Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Clin Cosmet Investig Dermatol ; 17: 637-647, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505806

RESUMO

Aim: Mycobacterium abscessus is ubiquitous in the environment and seldom causes infections in immunocompetent individuals. However, skin and soft tissue infections caused by M. abscessus have been reported in recent years. Additionally, the cutaneous infections or outbreaks post cosmetic surgery caused by M. abscessus have been increasing due to the popularity of plastic surgery. The main modes of transmission are through contaminated saline, disinfectants, or surgery equipment, as well as close contact between patients. This article describes three patients who were admitted to our hospital between November 2019 and October 2020. They presented with long-term non-healing wounds caused by M. abscessus infection after undergoing plastic surgery. Symptoms presented by the three patients included swelling, ulceration, secretion, and pain. After identification of M. abscessus with Ziehl-Neelsen staining and MALDI-TOF MS system, the patients were treated with surgical debridement and clarithromycin. Conclusion: It is important to note that a long-term wound that does not heal, especially after plastic surgery, should raise suspicion for M. abscessus infection. The infection mechanism in these three patients may have been due to exposure to surgical equipment that was not properly sterilized or due to poor sterile technique by the plastic surgeon. To prevent such infections, it is important to ensure proper sterilization of surgical equipment and saline.

2.
Nat Commun ; 15(1): 1672, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395923

RESUMO

The practical applications of solar-driven water splitting pivot on significant advances that enable scalable production of robust photoactive films. Here, we propose a proof-of-concept for fabricating robust photoactive films by a particle-implanting technique (PiP) which embeds semiconductor photoabsorbers in the liquid metal. The strong semiconductor/metal interaction enables resulting films efficient collection of photogenerated charges and superior photoactivity. A photoanode of liquid-metal embraced BiVO4 can stably operate over 120 h and retain ~ 70% of activity when scaled from 1 to 64 cm2. Furthermore, a Z-scheme photocatalyst film of liquid-metal embraced BiVO4 and Rh-doped SrTiO3 particles can drive overall water splitting under visible light, delivering an activity 2.9 times higher than that of the control film with gold support and a 110 h stability. These results demonstrate the advantages of the PiP technique in constructing robust and efficient photoactive films for artificial photosynthesis.

3.
Molecules ; 29(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338353

RESUMO

The interaction of fullerenes and their derivatives with environmental molecules such as oxygen or water was crucial for the rational design of low-dimensional materials and devices. In this paper, the near-edge X-ray absorption fine structure (NEXAFS), X-ray emission spectroscopy (XES) and X-ray photoelectron spectroscopy (XPS) shake-up satellites were employed to distinguish the oxides and hydrates of the fullerene C60 and azafullerene C59N families. The study includes various isomers, such as the open [5,6] and closed [6,6] isomers of C60O, C60H(OH), C60-O-C60, C60H-O-C60H, C59N(OH) and C59N-O-C59N, based on density functional theory. These soft X-ray spectra offered comprehensive insights into the molecular orbitals of these azafullerene molecular groups. The oxygen K-edge NEXAFS, carbon and oxygen K-edge XPS shake-up satellite spectra provided valuable tools for distinguishing oxides or hydrates of fullerene C60 and azafullerene C59N. Our findings could significantly benefit the development of fullerene functional molecular materials and expand the application scope of soft X-ray spectroscopy as a molecular fingerprinting tool for the fullerene family.

4.
Cell Biochem Biophys ; 80(1): 139-150, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34297270

RESUMO

This study investigated the potential genes and related pathways in burn-induced myocardial injury. Rat myocardial injury induced by third-degree burn and the histopathological structures, apoptosis, and cardiac injury markers were then identified using hematoxylin & eosin staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining, and enzyme-linked immunosorbent assay. Next, differentially expressed mRNAs were screened through next-generation sequencing (NGS), followed by functional annotation and key gene validation through quantitative reverse transcription-polymerase chain reaction. Subsequently, CD14 was screened out, and small interfering RNAs against CD14 were transfected to H9C2 cells to further verify the role of CD14 in burn-induced injury. The results showed that third-degree burn could markedly damage the structure of myocardial tissue, induce the apoptosis of myocardial cells, and increase the levels of myocardial injury-related markers, suggesting that burns could induce myocardial injury in rats. Besides, NGS data discovered that third-degree burn could result in 416 differentially upregulated mRNAs and 285 differentially downregulated mRNAs in myocardial tissue. It was also disclosed that differentially expressed mRNAs were mainly enriched in the phosphatidylinositol 3-kinase/Akt, mitogen-activated protein kinase (MAPK), and tumor necrosis factor signaling pathways. Furthermore, cell viability was significantly decreased in H9C2 cells treated with 10% rat burn serum. CD14 was significantly differentially expressed and screened out for further studies. Treatment with burn serum can significantly upregulate the phosphorylation level of extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinase and the expression of cleaved caspase-3 and downregulate the expression of Bcl2 when compared with those in negative control of small interfering RNA transfected H9C2 cells, whereas interfering with CD14 expression reversed the effects of burn serum. The study demonstrated that burn serum treatment could activate the MAPK signaling pathway to promote cell apoptosis, and it can be reversed by interfering with the expression of CD14.


