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1.
Nano Lett ; 24(31): 9459-9467, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39042710

RESUMEN

Heterostructures (HSs) formed by the transition-metal dichalcogenide materials have shown great promise in next-generation (opto)electronic applications. An artificially twisted HS allows us to manipulate the optical and electronic properties. In this work, we introduce the understanding of the energy transfer (ET) process governed by the dipolar interaction in a twisted molybdenum diselenide (MoSe2) homobilayer without any charge-blocking interlayer. We fabricated an unconventional homobilayer (i.e., HS) with a large twist angle (∼57°) by combining the chemical vapor deposition (CVD) and mechanical exfoliation (Exf.) techniques to fully exploit the lattice parameter mismatch and indirect/direct (CVD/Exf.) bandgap nature. These effectively weaken the interlayer charge transfer and allow the ET to control the carrier recombination channels. Our experimental and theoretical results explain a massive HS photoluminescence enhancement due to an efficient ET process. This work shows that the electronically decoupled MoSe2 homobilayer is coupled by the ET process, mimicking a "true" heterobilayer nature.

2.
Med Res Rev ; 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39180380

RESUMEN

Chemotherapies are commonly used in cancer therapy, their applications are limited to low specificity, severe adverse reactions, and long-term medication-induced drug resistance. Poly(ADP-ribose) polymerase (PARP) inhibitors are a novel class of antitumor drugs developed to solve these intractable problems based on the mechanism of DNA damage repair, which have been widely applied in the treatment of ovarian cancer, breast cancer, and other cancers through inducing synthetic lethal effect and trapping PARP-DNA complex in BRCA gene mutated cancer cells. In recent years, PARP inhibitors have been widely used in combination with various first-line chemotherapy drugs, targeted drugs and immune checkpoint inhibitors to expand the scope of clinical application. However, the intricate mechanisms underlying the drug resistance to PARP inhibitors, including the restoration of homologous recombination, stabilization of DNA replication forks, overexpression of drug efflux protein, and epigenetic modifications pose great challenges and desirability in the development of novel PARP inhibitors. In this review, we will focus on the mechanism, structure-activity relationship, and multidrug resistance associated with the representative PARP inhibitors. Furthermore, we aim to provide insights into the development prospects and emerging trends to offer guidance for the clinical application and inspiration for the development of novel PARP inhibitors and degraders.

3.
J Org Chem ; 89(4): 2190-2199, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38279922

RESUMEN

Ketenimines represent an important class of reactive species, useful synthetic intermediates, and synthons. However, in general, ketenimines preferentially undergoes nucleophilic addition reactions with hydroxyl and amino groups, and carbon functional groups remain a less studied subset of such systems. Herein, we develop a straightforward syntheses of pyridin-4(1H)-imines that is achieved by cyclization of a reacting enaminone unit with α-acylketenimine which is generated from the reactions of sulfonyl azides and terminal ynones in situ (CuAAC/Ring cleavage reaction). The cascade process preferentially starts with the nucleophilic α-C of the enaminone unit instead of an amino group, attacking the electron-deficient central carbon of ketenimine, and the chemoselectivity unconventional products pyridin-4(1H)-imines were formed by intramolecular cyclization.

4.
J Org Chem ; 89(12): 9139-9143, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38861494

RESUMEN

Conjugated ynones represent an important class of reactive species, useful synthetic intermediates, and synthons. However, the reactivity and synthetic applications of ynones are usually focused on the transformation of mono- or dual-functional groups. Herein, we developed a straightforward synthesis of pyridin-2(1H)-imines from the transformation of conjugated ynones. This cascade process probably began with a Michael addition of ynones and 2-aminopyridines, further underwent an intramolecular cyclization to generate the N,O-bidentate intermediates, and finally reacted with sulfonyl azides giving the pyridin-2(1H)-imines with accompanying loss of diazo.

