcranial magnetic stimulation (TMS) will be used to assess cortical excitability in GAD patients and healthy people. Sixty-six GAD patients meeting the inclusion criteria will be randomly divided into two groups: TA group, (treatment with acupuncture and basic western medicine treatment) and SA group (sham acupuncture and basic western medicine treatment). Twenty healthy people will be recruited as the control group (HC). The parameters that will be evaluated are amplitude of motor evoked potentials (MEPs), cortical resting period (CSP), resting motor threshold (RMT), and Hamilton Anxiety Scale (HAMA) score. Secondary results will include blood analysis of γ-aminobutyric acid (GABA), glutamate (Glu), glutamine (Gln), serotonin (5-HT), and brain-derived nerve growth factor (BDNF). Outcomes will be assessed at baseline and after the intervention (week 8). This study protocol is the first clinical trial designed to detect differences in cerebral cortical excitability between healthy subjects and patients with GAD, and the comparison of clinical efficacy and reliability before and after acupuncture intervention is also one of the main contents of the protocol. We hope to find a suitable non-pharmacological alternative treatment for patients with GAD.


Asunto(s)
Terapia por Acupuntura , Trastornos de Ansiedad , COVID-19 , Estimulación Magnética Transcraneal , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Terapia por Acupuntura/métodos , Trastornos de Ansiedad/terapia , COVID-19/terapia , Potenciales Evocados Motores/fisiología , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados , SARS-CoV-2 , Estimulación Magnética Transcraneal/métodos , Resultado del Tratamiento
17.
Medicine (Baltimore) ; 103(16): e37848, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38640332

RESUMEN

OBJECTIVE: To investigate the clinical efficacy of fire acupuncture (FA) on plaque psoriasis (PP), exploring its suitable syndrome types, in order to achieve better therapeutic effects, accelerate the possibility of psoriasis skin lesion recovery, and provide assistance for clinical treatment. METHODS: A total of 8 patients with PP aged between 18 and 60 years were recruited and treated with FA once a week, and the lesion area and severity index (PASI), visual analog scale and pruritus were measured before, 2, 4 and 8 weeks after treatment and at the follow-up period (week 12), respectively. Visual analog scale, and dermoscopy were used for assessment. RESULTS: All patients showed improvement in pruritus after 1 FA treatment, and lesions were reduced to varying degrees after 2 weeks. Except for patients 5 and 8, who only achieved effective results due to severe disease, all other patients with psoriasis achieved significant results at 8 weeks after treatment. CONCLUSION: FA can significantly control the development of lesions, reduce the symptoms of PP lesions and pruritus, and help prevent psoriasis recurrence.


Asunto(s)
Terapia por Acupuntura , Psoriasis , Humanos , Lactante , Psoriasis/tratamiento farmacológico , Resultado del Tratamiento , Prurito/etiología , Prurito/terapia , Investigación , Índice de Severidad de la Enfermedad , Método Doble Ciego
18.
Org Lett ; 25(17): 3023-3028, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37129410

RESUMEN

Copper-catalyzed asymmetric radical cyanation reactions have emerged as a powerful strategy for rapid construction of α-chiral nitriles. However, the directly decarboxylative cyanation reactions of common alkyl carboxylic acids remain largely elusive. Herein, we report a protocol for copper-catalyzed direct and enantioselective decarboxylative cyanation of benzylic acids. The in situ activation of acid substrates by a commercially inexpensive hypervalent iodine(III) reagent promoted the yield of the alkyl radicals under mild reaction conditions without prefunctionalization. The structurally diverse chiral alkyl nitriles were produced in good yields with high enantioselectivities. In addition, the chiral products can be readily converted to other useful chiral compounds via further transformations.

19.
Org Lett ; 25(27): 5006-5010, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37384561

RESUMEN

Chiral propargylic cyanides are often used as small-molecule feedstocks for the introduction of chiral centers into various valuable products and complex molecules. Here, we have developed a highly atom-economical strategy for the chiral copper complex-catalyzed synthesis of chiral propargylic cyanides. Propargylic radicals can be smoothly obtained by direct decarboxylation of the propargylic carboxylic acids without preactivation. The reactions show excellent selectivity and functional group compatibility. Gram-scale reaction and several conversion reactions from chiral propargylic cyanide have demonstrated the synthetic value of this strategy.


Asunto(s)
Ácidos Carboxílicos , Cobre , Descarboxilación , Catálisis , Estereoisomerismo , Cianuros
20.
Adv Healthc Mater ; 12(24): e2202707, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37409443

RESUMEN

Injectable hydrogels have been extensively used in tissue engineering where high mechanical properties are key for their functionality at sites of high physiological stress. In this study, an injectable, conductive hydrogel is developed exhibiting remarkable mechanical strength that can withstand a pressure of 500 kPa (85% deformation rate) and display good fatigue resistance, electrical conductivity, and tissue adhesion. A stable covalent cross-linked network with a slip-ring structure by threading amino ß-cyclodextrin is formed onto the chain of a four-armed (polyethylene glycol) amino group, and then reacted with the four-armed (polyethylene glycol) maleimide under physiological conditions. The addition of silver nanowires enhances the hydrogel's electrical conductivity, enabling it to act as a good conductor in vivo. The hydrogel is injected into the fascial space, and the results show that the weight and muscle tone of the atrophied gastrocnemius muscle improve, subsequently alleviating muscle atrophy. Overall, this study provides a simple method for the preparation of a conductive hydrogel with high mechanical properties. In addition, the interstitial injection provides a strategy for the use of hydrogels in vivo.


Asunto(s)
Hidrogeles , Nanocables , Humanos , Hidrogeles/farmacología , Hidrogeles/química , Plata , Polietilenglicoles/farmacología , Polietilenglicoles/química , Conductividad Eléctrica , Atrofia Muscular/tratamiento farmacológico
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