Assuntos
Queimaduras , Proteínas Quinases Ativadas por Mitógeno , Animais , Apoptose/genética , Queimaduras/complicações , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Transdução de Sinais/genética
5.
Int J Immunopathol Pharmacol ; 35: 20587384211016724, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34011185

RESUMO

Activated M2 macrophages are involved in hypertrophic scar (HS) formation via manipulating the differentiation of fibroblasts to myofibroblasts having the proliferative capacity and biological function. However, the function of exosomes derived from M2 macrophages in HS formation is unclear. Thus, this study aims to investigate the role of exosomes derived by M2 in the formation of HS. To understand the effect of exosomes derived from M2 macrophages on formation of HS, M2 macrophages were co-cultured with human dermal fibroblast (HDF) cells. Cell Counting Kit-8 assay was performed to evaluate HDF proliferation. To evaluate the migration and invasion of HDFs, wound-healing and transwell invasion assays were performed, respectively. To investigate the interaction between LINC01605 and miR-493-3p, a dual-luciferase reporter gene assay was adopted; consequently, an interaction between miR-493-3p and AKT1 was detected. Our results demonstrated that exosomes derived from M2 macrophages promoted the proliferation, migration, and invasion of HDFs. Additionally, we found that long noncoding RNA LINC01605, enriched in exosomes derived from M2 macrophages, promoted fibrosis of HDFs and that GW4869, an inhibitor of exosomes, could revert this effect. Mechanistically, LINC01605 promoted fibrosis of HDFs by directly inhibiting the secretion of miR-493-3p, and miR-493-3p down-regulated the expression of AKT1. Exosomes derived from M2 macrophages promote the proliferation and migration of HDFs by transmitting LINC01605, which may activate the AKT signaling pathway by sponging miR-493-3p. Our results provide a novel approach and basis for further investigation of the function of M2 macrophages in HS formation.


Assuntos
Exossomos , Fibroblastos/patologia , Macrófagos/imunologia , MicroRNAs/imunologia , RNA Longo não Codificante/imunologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Fibroblastos/imunologia , Humanos
6.
Respir Res ; 22(1): 145, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33975616

RESUMO

BACKGROUND: This study was designed to investigate the difference between brain metastases (BM) and non-brain metastases (non-BM) treated by osimertinib in advanced patients with an acquired EGFR T790M mutation after obtaining first-generation EGFR-TKI resistance. METHODS: A total number of 135 first-generation EGFR-TKI-resistant patients with an acquired EGFR T790M mutation were retrospectively analyzed. The patients were divided into BM and non-BM groups. According to the type of treatment (whether brain radiotherapy), the BM patients were divided into an osimertinib combined with brain radiotherapy group and an osimertinib without brain radiotherapy group. In addition, according to the type of BM (the sequence between BM and osimertinib), the BM patients were subdivided into an osimertinib after BM group (initial BM developed after obtaining first-generation EGFR-TKI resistance) and an osimertinib before BM group (first-generation EGFR-TKI resistance then osimertinib administration performed; initial BM was not developed until osimertinib resistance). The progression-free survival (PFS) and overall survival (OS) were evaluated. The primary endpoint was OS between BM and no-BM patients. The secondary endpoints were PFS of osimertinib, and OS between brain radiotherapy and non-brain radiotherapy patients. RESULTS: A total of 135 patients were eligible and the median follow-up time of all patients was 50 months. The patients with BM (n = 54) had inferior OS than those without BM (n = 81) (45 months vs. 55 months, P = 0.004). And in BM group, the OS was longer in patients that received osimertinib combined with brain radiotherapy than in those without brain radiotherapy (53 months vs. 40 months, P = 0.014). In addition, the PFS was analysed according to whether developed BM after osimertinib resistance. The PFS of the patients that developed BM after acquiring osimertinib resistance was shorter than that without BM development, whether patients developed initial BM after first-generation EGFR-TKI resistance (7 months vs. 13 months, P = 0.003), or developed non-BM after first-generation EGFR-TKI resistance (13 months vs. 17 months, P < 0.001). CONCLUSIONS: In advanced patients with an acquired EGFR T790M mutation after obtaining first-generation EGFR-TKI resistance, osimertinib may be more limited in its control in BM than in non-BM. Also, osimertinib combined with brain radiotherapy may improve the survival time of BM patients.


