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1.
Org Lett ; 26(13): 2552-2557, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38527028

RESUMEN

Selective functionalization of fullerenes is an important but challenging topic in fullerene chemistry and synthetic chemistry. Here we present the first example of catalytic system-controlled regioselective 1,2- and 1,4-addition reactions for the flexible and efficient synthesis of novel 1,2- and 1,4-carbocycle-fused fullerenes via a palladium-catalyzed decarboxylative carboannulation process.

2.
Org Lett ; 26(7): 1432-1436, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38350149

RESUMEN

An interrupted N-heterocyclic carbene-catalyzed radical coupling strategy is disclosed for efficient alkylation and arylation of [60]fullerene. This novel and general strategy bridges the gap between organocatalytic radical cross-coupling and functionalization of fullerenes. Readily available feedstocks, remarkably broad substrate scope and functional group compatibility, and convenient late-stage nanomodification of complex molecules make this strategy with incomparable diversity and practicality in the synthesis of monoalkylated and -arylated fullerenes.

3.
Angew Chem Int Ed Engl ; 62(46): e202313074, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37789646

RESUMEN

Herein, we report divergent additions of 2,2'-diazidobiphenyls to C60 and Sc3 N@Ih -C80 . In stark contrast to that of the previously reported bis-azide additions, the unexpected cascade reaction leads to the dearomative formation of azafulleroids 2 fused with a 7-6-5-membered ring system in the case of C60 . In contrast, the corresponding reaction with Sc3 N@Ih -C80 switches to the C-H insertion pathway, thereby resulting in multiple isomers, including a carbazole-derived [6,6]-azametallofulleroid 3 and a [5,6]-azametallofulleroid 4 and an unusual 1,2,3,6-tetrahydropyrrolo[3,2-c]carbazole-derived metallofullerene 5, whose molecular structures have been unambiguously determined by single-crystal X-ray diffraction analyses. Among them, the addition type of 5 is observed for the first time in all reported additions of azides to fullerenes. Furthermore, unexpected isomerizations from 3 to 5 and from 4 to 5 have been discovered, providing the first examples of the isomerization of an azafulleroid to a carbazole-derived fullerene rather than an aziridinofullerene. In particular, the isomerism of the [5,6]-isomer 4 to the [5,6]-isomer 5 is unprecedented in fullerene chemistry, contradicting the present understanding that isomerization generally occurs between [5,6]- and [6,6]-isomers. Control experiments have been carried out to rationalize the reaction mechanism. Furthermore, representative azafulleroids have been applied in organic solar cells, thereby resulting in improved power conversion efficiencies.

4.
J Org Chem ; 88(18): 13076-13088, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37651613

RESUMEN

An unexpected copper-mediated radical-induced ring-opening relay cascade carboannulation reaction of [60]fullerene with cyclobutanone oxime esters is presented for the preparation of various Cl-/Br-incorporated [60]fullerene-fused cyclopentanes. The unique relay cascade transformation uses inexpensive copper salts as promoters and halogen sources and features simple redox-neutral conditions and a broad substrate scope, providing a practical access to a class of novel five-membered carbocycle-fused fullerenes.

