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1.
BMC Surg ; 23(1): 349, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37974183

RESUMO

BACKGROUND: Laparoscopic pancreaticoduodenectomy(LPD) has become the goal of lots of minimally invasive surgical centers in recent years. Postoperative pancreatic fistula(POPF) is still the barrier to attaining the above goal. Thus, improving anastomosis techniques to reduce the rate of POPF has been a hotspot of surgery. Blumgart pancreaticojejunostomy is considered one of the best anastomosis procedures, with low rates of POPF. However, the original Blumgart pancreaticojejunostomy method is not easy for laparoscopic operation. In consequence, we modified a Blumgart pancreaticojejunostomy technique with a simple and practicable procedure and applied to LPD. METHODS: We collected and retrospectively analyzed the perioperative clinical data of patients who underwent modified Blumgart anastomosis from February 2017 to September 2022. The above patients included 53 cases in open pancreaticojejunostomy(OPD) and 58 cases in LPD. After propensity score matching, 44 cases were included for comparison in each group. RESULTS: After propensity score matching, the average time for pancreaticojejunostomy was about 30 min in the LPD group. The Clinically relevant POPF(CR-POPF) rate was 9.1%. The length of postoperative hospitalization was 13.1 days. Compared with the OPD group, The CR-POPF rate in the LPD group are not significant differences. But the postoperative length of hospital stay was significantly shorter in the LPD group. Besides, there were no other severely postoperative complications between two groups. CONCLUSION: The modified Blumgart anastomosis technique applied to LPD in our Center not only has simple and convenient properties but also low rate of CR-POPF. And this method may be a good choice for surgeons to begin to carry out LPD.


Assuntos
Laparoscopia , Pancreaticoduodenectomia , Humanos , Pancreaticoduodenectomia/métodos , Estudos Retrospectivos , Anastomose Cirúrgica/métodos , Pancreaticojejunostomia/métodos , Fístula Pancreática/etiologia , Laparoscopia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia
2.
Phytochemistry ; 213: 113786, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37422009

RESUMO

Medicinal plants constitute a source for designing clinically useful drugs targeting diseases through various mechanisms. Plant secondary metabolites can be used as lead compounds of drugs. Corynanthe alkaloids are highly abundant natural bioactive substances of various core structures possessing important properties such as nerve excitation and antimalarial and analgesic effects. In this review, we summarize and review the state-of-the-art corynanthe-type alkaloid research focusing on phytochemistry, pharmacology, and structural chemistry. Approximately 120 articles reporting 231 alkaloids classified into simple corynanthe, yohimbine, oxindole corynanthe, mavacurane, sarpagine, akuammiline, strychnos, and ajmaline-type groups were compiled. Relevant biological properties discussed include antiviral, antibacterial, anti-inflammatory, antimalarial, muscle-relaxant, vasorelaxant, and analgesic activities and activities affecting the main nervous and cardiac systems, as well as NF-κB inhibitory and Na+-glucose cotransporter inhibitory properties. This review provides insights and a reference for future studies, thus paving the way for the discovery of drugs based on corynanthe alkaloids.


Assuntos
Alcaloides , Antimaláricos , Plantas Medicinais , Pausinystalia , Alcaloides/farmacologia , Analgésicos/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
3.
Head Neck ; 45(9): 2161-2172, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37466293

RESUMO

BACKGROUND: Cysteine-rich protein 2 (CSRP2) is discovered as oncogene. The study aims to investigate the clinical significance and potential mechanism of CSRP2 in head and neck squamous cell carcinoma (HNSCC). METHODS: CSRP2 expression was explored by immunohistochemistry tissue microarrays and Western blotting in HNSCC. The effect of CSRP2 on the cancer stemness and epithelial-to-mesenchymal transition (EMT) of HNSCC cells was investigated by sphere formation, wound healing, and transwell assays. The vitro and vivo experiments revealed that CSRP2 modulated cancer stemness and EMT phenotypes in HNSCC. RESULTS: CSRP2 was overexpressed in HNSCC patients and presented poor prognosis. CSRP2 knockdown inhibited the migration and invasion ability of the HNSCC cells. And CSRP2 expression was closely associated with CSCs markers, EMT-transcription factor, new oncoprotein, and immune checkpoint. CONCLUSION: The overexpression of CSRP2 indicates poor prognosis and plays a key role in maintaining the cancer cell stemness and EMT.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/genética , Fatores de Transcrição/genética , Fenótipo , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteínas Musculares/farmacologia , Proteínas Nucleares/genética , Proteínas com Domínio LIM/genética
4.
Molecules ; 28(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36903273