Assuntos
Acrilamidas/uso terapêutico , Adenocarcinoma de Pulmão/tratamento farmacológico , Compostos de Anilina/uso terapêutico , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/antagonistas & inibidores , Neoplasias Encefálicas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Acrilamidas/efeitos adversos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/secundário , Compostos de Anilina/efeitos adversos , Antineoplásicos/efeitos adversos , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/secundário , Quimiorradioterapia , Irradiação Craniana , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo
7.
Biosci Biotechnol Biochem ; 84(12): 2521-2528, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32867589

RESUMO

Fifteen percent third-degree burn rat model was used to identify miRNAs that are markers of burn injury-induced myocardial damage. Cardiac tissues were evaluated to determine miRNA profile sequencing. Pearson's correlation analysis was used between miRNAs and injury markers. ROC curve analysis was used to estimate miRNA's sensitivity and specificity for the diagnosis of myocardial damage caused by burn injury. The sequencing analysis revealed 23 differentially expressed miRNAs. Pearson's correlation analysis revealed that rno-miR-190b-3p and C5b9, rno-miR-341, rno-miR-344b-3p and TnI, rno-miR-344b-3p and CK-MB were significantly positively correlated, respectively. ROC curve analysis demonstrated that rno-miR-341, rno-miR-344b-3p, and rno-miR-190b-3p exhibited high sensitivity and specificity for the diagnosis of myocardial damage caused by burn injury. In conclusion, our results suggest that rno-miR-341, rno-miR-344b-3p, and rno-miR-190b-3p have the potential to be used as sensitive and specific biomarkers to diagnose myocardial damage caused by burn injury.


Assuntos
Queimaduras/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Miocárdio/metabolismo , Animais , Queimaduras/patologia , Ontologia Genética , Genômica , Masculino , Ratos
8.
J Phys Chem Lett ; 11(15): 6320-6329, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32660249

RESUMO

Achieving an effective nitrogen reduction reaction (NRR) under mild conditions is a great challenge for industrial ammonia synthesis. NRR is often accompanied by a competing hydrogen evolution reaction (HER), which causes an extremely low Faraday efficiency. We systematically investigated the NRR reactivity of atom-pair catalysts (APCs) formed by 20 transition metal (TM) elements supported by N-doped graphene via three reaction pathways. By analyzing the correlation among the limiting potential, Gibbs free energy, and d-band center, we evaluated the activity trends of the TM APCs. Our computations revealed that the enzymatic pathway is the most suitable reaction pathway for the TM APCs, and the intrinsic activity trend of these APCs can be determined by the d-band center-based descriptor, which has a simple linear correlation with the bonding/antibonding orbital population. In addition, the NRR APCs with excellent performance have been screened out through selective analysis of the competing HER in the electrocatalytic NRR process.

9.
Dalton Trans ; 49(21): 7189-7196, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32415829

RESUMO

1,2-Insertion reactions of alkynes into the Ge-C bonds in dibromodigermenes afford stable crystalline bromovinylgermylenes. In contrast to previously reported Lewis-base-supported vinylgermylenes, the bromovinylgermylene obtained from reaction of the bromogermylene with 3-hexyne via such an 1,2-insertion is a donor-free monomer. A feasible reaction mechanism, proposed on the basis of the observed experimental results in combination with theoretical calculations, suggests that the [1+2]-cycloadduct and the insertion product are the kinetic and thermodynamic product, respectively.

10.
J Am Chem Soc ; 141(6): 2263-2267, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30704238

RESUMO

The first examples of stable, crystalline, and air-sensitive 1,4-digermabenzenes were isolated. These species photochemically isomerize into the corresponding air-stable digerma-Dewar-benzenes. More importantly, alkyl-substituted Dewar-type-1,4-digermabenzenes can be considered as reversible "air-stable activators" for small molecules such as dihydrogen, carbon dioxide, and acetylene at room temperature. The regeneration of these activators can be accomplished via a thermal retro-isomerization that affords the corresponding 1,4-digermabenzenes.