5.
BMC Anesthesiol ; 23(1): 161, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37161305

RESUMEN

OBJECTIVE: To investigate the effects of ultrasound-guided erector spinae plane block (ESPB) on acute and chronic post-surgical pain in patients underwent video-assisted thoracoscopic lobectomy. METHODS: A total of 94 patients, who underwent elective unilateral video-assisted thoracoscopic lobotomy from August 2021 to December 2021 were randomly divided into general anesthesia group (group A, n = 46) and ESPB combined with general anesthesia group (group B, n = 48) by computer. Patient controlled intravenous analgesia(PCIA) was performed in both groups after operation. The numerical rating scale(NRS) of rest and cough pain at post anesthesia care unit(PACU), 2 h, 6 h, 12 h, 24 and 48 h after operation, frequency of PCIA in 24 h after operation, frequency of rescue analgesia, patient satisfaction, adverse reactions and complications were recorded in the two groups. Incidence of chronic pain at 3 months and 6 months after operation, the effect of daily life and rating of chronic pain management measures were recorded in the two groups. RESULTS: Compared with group A, rest and cough NRS score at 2 h, 6 h, 12 h, 24 and 48 h after surgery, frequency of PCIA use at 24 h after surgery, frequency of rescue analgesia were significantly decreased in group B (P < 0.05). There was no significant difference in NRS scores of rest and cough at PACU after operation between 2 groups after surgery at post anesthesia care unit (P > 0.05). There were no significant differences in the incidence of postoperative chronic pain between the 2 groups(P > 0.05);The effect of postoperative chronic pain on daily life and pain management measures in group B were significantly lower than those in group A(P < 0.05). Compared with group A, patients in group B had higher satisfaction degree, lower incidence of postoperative nausea and vomiting(PONV), and lower incidence of agitation during anesthesia recovery (P < 0.05). There were no pneumothorax, hematoma and toxicity of local anesthetic in the 2 groups. CONCLUSION: Ultrasound-guided erector spinae plane block can significantly reduce acute post-surgical pain, can not reduce the incidence of chronic post-surgical pain, but can significantly reduce the severity of chronic pain in patients underwent video-assisted thoracoscopic lobectomy. TRIAL REGISTRATION: ChiCTR2100050313,date of registration:26/08/2021.


Asunto(s)
Dolor Agudo , Anestesia de Conducción , Dolor Crónico , Bloqueo Nervioso , Psicocirugía , Humanos , Tos , Estudios Prospectivos , Cirugía Torácica Asistida por Video , Dolor Postoperatorio/prevención & control , Analgesia Controlada por el Paciente , Ultrasonografía Intervencional
6.
Org Lett ; 24(49): 9102-9106, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-36475859

RESUMEN

Herein, a concise and robust approach for the highly efficient assembly of [60]fullerene-fused tricyclic scaffolds has been developed through a palladium-catalyzed cascade [2 + 2 + 2] annulation process. Diverse tricyclic scaffolds incorporating various ring sizes (6-19 membered) and types (carbocycles and N- and O-heterocycles) can be expediently constructed in a single-step transformation.


Asunto(s)
Fulerenos , Paladio , Catálisis
7.
Org Lett ; 24(20): 3691-3695, 2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35576614

RESUMEN

A novel N-heterocyclic carbene-catalyzed three-component umpolung hydroalkylation of [60]fullerene with 4-(chloromethyl)-benzaldehydes/α,ß-unsaturated aldehydes and alcohols/thioalcohols has been developed for the flexible and efficient preparation of diverse monoalkylated hydrofullerenes. Organic catalysis, broad substrate scope, excellent functional group tolerance, and products with high diversity and complexity levels are attractive features of this protocol.

8.
J Org Chem ; 87(5): 3104-3113, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35078312

RESUMEN

Herein, an unprecedented transformation of [60]fullerene with ferrocene compounds giving access to various [60]fullerene-fused bicyclo[2.2.1]hept-5-enes is presented. In the presence of an acid, ferrocene compounds undergo an unusual dissociation process and serve as Diels-Alder diene equivalents to react with [60]fullerene for the selective construction of a class of novel fullerene-fused bridged carbocyclic derivatives. The reaction is easy to perform and has a wide substrate scope as well as excellent functional group compatibility, representing a new application of ferrocene compounds in synthetic chemistry.