RESUMO

There is a lack of information on the compound profile of Cornus officinalis Sieb. et Zucc. seeds. This greatly affects their optimal utilization. In our preliminary study, we found that the extract of the seeds displayed a strong positive reaction to the FeCl3 solution, indicating the presence of polyphenols. However, to date, only nine polyphenols have been isolated. In this study, HPLC-ESI-MS/MS was employed to fully reveal the polyphenol profile of the seed extracts. A total of 90 polyphenols were identified. They were classified into nine brevifolincarboxyl tannins and their derivatives, 34 ellagitannins, 21 gallotannins, and 26 phenolic acids and their derivatives. Most of these were first identified from the seeds of C. officinalis. More importantly, five new types of tannins were reported for the first time: brevifolincarboxyl-trigalloyl-hexoside, digalloyl-dehydrohexahydroxydiphenoyl (DHHDP)-hexdside, galloyl-DHHDP-hexoside, DHHDP-hexahydroxydiphenoyl(HHDP)-galloyl-gluconic acid, and peroxide product of DHHDP-trigalloylhexoside. Moreover, the total phenolic content was as high as 79,157 ± 563 mg gallic acid equivalent per 100 g in the seeds extract. The results of this study not only enrich the structure database of tannins, but also provide invaluable aid to its further utilization in industries.


Assuntos
Cornus , Medicamentos de Ervas Chinesas , Taninos/química , Cornus/química , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Taninos Hidrolisáveis , Polifenóis , Sementes , Medicamentos de Ervas Chinesas/química
5.
Insect Sci ; 30(4): 1165-1182, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36377192

RESUMO

The Japanese pine sawyer, Monochamus saltuarius, as a beetle vector of Bursaphelenchus xylophilus (pine wood nematode), is an economically important forest pest in Eurasia. To feed on the phloem and xylem of conifers, M. saltuarius needs to overcome various stress factors, including coping with entomopathogenic bacteria and also various plant secondary compounds (PSCs). As an important adaptation strategy to colonize host trees, M. saltuarius deposit eggs in oviposition pits to shield their progeny. These pits harbor bacterial communities that are involved in the host adaptation of M. saltuarius to the conifers. However, the composition, origin, and functions of these oviposition pit bacteria are rarely understood. In this study, we investigated the bacterial community associated with M. saltuarius oviposition pits and their ability to degrade PSCs. Results showed that the bacterial community structure of M. saltuarius oviposition pits significantly differed from that of uninfected phloem. Also, the oviposition pit bacteria were predicted to be enriched in PSC degradation pathways. The microbial community also harbored a lethal strain of Serratia, which was significantly inhibited. Meanwhile, metatranscriptome analysis indicated that genes involved in PSCs degradation were expressed complementarily among the microbial communities of oviposition pits and secretions. In vitro degradation showed that bacteria cultured from oviposition pits degraded more monoterpenes and flavonoids than bacteria cultured from uninfected phloem isolates. Disinfection of oviposition pits increased the mortality of newly hatched larvae and resulted in a significant decrease in body weight in the early stages. Overall, our results reveal that M. saltuarius construct oviposition pits that harbor a diverse microbial community, with stronger PSCs degradation abilities and a low abundance of entomopathogenic bacteria, resulting in the increased fitness of newly hatched larvae.


