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1.
J Org Chem ; 88(18): 13076-13088, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37651613

RESUMO

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.

2.
BMC Anesthesiol ; 23(1): 161, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161305

RESUMO

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.


Assuntos
Dor Aguda , Anestesia por Condução , Dor Crônica , Bloqueio Nervoso , Psicocirurgia , Humanos , Tosse , Estudos Prospectivos , Cirurgia Torácica Vídeoassistida , Dor Pós-Operatória/prevenção & controle , Analgesia Controlada pelo Paciente , Ultrassonografia de Intervenção
3.
Angew Chem Int Ed Engl ; 62(46): e202313074, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37789646

RESUMO

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 ; 87(5): 3104-3113, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35078312

RESUMO

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.

5.
J Org Chem ; 84(11): 7255-7264, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31094189

RESUMO

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.

6.
J Org Chem ; 83(2): 862-870, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29219312

RESUMO

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.

7.
J Org Chem ; 82(12): 6125-6132, 2017 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-28516766

RESUMO

A novel in situ generated TEMPO oxoammonium salt mediated one-pot tandem reaction has been developed for the straightforward construction of pyrrolin-4-ones from readily available ß-oxoamides with amine hydrochlorides. The reaction tolerates various functional groups and represents a reliable method for the synthesis of highly substituted pyrrolin-4-ones in good yields under mild conditions. Detailed mechanistic studies disclosed that TEMPO oxoammonium salt generated in situ was crucial for the transformation involving the formation of enaminone precursors in situ by condensation of the ß-oxoamides with amines, followed by sequential oxidative coupling with ß-oxoamides, intramolecular cyclization, and 1,2-alkyl migration steps.

8.
J Org Chem ; 80(24): 11986-92, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26595850

RESUMO

The rare fulleroxazolidines 2 were successfully synthesized by the facile ferric perchlorate promoted reaction of [60]fullerene with various N-sulfonyl aldimines 1. Further functionalization of fulleroxazolidines by arenes in the presence of boron trifluoride afforded 1,4-bisarylation products 4. A possible reaction mechanism for the formation of the fulleroxazolidines is proposed.

9.
J Org Chem ; 79(22): 11084-90, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25321858

RESUMO

A novel FeCl2·4H2O-mediated internal-oxidant relay cascade reaction has been developed by functionalization of O-substituted benzohydroxamic acids or N-chloro-arylamides with [60]fullerene. Depending on the nature of the N-substituted groups, fullerenooxazoles or rare hydroxyfullerenyl amides could be obtained in a straightforward and flexible manner. Such a new transformation provides a unique strategy for the synthesis of fullerenooxazoles or hydroxyfullerenyl amides.

10.
Org Lett ; 26(7): 1432-1436, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38350149

RESUMO

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.

11.
Org Lett ; 26(13): 2552-2557, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38527028

RESUMO

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.

12.
J Am Chem Soc ; 134(29): 11956-9, 2012 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-22788866

RESUMO

The reaction of an organic azide with an endohedral metallofullerene has been investigated for the first time. Isomeric [5,6]- and [6,6]-azafulleroids can be obtained from the thermal reaction of Sc(3)N@I(h)-C(80) with 4-isopropoxyphenyl azide, while photoirradiation leads exclusively to the [6,6]-azafulleroid. An unprecedented thermal interconversion between the two isomeric azafulleroids has also been discovered.

13.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 32(1): 47-9, 2012 Jan.
Artigo em Zh | MEDLINE | ID: mdl-22500391

RESUMO

OBJECTIVE: To observe the prophylactic effects of senna extract 40 mg/kg on chemotherapy-induced constipation. METHODS: Eighty-two patients suffering from constipation after chemotherapy were assigned to Group AB and Group BA. Group AB referred to patients who first took senna extract in the 1st chemotherapeutic course and the crude fiber diet in the 2nd chemotherapeutic course. But the sequence was just the opposite in Group BA. The effective rates of relieving chemotherapy-induced constipation by senna extract and by the crude fiber diet were observed. The differences of the digestive tract reaction and the hematotoxicity reaction were compared. The conditions of patients' abdominal pain and stool properties were observed after they took senna extract. RESULTS: The effective rate of constipation by taking senna extract was 92.68% and that by the crude fiber diet was 10.93%, with statistical difference shown (P < 0.01). There was no statistic difference in adverse reaction rate such as decreased neutrophils over degree II, decreased hemoglobin, decreased platelet, nausea, vomit, etc. (P > 0.05). The occurrence rate of abdominal pain over degree II after taking senna was 8.54%. In the distribution of stool properties, the rate of loose stool was 35.53%. CONCLUSION: Senna extract 40 mg/kg was effective and safe in treating chemotherapy-induced constipation.


Assuntos
Constipação Intestinal/prevenção & controle , Medicamentos de Ervas Chinesas/uso terapêutico , Extrato de Senna/uso terapêutico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Constipação Intestinal/induzido quimicamente , Estudos Cross-Over , Medicamentos de Ervas Chinesas/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Org Lett ; 24(20): 3691-3695, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35576614

RESUMO

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.

15.
Org Lett ; 24(49): 9102-9106, 2022 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-36475859

RESUMO

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.


Assuntos
Fulerenos , Paládio , Catálise
16.
Org Lett ; 23(5): 1775-1781, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33576632

RESUMO

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.

17.
Chem Commun (Camb) ; 57(1): 49-52, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33244545

RESUMO

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.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34130205

RESUMO

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.


Assuntos
Análise de Alimentos/métodos , Fulerenos/química , Sacarina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bebidas/análise , Limite de Detecção , Modelos Lineares , Nozes/química , Reprodutibilidade dos Testes
19.
Org Lett ; 22(1): 284-289, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31845811

RESUMO

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.

20.
Org Lett ; 22(18): 7327-7332, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32897079

RESUMO

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.

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