9.
Artículo en Inglés | MEDLINE | ID: mdl-34130205

RESUMEN

Due to the strong background interferences in the low-mass region and poor reproducibility of conventional organic matrices, it is of great importance to develop a novel matrix for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to qualitatively and quantitatively analyze small molecules. In this work, water-soluble fullerenol C60(OH)24-26 was selected as a MALDI matrix for the analysis of low-molecular-weight compounds in consideration of optical absorption property, water solubility and stability. Compared with the traditional matrices, fullerenol demonstrated lower background interference and stronger peak intensity. In addition, the hydrophilic fullerenol could avoid the heterogeneous crystallization in sample preparation, increase the reproducibility and sensitivity of MALDI-MS, and ameliorate quantitative analysis of small molecules. With saccharin as model analyte, quantitative analysis was carried out using fullerenol as matrix. The results demonstrated satisfying reproducibility and good tolerance to salt. The limit-of-detection of the quantitative analysis was as low as 4 pmol, and the linear range is 1-100 µg mL-1 with R2 greater than 0.99. The analytical results also showed excellent precision and accuracy, low matrix effect and good recovery rate. Fullerenol as a potential matrix was further validated in the quantification of saccharin sodium in different real food samples, such as nuts and drinks. This work not only confirms the potential of fullerenol for the quantitative analysis in food field, but also provides a new technique for rapid analysis of small molecules.


Asunto(s)
Análisis de los Alimentos/métodos , Fulerenos/química , Sacarina/análisis , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bebidas/análisis , Límite de Detección , Modelos Lineales , Nueces/química , Reproducibilidad de los Resultados
10.
Org Lett ; 23(5): 1775-1781, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33576632

RESUMEN

The first example of metal-free-catalyzed multicomponent annulation reaction of [60]fullerene has been developed for concise and efficient construction of novel [60]fullerene-fused 1,2-tetrahydrocarbazoles. Using inexpensive and readily available I2 as a catalyst, [60]fullerene, ketones, and indoles undergo a formal [2+2+2] annulation process to conveniently assemble diverse 1,2-tetrahydrocarbazoles. Mechanistic studies indicate that this reaction proceeds through I2-promoted generation of a 3-vinylindole structure with the characteristics of a conjugated diene followed by cycloaddition to [60]fullerene.

11.
Chem Commun (Camb) ; 57(1): 49-52, 2021 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-33244545

RESUMEN

Herein a new, general and practical method for the spirocyclization of [60]fullerene through a palladium-catalyzed domino Heck/C-H activation reaction is presented. A wide range of novel [60]fullerene-fused spirocyclic derivatives can be easily and flexibly synthesized with a broad substrate scope and excellent functional-group tolerance. A plausible mechanism involving an alkyl Pd(ii) species as a key intermediate has been proposed.

12.
Org Lett ; 22(18): 7327-7332, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-32897079

RESUMEN

Herein an unprecedented iron(II)-catalyzed redox-neutral radical cascade reaction of [60]fullerene with γ,δ-unsaturated oxime esters is reported for the preparation of novel free (N-H) pyrrolidino[2',3':1,2]fullerenes. The transformation undergoes an intramolecular cyclization/intermolecular cyclization/oxidation/hydrolysis cascade, and features simple operation, broad substrate scope/high functional group compatibility as well as suitable for scale-up synthesis, providing a facile and practical access to a range of free pyrrolidino[2',3':1,2]fullerenes.

13.
Org Lett ; 22(1): 284-289, 2020 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-31845811

RESUMEN

The first example of transition-metal catalyzed multicomponent carboannulation of [60]fullerene has been developed. [60]Fullerene, 2-(2,3-allenyl)malonates, and (hetero)aryl iodides undergo a Pd(0)-catalyzed tandem coupling-carboannulation process for regioselective access to novel polysubstituted [60]fullerene-fused cyclopentane derivatives with a wide range of substrate scope and high functional group compatibility. A plausible mechanism involving the formation of a fullerene-π-allylpalladium complex with the characteristic of a fullerene cation as a key intermediate has been proposed.

14.
Chem Commun (Camb) ; 55(96): 14498-14501, 2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31729498

RESUMEN

A general and practical methodology for the preparation of novel vinyl-substituted [60]fullerene-fused tetrahydrofurans/pyrans/quinolines through palladium-catalyzed decarboxylative heterocyclizations of [60]fullerene with vinylethylene/2-alkylidenetrimethylene carbonates and vinyl carbamates was developed. Without additives or ligands, the Pd(PPh3)4-catalyzed transformations undergo decarboxylative O- and N-heteroannulation processes to efficiently furnish structurally diverse [60]fullerene-fused heterocyclic derivatives.