Assuntos
Besouros , Pinus , Feminino , Animais , Besouros/microbiologia , Larva , Serratia , Árvores , Monoterpenos , Pinus/microbiologia
6.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2457-2465, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36131662

RESUMO

Meteorological disaster is one of the main factors restricting agriculture development in China. It is important to clarify the risk of summer maize agrometeorological disaster for disaster prevention and mitigation. Based on the natural disaster risk theory, we collected meteorological data and maize yield data from 1981 to 2018 in a typical area in the northern mountainous area of Sichuan Basin (Wangcang County). The main disaster-causing factors affecting summer maize production were determined. A comprehensive agro-meteorological disaster risk assessment model for summer maize was constructed in combination with the sensitivity of pregnant environment and vulnerability of disaster bearing to evaluate the agrometeorological disasters risk of summer maize production in the northern mountainous area of Sichuan Basin. The results showed that during the study period, high temperature in mature period, rainstorm in flowering period, rainstorm in mature period, continuous rain in filling period and drought in booting stage were the main agrometeorological disasters affecting the growth and development of summer maize. The agrometeorological disaster risk of maize generally distributed in a southwest-northeast pattern, with the distribution areas of high-risk and higher-risk areas accounting for half of the total area of Wangcang County. The high-risk areas were mainly located in the southwest of the county, which was basically consistent with the high-value areas of hazard-pregnant environment sensitivity. The low-risk areas were mostly concentrated in the western part of county territory, which were also low-risk areas of high temperature in mature period, rainstorm in mature period, and rainstorm in flowering period disasters.


Assuntos
Desastres , Zea mays , China , Desastres/prevenção & controle , Secas , Sistemas de Informação Geográfica , Medição de Risco
8.
Int J Biol Macromol ; 195: 466-474, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34914909

RESUMO

Periplaneta americana L. (PA), a type of animal medicine, has been widely used for wound healing in clinical settings. In order to further investigate the bioactive wound healing substances in PA, crude PA protein-polysaccharide complexes were further purified by cellulose DE-52 and Sephadex G100 chromatography in succession. Among these isolated fractions, two fractions eluted by 0.3 M and 0.5 M NaCl with the higher yield, respectively named PaPPc2 and PaPPc3 respectively, were chosen for the wound healing experiments. Mediated by HPGPC, amino acid and monosaccharide composition analysis, circular dichroism spectrum, glycosylation type, FT-IR, and 1H NMR analysis, the characterization of PaPPc2 and PaPPc3 was implemented. And then, the benefits of PaPPcs to promote cell proliferation, migration, and tube formation of HUVECs were determined in vitro, indicated these fractions would facilitate angiogenesis. Finally, as proof of concept, PaPPc2 and PaPPc3 were employed to accelerate the acute wounds of diabetic mice, involving in increase blood vessels and the amounts of angiogenesis-related cytokines (α-SMA, VEGF, and CD31). In short, this study provides an experimental basis to demonstrate the protein-polysaccharide complexes of Periplaneta americana L. as its wound healing bioactive substances.


Assuntos
Materiais Biocompatíveis , Proteínas de Insetos/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/farmacologia , Periplaneta/química , Polissacarídeos/química , Cicatrização , Aminoácidos/química , Animais , Linhagem Celular , Fenômenos Químicos , Diabetes Mellitus Experimental , Humanos , Substâncias Macromoleculares/isolamento & purificação , Medicina Tradicional , Camundongos , Monossacarídeos/química , Análise Espectral
9.
Nanomaterials (Basel) ; 13(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36615922

RESUMO

The formation of heterojunction structures can effectively prevent the recombination of photogenerated electron-hole pairs in semiconductors and result in the enhancement of photoelectric properties. Using TiO2 nanotubes (prepared using the hydrothermal-impregnation method) as carriers, CdS-TiO2NTs were fabricated as a photoelectrochemical (PEC) sensor, which can be used under visible light and can exhibit good PEC performance due to the existence of the heterojunction structure. The experimental results show that the prepared CdS-TiO2NTs electrode had a linear response to 2-16 mM glutathione (GSH). The sensor's sensitivity and detection limit (LOD) were 102.9 µA·mM-1 cm-2 and 27.7 µM, respectively. Moreover, the biosensor had good stability, indicating the potential application of this kind of heterojunction PEC biosensor.