5.
J Nat Prod ; 87(9): 2310-2316, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39162422

RESUMEN

The revised structure, 2, assigned to the title natural product has been prepared by chemical synthesis using a reaction sequence involving six simple steps starting from 2,3-dimethoxybenzaldehyde and proceeding via intermediates 8, 12, and 14. A comparison of the NMR data acquired on synthetically derived compound 2 with those reported for the natural product reveals an excellent match. Preliminary biological screening of compound 2 along with analogues/precursors 7, 9, 10, 11, 13, 14, and 15 revealed that none exhibited antibacterial, antifungal or cytotoxic effects.


Asunto(s)
Alcaloides , Estructura Molecular , Alcaloides/química , Alcaloides/farmacología , Alcaloides/síntesis química , Microbiología del Suelo , Hypocreales/química , Resonancia Magnética Nuclear Biomolecular , Pruebas de Sensibilidad Microbiana , Benzaldehídos/química , Benzaldehídos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química
6.
Sensors (Basel) ; 24(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38339440

RESUMEN

The spectrum confocal displacement sensor is an innovative type of photoelectric sensor. The non-contact advantages of this method include the capacity to obtain highly accurate measurements without inflicting any harm as well as the ability to determine the object's surface contour recovery by reconstructing the measurement data. Consequently, it has been widely used in the field of three-dimensional topographic measuring. The spectral confocal displacement sensor consists of a light source, a dispersive objective, and an imaging spectrometer. The scanning mode can be categorized into point scanning and line scanning. Point scanning is inherently present when the scanning efficiency is low, resulting in a slower measurement speed. Further improvements are necessary in the research on the line-scanning type. It is crucial to expand the measurement range of existing studies to overcome the limitations encountered during the detection process. The objective of this study is to overcome the constraints of the existing line-swept spectral confocal displacement sensor's limited measuring range and lack of theoretical foundation for the entire system. This is accomplished by suggesting an appropriate approach for creating the optical design of the dispersive objective lens in the line-swept spectral confocal displacement sensor. Additionally, prism-grating beam splitting is employed to simulate and analyze the imaging spectrometer's back end. The combination of a prism and a grating eliminates the spectral line bending that occurs in the imaging spectrometer. The results indicate that a complete optical pathway for the line-scanning spectral confocal displacement sensor has been built, achieving an axial resolution of 0.8 µm, a scanning line length of 24 mm, and a dispersion range of 3.9 mm. This sensor significantly expands the range of measurements and fills a previously unaddressed gap in the field of analyzing the current stage of line-scanning spectral confocal displacement sensors. This is a groundbreaking achievement for both the sensor itself and the field it operates in. The line-scanning spectral confocal displacement sensor's design addresses a previously unmet need in systematic analysis by successfully obtaining a wide measuring range. This provides systematic theoretical backing for the advancement of the sensor, which has potential applications in the industrial detection of various ranges and complicated objects.

7.
Nano Lett ; 23(18): 8593-8601, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37625135

RESUMEN

Despite the great progress of current bacterially based biotherapeutics, their unsatisfying efficacy and underlying safety problems have limited their clinical application. Herein, inspired by probiotic Escherichia coli strain Nissle 1917, probiotic-derived outer membrane vesicles (OMVs) are found to serve as an effective therapeutic platform for the treatment of inflammatory bowel disease (IBD). To further enhance the therapeutic effect, the probiotic-derived OMV-encapsulating manganese dioxide nanozymes are constructed, named nanoprobiotics, which can adhere to inflamed colonic epithelium and eliminate intestinal excess reactive oxygen species in the murine IBD model. Moreover, combined with the anti-inflammatory medicine metformin, nanoprobiotics could further remold the pro-inflammatory microenvironment, improve the overall richness and diversity of the gut microbiota, and exhibit better therapeutic efficacy than commercial IBD chemotherapeutics. Importantly, insignificant overt systemic toxicity in this treatment was observed. By integrating cytokine storm calm with biotherapy, we develop a safe and effective bionanoplatform for the effective treatment of inflammation-mediated intestinal diseases.