11.
Chem Commun (Camb) ; 55(3): 405-407, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30542688

RESUMO

The diarylstannylenes, Sn(AriPr4)2 and Sn(AriPr6)2, (AriPr4 = C6H3-2,6-(C6H3-2,6-iPr2)2, AriPr6 = C6H3-2,6-(C6H2-2,4,6-iPr3)2), undergo a facile migratory insertion reaction with ethylene at 60 °C to afford the alkyl aryl stannylenes AriPr4SnCH2CH2AriPr4 and AriPr6SnCH2CH2AriPr6 which were characterized via1H, 13C and 119Sn NMR, UV-vis and IR spectroscopy, as well as by X-ray crystallography. Quantum mechanical calculations were performed, and two potential mechanisms were identified, with a migratory insertion reaction pathyway being energetically preferred.

12.
Chem Pharm Bull (Tokyo) ; 66(12): 1203-1206, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30504635

RESUMO

Axially chiral binaphthothiophene dicarboxylic acid was prepared as a novel functionalized chiral dicarboxylic acid. The crystal structures of both the racemic form and its salt with chiral diamine revealed the intramolecular S···O interactions (chalcogen bonds) between the sulfur in the naphthothiophene rings and the oxygen of the carboxy groups. The negative-positive and the positive-negative Cotton effects from longer to shorter wavelengths were observed for (R)- and (S)-enantiomers, respectively, in the circular dichroism (CD) spectra.


Assuntos
Ácidos Dicarboxílicos/química , Tiofenos/química , Ácidos Dicarboxílicos/síntese química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo , Tiofenos/síntese química
13.
Chem Asian J ; 13(24): 3800-3817, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30320958

RESUMO

Dimetallynes (RE≡ER; E=Si, Ge, Sn, Pb), i.e., systems that contain triple bonds between heavier group-14 elements represent the heavier homologues of alkynes. The high reactivity of disilynes, digermynes, distannynes, and diplumbynes can be interpreted in terms of their unique bonding situation, which includes a trans-bent structure, a small HOMO-LUMO gap, a partial diradical character, their electronic nature, and interactions between bulky substituents. Relatively recent developments in the area of sterically demanding substituents have permitted isolating some stable compounds with a triple bond between heavier group-14 elements. The structural features of these triple-bonded compounds and their reactivity toward small molecules have been investigated using experimental and theoretical approaches. This review focuses on recent developments regarding the reactivity of stable compounds with a triple bond between heavier group-14 elements toward small molecules, where the results were examined using quantum chemical methods. A comprehensive review on carbon chemistry is beyond the scope of this focus review.

14.
Dalton Trans ; 47(38): 13318-13322, 2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30160268

RESUMO

A stable 3,5-diphenyl-1,2-disilabenzene was selectively synthesized by the reaction between the isolable disilyne TbbSi[triple bond, length as m-dash]SiTbb (Tbb = 2,6-[CH(SiMe3)2]2-4-t-Bu-phenyl) with phenylacetylenes. Its molecular structure and physical properties were examined and compared to those of the 1,2-disilabenzene that was obtained from the reaction between TbbSi[triple bond, length as m-dash]SiTbb and acetylene. Moreover, a plausible formation mechanism for this reaction is discussed.

15.
Angew Chem Int Ed Engl ; 57(17): 4663-4667, 2018 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-29451348

RESUMO

Metal-free dehydrogenative couplings of aryliodanes with phenols to afford 2-hydroxy-2'-iodobiaryls have been developed. This reaction proceeds through ligand exchange on the hypervalent iodine atom followed by a [3,3] sigmatropic rearrangement and with complete regioselectivity. This coupling, in combination with in situ oxidation by mCPBA, enables the convenient conversion of iodoarenes into desirable biaryls. The obtained biaryls have convertible iodo and hydroxy groups in close proximity, and are thus synthetically useful, as exemplified by the controlled syntheses of π-extended furans and a substituted [5]helicene. DFT calculations clearly revealed that the rearrangement is sigmatropic, with C-C bond formation and I-O bond cleavage proceeding in a concerted manner. Acetic acid, which was found to be the best solvent for this protocol, renders the iodine atom more cationic and thus accelerates the sigmatropic rearrangement.

16.
Angew Chem Int Ed Engl ; 57(13): 3499-3503, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29411488

RESUMO

The catalytic activation of small neutral molecules followed by the formation of C-C bonds is a highly important method to increase the complexity and/or value of simple starting materials. Reported is an isolable digermyne, a compound with a Ge≡Ge bond, which acts as a precatalyst for the cyclotrimerization of terminal arylacetylenes to afford the corresponding 1,2,4-triarylbenzenes with absolute regioselectivity. The results demonstrate that bespoke main-group-element compounds can catalytically activate and transform small neutral organic molecules and induce the formation of C-C bonds.