15.
Org Lett ; 21(16): 6461-6465, 2019 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-31373207

RESUMEN

Reported herein is a new copper-catalyzed N-H/C-H sequential relay oxidative radical carboannulation of [60]fullerene with C2-functionalized free indoles for the direct construction of novel [60]fullerene-fused tetrahydrocyclopenta[b]indoles. The transformation shows high regioselectivity and atom economy, broad substrate scope, and good functional group tolerance, providing an efficient and practical approach to access diversely substituted fullerene-fused polycyclic derivatives from simple hydrocarbons.

16.
J Org Chem ; 84(11): 7255-7264, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31094189

RESUMEN

Cu(II)/Mn(III)-mediated synergistic radical N-heteroannulation reaction of [60]fullerene with N-sulfonylated o-amino-arylmalonates has been developed for the direct and efficient construction of [60]fullerene-fused tetrahydroquinoline derivatives. A plausible mechanism for the formation of fullerotetrahydroquinolines is proposed, and the electrochemical properties of the obtained fullerene adducts are investigated.

17.
Int J Clin Exp Pathol ; 12(11): 4125-4129, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31933809

RESUMEN

Early diagnosis is important to improve the prognosis of pancreatic cancer (PC). Identifying potential biomarkers is essential for the monitoring and treatment of PC. The long noncoding RNA (lncRNA) UFC1 has been identified as an oncogenic factor in many cancers. However, the expression of UFC1 and its potential role in diagnosis and prognosis of PC remain largely unknown. The present study aimed to investigate the role of serum UFC1 in diagnosis and prognosis. The results indicated that serum UFC1 expression was relatively higher in PC patients than that in healthy volunteers. ROC curve analysis revealed that the serum UFC1 levels could distinguish PC patients from healthy controls, with an AUC value of 0.810. In addition, the serum UFC1 expression level was associated with lymph nodes metastasis, distant metastasis, and clinical stage. Kaplan-Meier analysis indicated that patients with high UFC1 expression exhibited shorter progression-free survival (PFS) and overall survival (OS) than those with low UFC1 expression. Multivariate analysis demonstrated that clinical stage and UFC1 expression level were significant, independent prognostic factors in PC patients. Our data demonstrate that serum UFC1 might serve as a potential biomarker for diagnosis and prognosis of PC.

18.
Chem Commun (Camb) ; 54(95): 13331-13334, 2018 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-30351311

RESUMEN

Described here is the first example of solvent-promoted catalyst-free N-incorporation multicomponent domino reaction for the direct construction of novel π-extension [60]fullerene-fused dihydrocarbolines from simple hydrocarbons. This unprecedented transformation is proposed to proceed by a sequential N-incorporation/[4+2] cycloaddition/elimination process, involving multiple types of bond cleavage and formation in a single chemical operation. Mechanistic studies uncover that solvent is crucial for the success of the transformation, and multiple solvent-aided deprotonation and proton transfer are involved as key steps.

19.
Org Lett ; 20(16): 4801-4805, 2018 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-30052460

RESUMEN

The first umpolung strategy for the cycloacylation of fullerene using a N-heterocyclic carbene organocatalyst is reported. The coupling of [60]fullerene with different structural α,ß-unsaturated aldehydes efficiently furnishes interesting [60]fullerene-fused cyclopentan-1-ones or cyclohex-2-en-1-ones in good to excellent yields. This new reaction displays a wide substrate scope and excellent functional-group tolerance, and diverse substituents such as aryl, heteroaryl, alkenyl, alkyl, and ester can be installed by using the corresponding enals.

20.
J Org Chem ; 83(2): 862-870, 2018 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-29219312

RESUMEN

A novel and efficient Cu(I)/Ag(I)-mediated synergistic annulation reaction of [60]fullerene with diarylethanones, benzoylacetonitriles, and ß-dicarbonyl compounds has been developed for the direct construction of diverse disubstituted dihydrofuran-fused [60]fullerene derivatives. This transformation exhibits a remarkably broad substrate scope and functional group tolerance and provides a useful method to a scarce class of fullerene derivatives.

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