8.
Chemistry ; 29(5): e202203265, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36278311

RESUMEN

Among the parent borirane, benzoborirene and ortho-dicarbadodecaborane-fused borirane, the latter possesses the highest ring strain and the highest Lewis acidity according to our density functional theory (DFT) studies. The synthesis of this class of compounds is thus considerably challenging. The existing examples require either a strong π-donating group or an extra ligand for B-coordination, which nevertheless suppresses or completely turns off the Lewis acidity. The title compound, which possesses both features, not only allows the 1,2-insertion of P=O, C=O or C≡N to proceed under milder conditions, but also enables the heretofore unknown dearomative 1,4-insertion of Ar-(C=O)- into a B-C bond. The fusion of strained molecular systems to an o-carborane cage shows great promise for boosting both the ring strain and acidity.


Asunto(s)
Boranos , Ácidos de Lewis , Ácidos de Lewis/química , Teoría Funcional de la Densidad , Boranos/química
9.
Theor Appl Genet ; 136(7): 163, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37368122

RESUMEN

KEY MESSAGE: We demonstrated a short-cycle B. napus line, Sef1, with a highly efficient and fast transformation system, which has great potential in large-scale functional gene analysis in a controlled environment. Rapeseed (Brassica napus L.) is an essential oil crop that accounts for a considerable share of global vegetable oil production. Nonetheless, studies on functional genes of B. napus are lagging behind due to the complicated genome and long growth cycle, this is largely due to the limited availability of gene analysis and modern genome editing-based molecular breeding. In this study, we demonstrated a short-cycle semi-winter-type Brassica napus 'Sef1' with very early-flowering and dwarf phenotype, which has great potential in large-scale indoor planting. Through the construction of an F2 population of Sef1 and Zhongshuang11, bulked segregant analysis (BSA) combined with the rape Bnapus50K SNP chip assay method was used to identify the early-flowering genes in Sef1, and a mutation in BnaFT.A02 was identified as a major locus significantly affecting the flowering time in Sef1. To further investigate the mechanism of early flowering in Sef1 and discover its potential in gene function analysis, an efficient Agrobacterium-mediated transformation system was established. The average transformation efficiency with explants of hypocotyls and cotyledons was 20.37% and 12.8%, respectively, and the entire transformation process took approximately 3 months from explant preparation to seed harvest of transformed plants. This study demonstrates the great potential of Sef1 for large-scale functional gene analysis.


Asunto(s)
Brassica napus , Brassica napus/genética , Genómica , Fenotipo , Análisis de Secuencia por Matrices de Oligonucleótidos , Ambiente Controlado
10.
Molecules ; 28(15)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37570705

RESUMEN

An oxidant-free and highly efficient synthesis of phenolic quinazolin-4(3H)-ones was achieved by simply stirring a mixture of 2-aminobenzamides, sulfonyl azides, and terminal alkynes. The intermediate N-sulfonylketenimine underwent two nucleophilic additions and the sulfonyl group eliminated through the power of aromatization. The natural product 2-(4-hydroxybenzyl)quinazolin-4(3H)-one can be synthesized on a large scale under mild conditions with this method.

11.
Molecules ; 28(18)2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37764287

RESUMEN

While fluorescent organic materials have many potential as well as proven applications and so have attracted significant attention, pyridine-olefin conjugates remain a less studied subset of such systems. Herein, therefore, we report on the development of the straightforward syntheses of pyridin-1(2H)-ylacrylates and the outcomes of a study of the effects of substituents on their fluorescent properties. Such compounds were prepared using a simple, metal-free and three-component coupling reaction involving 2-aminopyridines, sulfonyl azides and propiolates. The fluorescent properties of the ensuing products are significantly affected by the positions of substituents on the cyclic framework, with those located in central positions having the greatest impact. Electron-withdrawing groups tend to induce blue shifts while electron-donating ones cause red shifts. This work highlights the capacity that the micro-modification of fluorescent materials provides for fine-tuning their properties such that they may be usefully applied to, for example, the study of luminescent materials.