17.
Chemistry ; 24(2): 364-368, 2018 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-29193403

RESUMO

Bis(ferrocenyl)germylene Fc*2 Ge: [2; Fc*=2,5-bis(3,5-di-tert-butylphenyl)-1-ferrocenyl] was isolated in the form of red crystals from the reaction of the sterically demanding ferrocenyl lithium dimer (Fc*Li)2 and GeI2 . Bis(ferrocenyl)germylene 2 exhibits extraordinary thermal stability in hydrocarbon solution and the solid state, as well as stable redox behavior. Moreover, it undergoes a ligand-redistribution reaction with GeCl2 ⋅(dioxane) to afford the corresponding chlorogermylene, which was isolated upon coordination with PBu3 .

18.
Chem Commun (Camb) ; 54(5): 519-522, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29265132

RESUMO

Stable digermynes with sterically demanding Bbt (Bbt = 2,6-[CH(SiMe3)2]2-4-[C(SiMe3)3]-C6H2) or Tbb (Tbb = 4-tBu-2,6-[CH(SiMe3)2]2-C6H2) groups underwent [2+2] cycloadditions with terminal alkenes to give the corresponding 1,2-digermacyclobutenes. In the case of the Bbt-substituted digermyne, the reaction was reversible at room temperature, i.e., the 1,2-digermacyclobutene (Ge(ii) species) is susceptible to a facile reductive elimination that affords the corresponding digermyne (Ge(i) species) and the alkene.

19.
Mol Med Rep ; 16(2): 1957-1963, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28627680

RESUMO

Scarring is the inevitable consequence of wound repair, which may cause significant physical and mental pain to patients when excessive. Bone morphogenetic protein­7 (BMP­7) has been proved to inhibit TGF­ß­induced fibrosis in various tissues including dermal papilla cells. However, the effect of BMP­7 on hypertrophic scarring, a common proliferative disorder of dermal fibroblasts, has not been determined. To overcome this problem, the present study established a mouse model of thermal injury to investigate the inhibitory effects of BMP­7 on scar formation. The histological analysis of scar tissues was performed by H&E and Masson's trichrome staining. Western blot assay was used to determine the level changes of related proteins and TUNEL assay was performed to assess the apoptosis of scar tissues. The results demonstrated that BMP­7 promoted wound healing and inhibited scar formation when compared with untreated mice. Collagen deposition and the expression of fibrotic proteins were suppressed in the scar tissues of mice treated with BMP­7. In addition, BMP­7 induced fibroblast apoptosis in scar tissues. Furthermore, activation of the BMP­7/Smad1/5/8 signaling pathway may have been involved in the inhibitory effects of BMP­7 on scar formation. In conclusion, the results of the present study indicate that BMP­7 may inhibit excessive scar formation via activation of the BMP­7/Smad1/5/8 signaling pathway. The results present a potential alternative therapeutic strategy for the treatment of hypertrophic scarring.


Assuntos
Proteína Morfogenética Óssea 7/farmacologia , Cicatriz/metabolismo , Cicatriz/patologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Animais , Apoptose/efeitos dos fármacos , Colágeno/metabolismo , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Temperatura Alta , Humanos , Camundongos Endogâmicos C57BL , Cicatrização/efeitos dos fármacos
20.
Chem Asian J ; 12(12): 1391-1399, 2017 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-28452140

RESUMO

Photochemical carbosilylation of Sc3 N@Ih -C80 with silirane 1 afforded two corresponding [5,6]-adducts, 2 and 3, and a [6,6]-adduct, 4. The structural and electronic properties of these products were characterized by means of spectroscopic, electrochemical, and theoretical methods. The structure of 2 was disclosed by means of single-crystal X-ray crystallographic analysis. Thermal isomerization of 3 to 2 was observed, whereas that of 2 to 3 proceeded less efficiently at 100 °C. Upon heating under the same conditions, adduct 4 underwent facile decomposition to afford Sc3 N@Ih -C80 , or isomerized into small amounts of 2 and 3. The relative stabilities of 2, 3, and 4 were rationalized through the results of theoretical calculations. In contrast, adducts 2, 3, and 4 were stable under the photolytic conditions employed for carbosilylation. The photochemical functionalization of Sc3 N@Ih -C80 represents a convenient synthetic method to obtain thermally labile fullerene-based products.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA