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1.
J Cancer Res Clin Oncol ; 149(14): 13279-13300, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37481754

RESUMO

PURPOSE: Primary mixed adeno-neuroendocrine carcinoma (MANEC) and primary signet-ring cell cancer (SRCC) are two rare but highly malignant tumors in colorectal cancer. Therefore, we attempted to compare the tumors' survival outcomes, identify risk factors, and ultimately evaluate the prognosis by developing a nomogram. METHODS: We identified 755 MANEC and 5836 SRCC patients of colorectal cancer. PSM was used to balance the influence of baseline clinical and pathological differences. Kaplan-Meier method was used to compare the prognosis of different pathological grades and AJCC stages. Cox proportional hazards model was used to identify potential prognostic factors for the two groups. Finally, we developed a nomogram and evaluated the feasibility of the model. RESULTS: After PSM, the median OS and CSS of MANEC patients were significantly better than those of SRCC patients in stage III-IV (P < 0.001) but similar in stage I-II. The median OS and CSS of MANEC patients in each pathological grade were also greater than those of SRCC patients. Patients with MANEC and SRCC who underwent lymph node dissection in more than four areas had longer survival time. MANEC patients benefited from postoperative chemotherapy and radiotherapy; among SRCC patients, those who received preoperative and postoperative comprehensive chemotherapy and radiotherapy had benefits in OS and CSS. CONCLUSION: Both MANEC and SRCC are often diagnosed in advanced stages, highlighting the importance of early screening. Despite the better prognosis of MANEC compared to SRCC, both types of patients require the formulation of personalized treatment strategies based on different risk factors combined with column charts.

2.
Microorganisms ; 11(5)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37317138

RESUMO

[Background] Bacillus LFB112 is a strain of Bacillus amyloliquefaciens screened in our laboratory. Previous studies found that it has a strong ability for fatty acid metabolism and can improve the lipid metabolism of broilers when used as feed additives. [Methods] This study aimed to confirm the fatty acid metabolism of Bacillus LFB112. Sterilized soybean oil (SSO) was added to the Beef Peptone Yeast (BPY) medium, and its effect on fatty acid content in the supernatant and bacteria, as well as expression levels of genes related to fatty acid metabolism, were studied. The control group was the original culture medium without oil. [Results] Acetic acid produced by the SSO group of Bacillus LFB112 decreased, but the content of unsaturated fatty acids increased. The 1.6% SSO group significantly increased the contents of pyruvate and acetyl-CoA in the pellets. Furthermore, the mRNA levels of enzymes involved in the type II fatty acid synthesis pathway of FabD, FabH, FabG, FabZ, FabI, and FabF were up-regulated. [Conclusions] Soybean oil increased the content of acetyl-CoA in Bacillus LFB112, activated its type II fatty acid synthesis pathway, and improved the fatty acid metabolism level of Bacillus LFB112. These intriguing results pave the way for further investigations into the intricate interplay between Bacillus LFB112 and fatty acid metabolism, with potential applications in animal nutrition and feed additive development.

3.
Microorganisms ; 11(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36677423

RESUMO

The aim of this study was to apply a strategy to express a recombinant CLP peptide and explore its application as a product derived from natural compounds. The amphiphilic CLP peptide was hybridized from three parent peptides (CM4, LL37, and TP5) and was considered to have potent endotoxin-neutralizing activity with minimal cytotoxic and hemolytic activity. To achieve high secretion expression, an expression vector of pPICZαA-HSA-CLP was constructed by the golden gate cloning strategy before being transformed into Pichia pastoris and integrated into the genome. The recombinant CLP was purified through the Ni-NTA affinity chromatography and analyzed by SDS-PAGE and mass spectrometry. The Limulus amebocyte lysate (LAL) test exhibited that the hybrid peptide CLP inhibited lipopolysaccharides (LPS) in a dose-dependent manner and was significantly (p < 0.05) more efficient compared to the parent peptides. In addition, it essentially diminished (p < 0.05) the levels of nitric oxide and pro-inflammatory cytokines (including TNF-α, IL6, and IL-1ß) in LPS-induced mouse RAW264.7 macrophages. As an attendant to the control and the parental peptide LL37, the number of LPS-induced apoptotic cells was diminished compared to the control parental peptide LL37 (p < 0.05) with the treatment of CLP. Consequently, we concluded that the hybrid peptide CLP might be used as a therapeutic agent.