12.
Plant Mol Biol ; 108(1-2): 1-14, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34846608

RESUMEN

KEY MESSAGE: Developing embryo and endosperm of sorghum show substantial and multifaceted differences in gene expression and alternative splicing, which are potentially relevant to heterosis. Differential regulation of gene expression and alternative splicing (AS) are major molecular mechanisms dictating plant growth and development, as well as underpinning heterosis in F1 hybrids. Here, using deep RNA-sequencing we analyzed differences in genome-wide gene expression and AS between developing embryo and endosperm, and between F1 hybrids and their pure-line parents in sorghum. We uncover dramatic differences in both gene expression and AS between embryo and endosperm with respect to gene features and functions, which are consistent with the fundamentally different biological roles of the two tissues. Accordingly, F1 hybrids showed substantial and multifaceted differences in gene expression and AS compared with their pure-line parents, again with clear tissue specificities including extents of difference, genes involved and functional enrichments. Our results provide useful transcriptome resources as well as novel insights for further elucidation of seed yield heterosis in sorghum and related crops.


Asunto(s)
Empalme Alternativo/genética , Endospermo/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/genética , Semillas/crecimiento & desarrollo , Sorghum/genética , Endospermo/genética , Expresión Génica/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Hibridación Genética/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Semillas/genética , Sorghum/crecimiento & desarrollo , Sorghum/metabolismo , Especificidad de la Especie
13.
J Cardiovasc Magn Reson ; 24(1): 59, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36372884

RESUMEN

BACKGROUND: Four-dimensional flow cardiovascular magnetic resonance imaging (4D flow CMR) allows comprehensive assessment of pulmonary artery (PA) flow dynamics. Few studies have characterized longitudinal changes in pulmonary flow dynamics and right ventricular (RV) recovery following a pulmonary endarterectomy (PEA) for patients with chronic thromboembolic pulmonary hypertension (CTEPH). This can provide novel insights of RV and PA dynamics during recovery. We investigated the longitudinal trajectory of 4D flow metrics following a PEA including velocity, vorticity, helicity, and PA vessel wall stiffness. METHODS: Twenty patients with CTEPH underwent pre-PEA and > 6 months post-PEA CMR imaging including 4D flow CMR; right heart catheter measurements were performed in 18 of these patients. We developed a semi-automated pipeline to extract integrated 4D flow-derived main, left, and right PA (MPA, LPA, RPA) volumes, velocity flow profiles, and secondary flow profiles. We focused on secondary flow metrics of vorticity, volume fraction of positive helicity (clockwise rotation), and the helical flow index (HFI) that measures helicity intensity. RESULTS: Mean PA pressures (mPAP), total pulmonary resistance (TPR), and normalized RV end-systolic volume (RVESV) decreased significantly post-PEA (P < 0.002). 4D flow-derived PA volumes decreased (P < 0.001) and stiffness, velocity, and vorticity increased (P < 0.01) post-PEA. Longitudinal improvements from pre- to post-PEA in mPAP were associated with longitudinal decreases in MPA area (r = 0.68, P = 0.002). Longitudinal improvements in TPR were associated with longitudinal increases in the maximum RPA HFI (r=-0.85, P < 0.001). Longitudinal improvements in RVESV were associated with longitudinal decreases in MPA fraction of positive helicity (r = 0.75, P = 0.003) and minimum MPA HFI (r=-0.72, P = 0.005). CONCLUSION: We developed a semi-automated pipeline for analyzing 4D flow metrics of vessel stiffness and flow profiles. PEA was associated with changes in 4D flow metrics of PA flow profiles and vessel stiffness. Longitudinal analysis revealed that PA helicity was associated with pulmonary remodeling and RV reverse remodeling following a PEA.