10.
Zhongguo Zhong Yao Za Zhi ; 46(10): 2467-2473, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34047092

RESUMO

Plants have a memory function for the environmental stress they have suffered. When they are subjected to repeated environmental stress, they can quickly and better activate the response and adaptation mechanism to environmental stress, thus realizing long-term stable reproduction. However, most of the relevant studies are applied to crops and Arabidopsis thaliana rather than medicinal plants about the improvement of plant growth status and the effect on phytoalexin biosynthesis. In this study, yeast extract(YE) was used as an elicitor to simulate biotic stress, and the changes in biomass and the content of some secondary metabolites were measured by giving repeated stresses to Sorbus aucuparia suspension cell(SASC). The results showed that the accumulation levels of biomass and some secondary metabolites in SASC subjected to repeated stress are significantly increased at some time points compared with single stress. A phenomenon that SASC can memorize biotic stress is confirmed in this study and influences phytoalexin accumulation in SASC. Furthermore, the work laid the groundwork for research into the transgenerational stress memory mechanism of medicinal plant.


Assuntos
Sorbus , Células Cultivadas , Metabolismo Secundário , Estresse Fisiológico
11.
Org Biomol Chem ; 18(35): 6866-6880, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32844859

RESUMO

A series of scarce amino-substituted cyclopentafullerenes instead of the expected N-alkyl-2,5-disubstituted fulleropyrrolidines were synthesized in moderate to excellent yields via the simple one-step reaction of [60]fullerene with cheap and easily available ß-substituted propionaldehydes and secondary amines in the absence/presence of magnesium perchlorate. The in situ generation of allylic amines from ß-substituted propionaldehydes and secondary amines played a crucial role in the successful preparation of amino-substituted cyclopentafullerenes without additional carbons. With the addition of magnesium perchlorate, secondary amines containing ethyl group(s) could produce novel amino-substituted cyclopentafullerenes with two additional carbons. All the obtained cyclopentafullerenes displayed high stereoselectivity with cis isomers as the exclusive or major products. Plausible reaction mechanisms are proposed to elucidate the above-mentioned reaction process.

12.
ACS Appl Mater Interfaces ; 11(24): 21473-21480, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31135127

RESUMO

The inherent instability of UV-induced degradation in TiO2-based perovskite solar cells was largely improved by replacing the anatase-phase compact TiO2 layer with an atomic sheet transport layer (ASTL) of two-dimensional (2D) Ti1-δO2. The vital role of microscopic carrier dynamics that govern the UV stability of perovskite solar cells was comprehensively examined in this work by performing time-resolved pump-probe spectroscopy. In conventional perovskite solar cells, the presence of a UV-active oxygen vacancy in compact TiO2 prohibits current generation by heavily trapping electrons after UV degradation. Conversely, the dominant vacancy type in the 2D Ti1-δO2 ASTL is a titanium vacancy, which is a shallow acceptor and is not UV-sensitive. Therefore, it significantly suppresses carrier recombination and extends UV stability in perovskite solar cells with a 2D Ti1-δO2 ASTL. Other carrier dynamics, such as electron diffusion, electron injection, and hot hole transfer processes, were found to be less affected by UV irradiation. Quantitative pump-probe data clearly show a correlation between the carrier dynamics and UV aging of perovskite solar cells, thus providing a profound insight into the factors driving UV-induced degradation in perovskite solar cells and the origin of its performance.

13.
Angew Chem Int Ed Engl ; 58(15): 4963-4967, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30667570

RESUMO

The preparation of carbon materials usually involves the decomposition of precursors and the reorganization of the as-generated fragments. However, the cleavage of bonds and the simultaneous formation of new bonds at nearly the same positions prevents effective yet precise fabrication. Herein, a supramolecular precursor, cucurbit[6]uril, that contains multiple bonds with distinct bond strengths is proposed to decouple the twin problem of simultaneous bond cleavage and formation, allowing multistage transformations to hierarchical porous carbon and metal-doped carbon in a single yet effective pyrolysis step without the need of a template or additional purification. As a proof-of-concept, the Fe-doped carbon electrocatalysts realized a Pt/C-like half-wave potential of 0.869 V vs. RHE and small Tafel slope of 51.3 mV dec-1 in oxygen reduction reaction.