4.
BMC Gastroenterol ; 23(1): 22, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36681801

RESUMO

BACKGROUND: N7-methylguanosine (m7G) is present in a wide variety of organisms and has important roles. m7G has been reported to be involved in multiple biological processes, and recent studies have reported that changes in RNA modifications result in tumor cellular transformation and cancer, such as colon adenocarcinoma, lung cancer, and intrahepatic cholangiocarcinoma. However, little is known about the function of the m7G in colon adenocarcinoma. METHODS: We established two clusters based on the expression of all genes associated with m7G to explore the expression pattern of 31 key regulatory factors of m7G RNA and assess the prognostic value of regulatory factors. Wilcoxon test and differential box line plots were applied for bioinformatics analysis. Receiver Operating and Kaplan‒Meier curves were utilized to evaluate the prognostic value. Finally, four genes' expression in the colon cancer cell line was confirmed by qRT-PCR. RESULTS: From The Cancer Genome Atlas database, we found that the expression levels of 25 out of the 31 key N7-methylguanosine RNA modification regulators were significantly different in colon adenocarcinoma. According to 25 methylation regulators' expression, we identified two subgroups by consensus clustering, in which the prognosis was worse in Group 2 than in Group 1 and was significantly correlated with age. Cluster 2 was significantly enriched in tumor-associated pathways, and immune cells were highly infiltrated in Cluster 1 but weakly infiltrated in Cluster 2. Further results indicated that this risk profile may serve as a standalone predictive factor for colon adenocarcinoma, and the four genetic risk profiles' prognostic relatedness was successfully verified through Gene Expression Omnibus dataset. At last, A nomogram for prognosis was created according to age, sex, histological grading, clinicopathological staging, and hazard score to accurately predict patient prognosis in colon adenocarcinoma. We successfully validated the differential expression of four genes using qRT-PCR. CONCLUSIONS: In the present study, we revealed the important contribution of key regulators associated with m7G RNA modifications based on all gene expression in colon adenocarcinoma and developed a signature of risk that serves as a promising prognostic marker for patients with colon adenocarcinoma.


Assuntos
Adenocarcinoma , Neoplasias dos Ductos Biliares , Neoplasias do Colo , Humanos , Neoplasias do Colo/genética , Prognóstico , Adenocarcinoma/genética , Ductos Biliares Intra-Hepáticos , Expressão Gênica
5.
Int J Mol Sci ; 23(3)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35163165

RESUMO

Recently, the drawbacks arising from the overuse of antibiotics have drawn growing public attention. Among them, drug-resistance (DR) and even multidrug-resistance (MDR) pose significant challenges in clinical practice. As a representative of a DR or MDR pathogen, Staphylococcus aureus can cause diversity of infections related to different organs, and can survive or adapt to the diverse hostile environments by switching into other phenotypes, including biofilm and small colony variants (SCVs), with altered physiologic or metabolic characteristics. In this review, we briefly describe the development of the DR/MDR as well as the classical mechanisms (accumulation of the resistant genes). Moreover, we use multidimensional scaling analysis to evaluate the MDR relevant hotspots in the recent published reports. Furthermore, we mainly focus on the possible non-classical resistance mechanisms triggered by the two important alternative phenotypes of the S. aureus, biofilm and SCVs, which are fundamentally caused by the different global regulation of the S. aureus population, such as the main quorum-sensing (QS) and agr system and its coordinated regulated factors, such as the SarA family proteins and the alternative sigma factor σB (SigB). Both the biofilm and the SCVs are able to escape from the host immune response, and resist the therapeutic effects of antibiotics through the physical or the biological barriers, and become less sensitive to some antibiotics by the dormant state with the limited metabolisms.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Farmacorresistência Bacteriana/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Animais , Proteínas de Bactérias/genética , Biofilmes/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica , Humanos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade
6.
Molecules ; 26(23)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34885732