Asunto(s)
Hipertensión Pulmonar , Embolia Pulmonar , Humanos , Hipertensión Pulmonar/diagnóstico por imagen , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/cirugía , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/cirugía , Valor Predictivo de las Pruebas , Endarterectomía/métodos , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/cirugía , Imagen por Resonancia Magnética , Remodelación Ventricular , Espectroscopía de Resonancia Magnética , Función Ventricular Derecha
14.
Cardiol Young ; 32(7): 1122-1128, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34558399

RESUMEN

INTRODUCTION: Cardiopulmonary resuscitation (CPR) in the shunted single-ventricle population is associated with poor outcomes. Interposed abdominal compression-cardiopulmonary resuscitation, or IAC-CPR, is an adjunct to standard CPR in which pressure is applied to the abdomen during the recoil phase of chest compressions. METHODS: A lumped parameter model that represents heart chambers and blood vessels as resistors and capacitors was used to simulate blood flow in both Blalock-Taussig-Thomas and Sano circulations. For standard CPR, a prescribed external pressure waveform was applied to the heart chambers and great vessels to simulate chest compressions. IAC-CPR was modelled by adding phasic compression pressure to the abdominal aorta. Differential equations for the model were solved by a Runge-Kutta method. RESULTS: In the Blalock-Taussig-Thomas model, mean pulmonary blood flow during IAC-CPR was 30% higher than during standard CPR; cardiac output increased 21%, diastolic blood pressure 16%, systolic blood pressure 8%, coronary perfusion pressure 17%, and coronary blood flow 17%. In the Sano model, pulmonary blood flow during IAC-CPR increased 150%, whereas cardiac output was improved by 13%, diastolic blood pressure 18%, systolic blood pressure 8%, coronary perfusion pressure 15%, and coronary blood flow 14%. CONCLUSIONS: In this model, IAC-CPR confers significant advantage over standard CPR with respect to pulmonary blood flow, cardiac output, blood pressure, coronary perfusion pressure, and coronary blood flow. These results support the notion that single-ventricle paediatric patients may benefit from adjunctive resuscitation techniques, and underscores the need for an in-vivo trial of IAC-CPR in children.


Asunto(s)
Reanimación Cardiopulmonar , Abdomen , Reanimación Cardiopulmonar/métodos , Niño , Hemodinámica , Humanos , Modelos Teóricos , Presión
15.
J Org Chem ; 86(13): 9155-9162, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-34137260

RESUMEN

An operationally simple synthesis of Z-configured and C3-unsubstituted N-sulfonyl-2-iminocoumarins (e.g., 8a) that proceeds under mild conditions is achieved by reacting 2-(1-hydroxyprop-2-yn-1-yl)phenols (e.g., 6a) with sulfonyl azides (e.g., 7a). The cascade process involved likely starts with a copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction. This is followed by ring-opening of the resulting metalated triazole (with accompanying loss of nitrogen), reaction of the ensuing ketenimine with the pendant phenolic hydroxyl group, and finally dehydration of the (Z)-N-(4-hydroxychroman-2-ylidene)sulfonamide so formed.


Asunto(s)
Azidas , Cobre , Alquinos , Catálisis , Reacción de Cicloadición , Fenoles
16.
Org Biomol Chem ; 19(17): 3868-3872, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33949559

RESUMEN

A library of medicinally and synthetically important nicotinimidamides was synthesized by a copper-catalyzed multicomponent domino reaction of oxime esters, terminal ynones, sulfonyl azides, aryl aldehydes and acetic ammonium. Its synthetic pathway involves the formation of a highly reactive N-sulfonyl acetylketenimine, characterized by high selectivity, combinations of potential nucleophiles and electrophiles, mild reaction conditions and a wide substrate scope, and is a rare five-component example of a CuAAC/ring-opening reaction.