14.
Zhongguo Zhong Yao Za Zhi ; 43(2): 248-253, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29552840

RESUMO

Studies on the characteristic chemical markers of sulfur fumigation have become an effective auxiliary way for quality control of traditional Chinese medicine. This study established a quantitative analysis method for the determination of p-hydroxybenzyl hydrogen sulfite (p-HS) in Gastrodiae Rhizoma (GR) based on UPLC-MS/MS. Then, 37 batches of GR were screened, and the results showed that 27 batches of them were sulfur-fumigated. Especially, the GR samples in Yunnan producing areas were sulfur-fumigated more seriously. Based on the stability of p-HS after different storage time and heat treatment methods, it was found that the content of p-HS was stable and reliable in the storage period of 8 months and under normal heat treatment (50, 60, 70, 80 °C) conditions. In conclusion, this study shows a high sensitivity, good selectivity and good stability of p-HS, which can provide reference for the quality control and sulfur fumigation screening of GR.


Assuntos
Medicamentos de Ervas Chinesas/normas , Fumigação , Gastrodia/química , Sulfitos/análise , China , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Controle de Qualidade , Rizoma/química , Enxofre , Espectrometria de Massas em Tandem
15.
Zhongguo Zhong Yao Za Zhi ; 43(2): 261-266, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29552842

RESUMO

To study the effect of different storage time on the chemical compositions and sulfur dioxide residues of sulfur-fumigated Gastrodiae Rhizoma (GR), and provide scientific basis for solving the quality and safety issues of sulfur-fumigated traditional Chinese medicinal materials. GR, sulfur-fumigated GR and its medicinal slices were stored under the same conditions, and then 8 active ingredients and sulfur dioxide residues were measured respectively. The results showed that the content of gastrodins in sulfur-fumigated GR and its medicinal slices was significantly lower than that in the non-fumigated GR. Moreover, the content of sulfur dioxide residue in sulfur-fumigated GR was significantly higher than that in its medicinal slices. That is to say, sulfur fumigation degree had significantly higher effect on GR quality as compared with its medicinal slices. During the whole storage time (8 months), the content of the eight chemical components in GR was not changed greatly in general. However, after the storage for 4 months, the content of 8 components and sulfur dioxide residues in all of GR samples were significantly changed. In particular, the content of sulfur dioxide residue in GR medicinal materials decreased up to 50% or more.


Assuntos
Armazenamento de Medicamentos , Medicamentos de Ervas Chinesas/química , Fumigação , Gastrodia/química , Dióxido de Enxofre/análise , Rizoma/química , Enxofre
16.
RSC Adv ; 8(23): 12526-12534, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35541234

RESUMO

In photovoltaic devices, more effective transfer of dissociated electrons and holes from the active layer to the respective electrodes will result in higher fill factors and short-circuit current densities and, thus, enhanced power conversion efficiencies (PCEs). Planar perovskite photovoltaics feature an active layer that can provide a large exciton diffusion length, reaching several micrometers, but require efficient carrier transport layers for charge extraction. In this study, we employed two nanocomposite carrier transfer layers-an electron transport layer (ETL) comprising [6,6]phenyl-C61-butyric acid methyl ester (PC61BM) doped with the small molecule 4,7-diphenyl-1,10-phenanthroline (Bphen), to enhance the electron mobility, and a hole transfer layer (HTL) comprising poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) doped with molybdenum disulfide (MoS2) nanosheets, to enhance the hole mobility. We used ultraviolet photoelectron spectroscopy to determine the energy levels of these composite ETLs and HTLs; atomic force microscopy and scanning electron microscopy to probe their surface structures; and transmission electron microscopy and synchrotron grazing-incidence small-angle X-ray scattering to decipher the structures of the ETLs. Adding a small amount (less than 1%) of Bphen allowed us to tune the energy levels of the ETL and decrease the size of the PC61BM clusters and, therefore, generate more PC61BM aggregation domains to provide more pathways for electron transport, leading to enhanced PCEs of the resulting perovskite devices. We used quantitative pump-probe data to resolve the carrier dynamics from the perovskite to the ETL and HTL, and observed a smaller possibility of carrier recombination and a shorter injection lifetime in the perovskite solar cell doubly modified with carrier transport layers, resulting in an enhancement of the PCE. The PCE reached 16% for a planar inverted perovskite device featuring an ETL incorporating 0.5 wt% Bphen within PC61BM and 0.1 wt% MoS2 within PEDOT:PSS; this PCE is more than 50% higher than the value of 10.2% for the corresponding control device.