RESUMO

CLP is a novel hybrid peptide derived from CM4, LL37 and TP5, with significantly reduced hemolytic activity and increased antibacterial activity than parental antimicrobial peptides. To avoid host toxicity and obtain high-level bio-production of CLP, we established a His-tagged SUMO fusion expression system in Escherichia coli. The fusion protein can be purified using a Nickel column, cleaved by TEV protease, and further purified in flow-through of the Nickel column. As a result, the recombinant CLP with a yield of 27.56 mg/L and a purity of 93.6% was obtained. The purified CLP exhibits potent antimicrobial activity against gram+ and gram- bacteria. Furthermore, the result of propidium iodide staining and scanning electron microscopy (SEM) showed that CLP can induce the membrane permeabilization and cell death of Enterotoxigenic Escherichia coli (ETEC) K88. The analysis of thermal stability results showed that the antibacterial activity of CLP decreases slightly below 70 °C for 30 min. However, when the temperature was above 70 °C, the antibacterial activity was significantly decreased. In addition, the antibacterial activity of CLP was stable in the pH range from 4.0 to 9.0; however, when pH was below 4.0 and over 9.0, the activity of CLP decreased significantly. In the presence of various proteases, such as pepsin, papain, trypsin and proteinase K, the antibacterial activity of CLP remained above 46.2%. In summary, this study not only provides an effective strategy for high-level production of antimicrobial peptides and evaluates the interference factors that affect the biological activity of hybrid peptide CLP, but also paves the way for further exploration of the treatment of multidrug-resistant bacterial infections.


Assuntos
Antibacterianos/química , Peptídeos Antimicrobianos/química , Peptídeos/química , Proteínas Recombinantes de Fusão/genética , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Antimicrobianos/biossíntese , Peptídeos Antimicrobianos/genética , Peptídeos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Catelicidinas/química , Catelicidinas/genética , Escherichia coli/genética , Hemólise/efeitos dos fármacos , Humanos , Peptídeos/genética , Peptídeos/farmacologia , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/farmacologia
7.
Antibiotics (Basel) ; 10(11)2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34827365

RESUMO

This study aimed to investigate the effects of Bacillus amyloliquefaciens LFB112 on the growth performance, carcass traits, immune response, and serum biochemical parameters of broiler chickens. A total of 396 1 day old, mixed-sex commercial Ross 308 broilers with similar body weights were allotted into six treatment groups. The assigned groups were the CON group (basal diet with no supplement), AB (antibiotics) group (basal diet + 150 mg of aureomycin/kg), C+M group (basal diet + 5 × 108 CFU/kg B. amyloliquefaciens LFB112 powder with vegetative cells + metabolites), C group (basal diet + 5 × 108 CFU/kg B. amyloliquefaciens LFB112 vegetative cell powder with removed metabolites), M group (basal diet + 5 × 108 CFU/kg B. amyloliquefaciens LFB112 metabolite powder with removed vegetative cells), and CICC group (basal diet + 5 × 108 CFU/kg Bacillus subtilis CICC 20179). Results indicated that chickens in the C+M, C, and M groups had higher body weight (BW) and average daily gain (ADG) (p < 0.05) and lower feed conversion ratio (FCR) (p = 0.02) compared to the CON group. The C+M group showed the lowest abdominal fat rate compared to those in the CON, AB, and CICC groups (p < 0.05). Compared to the CON group, serum IgA and IgG levels in the C+M, C, and M groups significantly increased while declining in the AB group (p < 0.05). B. amyloliquefaciens LFB112 supplementation significantly reduced the serum triglyceride, cholesterol, urea, and creatinine levels, while increasing the serum glucose and total protein (p < 0.05). In conclusion, B. amyloliquefaciens LFB112 significantly improved the growth performance, carcass traits, immunity, and blood chemical indices of broiler chickens and may be used as an efficient broiler feed supplement.

8.
Biotechniques ; 71(2): 445-450, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34374327

RESUMO

The development of a quick, single-step cloning system for generation of multiexon gene expression constructs is presented. The system allows efficient and cost-effective assembly of multiple exons of interest genes into different expression plasmids in both Escherichia coli and Pichia pastoris. The high cloning efficiency and low cost of the system make it ideal for a novel workflow for the assembly of intron-bearing genes for expression in two different expression hosts.