17.
Ophthalmic Res ; 2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-33530086

RESUMEN

BACKGROUND: MicroRNAs (miRNAs) play an important role in the proliferation and migration of retinal endothelial cells in patients with hypertension and hypertensive retinopathy (HR). This study aimed to investigate the clinical value of miR-637 in HR and its role in retinal endothelial cell proliferation and migration. METHODS: A total of 126 subjects were recruited for the study, including 42 patients with hypertension (male/female 25/17), 42 healthy individuals (male/female 20/22), and 42 cases with HR (male/female 20/22). Except SBP and DBP, there was no significant difference in other indexes among the three groups. qRT-PCR was used to detect the expression of miR-637. The receiver operating curve (ROC) was used for diagnosis value analysis. Logistic regression analysis was used to evaluate the relationship between miR-637 and HR. CCK-8 and Transwell were used to detect the effect of miR-637 on the proliferation and migration of HUVECs. RESULTS: Compared with hypertensive patients, HR patients had the lowest expression of miR-637. The area under the curve (AUC) of miR-637 detected by the ROC curve method is 0.892, which has the ability to distinguish hypertension and HR patients. Logistic regression analysis showed that miR-637 was an independent influence factor in HR. Cell experiment results showed that overexpression of miR-637 significantly inhibited cell proliferation and migration, while downregulation of miR-637 had the opposite effect. Luciferase analysis showed that STAT3 was the target gene of miR-637. CONCLUSION: Our data indicate that miR-637 is a potential non-invasive marker for patients with HR. The action of miR-637 on STAT3 may inhibit the proliferation and migration of retinal endothelial cells, providing a possible target for the treatment of HR.

18.
Molecules ; 26(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204392

RESUMEN

N-Sulfonyl amidines are developed from a Cu-catalyzed three-component reaction from sulfonyl hydrazines, terminal alkynes and sulfonyl azides in toluene at room temperature. Particularly, the intermediate N-sulfonylketenimines was generated via a CuAAC/ring-opening procedure and took a nucleophilic addition with the weak nucleophile sulfonyl hydrazines. In addition, the stability of the product was tested by a HNMR spectrometer.

19.
Molecules ; 27(1)2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-35011453

RESUMEN

Development of novel anticancer therapeutic candidates is one of the key challenges in medicinal chemistry. Podophyllotoxin and its derivatives, as a potent cytotoxic agent, have been at the center of extensive chemical amendment and pharmacological investigation. Herein, a new series of podophyllotoxin-N-sulfonyl amidine hybrids (4a-4v, 5a-5f) were synthesized by a CuAAC/ring-opening procedure. All the synthesized podophyllotoxins derivatives were evaluated for in vitro cytotoxic activity against a panel of human lung (A-549) cancer cell lines. Different substituents', or functional groups' antiproliferative activities were discussed. The -CF3 group performed best (IC50: 1.65 µM) and exhibited more potent activity than etoposide. Furthermore, molecular docking and dynamics studies were also conducted for active compounds and the results were in good agreement with the observed IC50 values.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Diseño de Fármacos , Podofilotoxina/química , Podofilotoxina/farmacología , Antineoplásicos/síntesis química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Técnicas de Química Sintética , Humanos , Conformación Molecular , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Podofilotoxina/síntesis química , Relación Estructura-Actividad
20.
J Am Chem Soc ; 142(41): 17243-17249, 2020 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-32941023

RESUMEN

The base-free benzoborirene 1,2-BR-1,2-C6H4 (7) and its three-dimensional inorganic analogue 1,2-BR-1,2-C2B10H10 (13) have been successfully synthesized by Cp2ZrBr2 and LiCl elimination, respectively. The Cl analogue of the key intermediate for the formation of benzoborirene 7 has been isolated and structurally characterized, thus suggesting the reaction pathway via benzyne Zr complex formation, B-Br/Cbenzyne-Zr σ-bond metathesis, and a Cp2ZrBr2 elimination/ring-closing process. The rationality of the reaction pathway has been confirmed by DFT calculations. In addition, the title compounds shared the same reactivity pattern (i.e., 1,3-silyl migration) toward MeIiPr (8), thus allowing for the synthetic approach to the first carborane-substituted iminoborane 14.

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