17.
ACS Appl Mater Interfaces ; 9(16): 14006-14012, 2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28281352

RESUMO

Ink-printing method emerges as a viable way for manufacturing large-scale flexible Cu(In,Ga)Se2 (CIGS) thin film photovoltaic (TFPV) devices owing to its potential for the rapid process, mass production, and low-cost nonvacuum device fabrication. Here, we brought the femtosecond laser annealing (fs-LA) process into the ink-printing CIGS thin film preparation. The effects of fs-LA treatment on the structural and optoelectronic properties of the ink-printing CIGS thin films were systematically investigated. It was observed that, while the film surface morphology remained essentially unchanged under superheating, the quality of crystallinity was significantly enhanced after the fs-LA treatment. Moreover, a better stoichiometric composition was achieved with an optimized laser scanning rate of the laser beam, presumably due to the much reduced indium segregation phenomena, which is believed to be beneficial in decreasing the defect states of InSe, VSe, and InCu. Consequently, the shunt leakage current and recombination centers were both greatly decreased, resulting in a near 20% enhancement in photovoltaic conversion efficiency.

18.
J Org Chem ; 81(22): 11201-11209, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27766870

RESUMO

The thermal reaction of C60 with aromatic aldehydes and inactive secondary amines for the stereoselective synthesis of trans-1,2,5-trisubstituted fulleropyrrolidines has been developed. Moreover, when an o-hydroxyl group was located at the phenyl ring of the generated fulleropyrrolidines, the Cu(OAc)2-promoted regioselective intramolecular C-O coupling reaction occurred to generate unique tricycle-fused fullerene derivatives.

19.
J Org Chem ; 81(19): 9296-9307, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27654104

RESUMO

The facile one-step reaction of [60]fullerene with aldehydes and primary amines in the presence of cheap and easily available Cu(OAc)2·H2O afforded a series of new types of fulleropyrrolines with trisubstituted C═C bonds in good to excellent yields, which would be difficult to prepare by known methods. The formed fulleropyrroline under the assistance of Pd(OAc)2 and CuCl2·2H2O could be further converted to 1-fulleropyrrolidine by the chlorohydroxylation reaction of C═C bond. Subsequent elimination reaction of 1-fulleropyrrolidine with the aid of TsOH·H2O generated the scarce 1-fulleropyrroline derivative.

20.
J Org Chem ; 81(5): 1769-77, 2016 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-26841702

RESUMO

A series of scarce N-unsubstituted 2,5-diaryl fulleropyrrolidines as cis isomers could be prepared via the facile one-step reaction of [60]fullerene with N-unsubstituted arylmethanamines promoted by cheap and easily available ferric perchlorate. Nevertheless, the reaction of N-substituted arylmethanamines with [60]fullerene under the same conditions gave different experimental results. N-Methylbenzylamine formed N-methyl 2,5-diphenyl fulleropyrrolidine as a trans isomer, and N,N-dibenzylamine unexpectedly afforded the N-unsubstituted 2,5-diphenyl fulleropyrrolidine as a cis isomer. Intriguingly, high stereoselectivity for all 2,5-diaryl fulleropyrrolidines could be observed although both cis and trans isomers were possibly formed. N-Unsubstituted fulleropyrrolidine could be further converted to N-substituted fulleropyrrolidines under the assistance of an acid chloride or an isocyanate. A possible reaction pathway leading to 2,5-diaryl fulleropyrrolidines is also proposed.

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