Assuntos
Escherichia coli , Pichia , Transcriptoma , Clonagem Molecular , DNA , Escherichia coli/genética , Éxons , Vetores Genéticos , Genômica , Pichia/genética , Plasmídeos/genética , Proteínas Recombinantes/genética , Saccharomycetales
9.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(6): 687-691, 2020 Dec 01.
Artigo em Chinês | MEDLINE | ID: mdl-33377348

RESUMO

The application of artificial intelligence in medicine has gradually received attention along with its development. Many studies have shown that machine learning has a wide range of applications in stomatology, especially in the clinical diagnosis and treatment of maxillofacial cysts and tumors. This article reviews the application of machine learning in maxillofacial cyst and tumor to provide a new method for the diagnosis of oral and maxillofacial diseases.


Assuntos
Cistos , Medicina Bucal , Inteligência Artificial , Cistos/diagnóstico , Humanos , Aprendizado de Máquina
10.
Front Immunol ; 11: 1361, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695115

RESUMO

Intestinal inflammation can cause impaired epithelial barrier function and disrupt immune homeostasis, which increases the risks of developing many highly fatal diseases. Enterohemorrhagic Escherichia coli (EHEC) O157:H7 causes intestinal infections worldwide and is a major pathogen that induces intestinal inflammation. Various antibacterial peptides have been described as having the potential to suppress and treat pathogen-induced intestinal inflammation. Cecropin A (1-8)-LL37 (17-30) (C-L), a novel hybrid peptide designed in our laboratory that combines the active center of C with the core functional region of L, shows superior antibacterial properties and minimized cytotoxicity compared to its parental peptides. Herein, to examine whether C-L could inhibit pathogen-induced intestinal inflammation, we investigated the anti-inflammatory effects of C-L in EHEC O157:H7-infected mice. C-L treatment improved the microbiota composition and microbial community balance in mouse intestines. The hybrid peptide exhibited improved anti-inflammatory effects than did the antibiotic, enrofloxacin. Hybrid peptide treated infected mice demonstrated reduced clinical signs of inflammation, reduced weight loss, reduced expression of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interferon-gamma (IFN-γ)], reduced apoptosis, and reduced markers of jejunal epithelial barrier function. The peptide also affected the MyD88-nuclear factor κB signaling pathway, thereby modulating inflammatory responses upon EHEC stimulation. Collectively, these findings suggest that the novel hybrid peptide C-L could be developed into a new anti-inflammatory agent for use in animals or humans.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Cecropinas/farmacologia , Infecções por Escherichia coli/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Animais , Escherichia coli O157 , Feminino , Inflamação/microbiologia , Inflamação/patologia , Enteropatias/microbiologia , Enteropatias/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/farmacologia , Catelicidinas
11.
Artigo em Inglês | MEDLINE | ID: mdl-32582649

RESUMO

CATH-2TP5 is a linear cationic hybrid peptide, consequent from naturally occurring antimicrobial peptide (AMPs) Cathelicidin-2 (CATH-2) and Immunomodulatory peptide Thymopentin (TP5) having dynamic and potent anti-inflammatory activities without hemolytic effect. The biocompatible mechanism of CATH-2TP5 is favored to explore new methodologies in the direction of biomedical applications. In this retrospectively study, an antiendotoxin and anti-inflammatory hybrid peptide CATH-2TP5 was emulated into pPICZα-A and successfully expressed in Pichia pastoris (P. pastoris). The recombinant CATH-2TP5 was purified through the Ni-affinity column and reversed-phase HPLC. The purified CATH-2TP5 peptide exhibited robust anti-endotoxin activity and significantly (p < 0.05) neutralized the effect of lipopolysaccharide (LPS). Furthermore, the down-regulated effect of CATH-2TP was more pronounced (p < 0.05) on LPS-induced cytotoxic effects, nitric oxide secretion and pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß) in murine RAW264.7 macrophages. As associated to control and parental peptide the number of apoptotic cells was also contracted with the treatment of CATH-2TP5. Thus, we concluded that CATH-2TP5 peptide may be used in various biomedical applications as a therapeutic drug.

12.
Int J Mol Sci ; 20(24)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817671

RESUMO

Immunity is a defensive response that fights disease by identifying and destroying harmful substances or microbiological toxins. Several factors, including work-related stress, pollution, and immunosuppressive agents, contribute to low immunity and poor health. Native peptides, a new class of immunoregulatory agents, have the potential for treating immunodeficiencies, malignancies, and infections. However, the potential cytotoxicity and low immunoregulatory activity and stability of native peptides have prevented their development. Therefore, we designed three hybrid peptides (LTAa, LTAb, and LTAc) by combining a characteristic fragment of LL-37 with an active Tα1 center that included Tα1 (17-24), Tα1 (20-25), and Tα1 (20-27). The best hybrid peptide (LTAa), according to molecule docking and in vitro experiments, had improved immunoregulatory activity and stability with minimal cytotoxicity. We investigated the immunoregulatory effects and mechanisms of LTAa using a cyclophosphamide-immunosuppressed murine model. LTAa effectively reversed immunosuppression by enhancing immune organ development, activating peritoneal macrophage phagocytosis, regulating T lymphocyte subsets, and increasing cytokine (tumor necrosis factor-alpha, interleukin-6, and interleukin-1ß) and immunoglobulin (IgA, IgG, and IgM) contents. The immunomodulatory effects of LTAa may be associated with binding to the TLR4/MD-2 complex and activation of the NF-κB signaling pathway. Therefore, LTAa could be an effective therapeutic agent for improving immune function.


Assuntos
Fatores Imunológicos/síntese química , Fatores Imunológicos/farmacologia , Peptídeos/síntese química , Peptídeos/farmacologia , Animais , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Fatores Imunológicos/química , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/química , Células RAW 264.7
13.
Front Immunol ; 10: 1841, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447849

RESUMO

Intestinal inflammatory disorders, such as inflammatory bowel disease (IBD), are associated with increased pro-inflammatory cytokine secretion in the intestines. Furthermore, intestinal inflammation increases the risk of enteric cancer, which is a common malignancy globally. Native anti-inflammatory peptides are a class of anti-inflammatory agents that could be used in the treatment of several intestinal inflammation conditions. However, potential cytotoxicity, and poor anti-inflammatory activity have prevented their development as anti-inflammatory agents. Therefore, in this study, we designed and developed a novel hybrid peptide for the treatment of intestinal inflammation. Eight hybrid peptides were designed by combining the active centers of antimicrobial peptides, including LL-37 (13-36), YW12D, innate defense regulator 1, and cathelicidin 2 (1-13) with thymopentin or the active center of thymosin alpha 1 (Tα1) (17-24). The hybrid peptide, LL-37-Tα1 (LTA), had improved anti-inflammatory activity with minimal cytotoxicity. LTA was screened by molecule docking and in vitro experiments. Likewise, its anti-inflammatory effects and mechanisms were also evaluated using a lipopolysaccharide (LPS)-induced intestinal inflammation murine model. The results showed that LTA prevented LPS-induced impairment in the jejunum epithelium tissues and infiltration of leukocytes, which are both histological markers of inflammation. Additionally, LTA decreased the levels of tumor necrosis factor-alpha, interferon-gamma, interleukin-6, and interleukin-1ß. LTA increased the expression of zonula occludens-1 and occludin, and reduced permeability and apoptosis in the jejunum of LPS-treated mice. Additionally, its anti-inflammatory effect is associated with neutralizing LPS, binding to the Toll-like receptor 4-myeloid differentiation factor 2 (TLR4/MD-2) complex, and modulating the nuclear factor-kappa B signal transduction pathway. The findings of this study suggest that LTA may be an effective therapeutic agent in the treatment of intestinal inflammation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Desenho de Fármacos , Desenvolvimento de Medicamentos , Inflamação/tratamento farmacológico , Enteropatias/tratamento farmacológico , Animais , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Citocinas/antagonistas & inibidores , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , NF-kappa B/fisiologia , Peptídeos/uso terapêutico , Células RAW 264.7 , Timalfasina/uso terapêutico , Junções Íntimas/efeitos dos fármacos , Catelicidinas
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3666-3672, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946672

RESUMO

Cleft lip and palate is the most common congenital malformation in oral and maxillofacial region. As a kind of facial plastic surgery, the most important factor for the success of cleft lip and palate repair surgery is the design of surgical markers and incisions. However, general hospitals especially in rural areas lack dependable medical resources, which makes the effect of the surgery hard to guarantee. To solve this problem, we propose a novel robotic surgery assistant technology based on deep learning to help reduce the technical threshold and improve the overall effect of cleft lip and palate repair surgery. For the first time, a robust dataset of cleft lip and palate cases is established, which can be used to train the model to locate surgical markers and incisions. Secondly, we build a strong baseline on this dataset by using state-of-the-art Hourglass architecture and residual learning, with two neoteric block designs, one of which enables stronger capability of generalization, while the other greatly reduces the complexity of the model, thus making efficient application possible. Finally, by comparing with other facial feature extraction methods, our models achieve the best results on multiple metrics, showing their strong superiority and adaptability on this task.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Aprendizado Profundo , Procedimentos Cirúrgicos Bucais , Procedimentos Cirúrgicos Robóticos , Humanos
15.
J Org Chem ; 77(22): 10369-74, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23067042

RESUMO

A convenient one-pot approach for the synthesis of aryl sulfides through the coupling of thiols with Grignard reagents in the presence of N-chlorosuccinimide is described. The sulfenylchlorides were formed when thiols were treated with N-chlorosuccinimide, and the resulting sulfenylchlorides were then directly reacted with Grignard reagents to provide aryl sulfides in good to excellent yields under mild reaction conditions. Functional groups including ester, fluoro, and chloro are tolerated by the reaction conditions employed. It is important to note that this method has a short reaction time (30 min in total) and represents an alternative approach for the synthesis of aryl sulfides over the existing protocols.


Assuntos
Reagentes de Ligações Cruzadas/química , Indicadores e Reagentes/química , Succinimidas/química , Compostos de Sulfidrila/química , Sulfetos/síntese química , Catálise , Estrutura Molecular , Sulfetos/química
16.
Chem Commun (Camb) ; 48(67): 8440-2, 2012 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-22797474

RESUMO

We report here the regioselective synthesis of aryl chalcogenides through the iridium-catalyzed meta C-H borylation followed by copper-catalyzed C-S coupling reaction with chalcogenide sources in one pot, giving the 3,5-disubstituted aryl chalcogenides with high regioselectivity and good yields.


Assuntos
Calcogênios/síntese química , Irídio/química , Catálise , Calcogênios/química , Estrutura Molecular , Estereoisomerismo
17.
J Org Chem ; 77(14): 6100-6, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22708836

RESUMO

We report here the iron-catalyzed cross-coupling reaction of alkyl vinyl halides with thiols. While many works are devoted to the coupling of thiols with alkyl vinyl iodides, interestingly, the known S-vinylation of vinyl bromides and chlorides is limited to 1-(2-bromovinyl)benzene and 1-(2-chlorovinyl)benzene. Investigation on the coupling reaction of challenging alkyl vinyl bromides and chlorides with thiols is rare. Since the coupling of 1-(2-bromovinyl)benzene and 1-(2-chlorovinyl)benzene with thiols can be performed in the absence of any catalyst, here we focus on the coupling of thiols with alkyl vinyl halides. This system is generally reactive for alkyl vinyl iodides and bromides to provide the products in good yields. 1-(Chloromethylidene)-4-tert-butyl-cyclohexane was also coupled with thiols, giving the targets in moderate yields.


Assuntos
Cloretos/química , Reagentes de Ligações Cruzadas/síntese química , Compostos Férricos/química , Compostos de Sulfidrila/química , Sulfetos/síntese química , Compostos de Vinila/química , Catálise , Reagentes de Ligações Cruzadas/química , Estrutura Molecular , Sulfetos/química
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