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Halogen-Bond-Promoted Direct Cross-Coupling of Trifluoromethylated Alkyl Bromides with Coumarins/Quinolinones: Unraveling Trifluoromethyl Effects. Org Lett 2024; 26:3097-3102. [PMID: 38574397 DOI: 10.1021/acs.orglett.4c00717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
This study introduces a novel approach involving XB-mediated cross-coupling of α-trifluoromethylated alkyl bromides with coumarins and quinolinones under visible light irradiation. Both density functional theory (DFT) calculations and experimental studies converge to suggest that the noncovalent interaction between alkyl bromides and DMAP, intensified by the α-trifluoromethyl group, plays a pivotal role in facilitating this chemoselective reaction.
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Trifluoromethyl Rhodium-Carbynoid in [2+1+2] Cycloadditions. Angew Chem Int Ed Engl 2024; 63:e202318887. [PMID: 38237082 DOI: 10.1002/anie.202318887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Indexed: 02/24/2024]
Abstract
Trifluoromethyl cationic carbyne (CF3 C+ :) possessing dual carbene-carbocation behavior emulated as trifluoromethyl metal-carbynoid (CF3 C+ =M) has not been explored yet, and its reaction characteristics are unknown. Herein, a novel α-diazotrifluoroethyl sulfonium salt was prepared and used in Rh-catalyzed three-component [2+1+2] cycloadditions for the first time with commercially available N-fused heteroarenes and nitriles, yielding a series of imidazo[1,5-a] N-heterocycles that are of interest in medicinal chemistry, in which the insertion of trifluoromethyl Rh-carbynoid (CF3 C+ =Rh) into C=N bonds of N-fused heteroarenes was involved. This strategy demonstrates synthetic applications in late-stage modification of pharmaceuticals, construction of CD3 -containing N-heterocycles, gram-scale experiments, and synthesis of phosphodiesterase 10A inhibitor analog. These highly valuable and modifiable imidazo[1,5-a] N-heterocycles exhibit good antitumor activity in vitro, thus demonstrating their potential applications in medicinal chemistry.
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Catalyst-free decarboxylative cross-coupling of N-hydroxyphthalimide esters with tert-butyl 2-(trifluoromethyl)acrylate and its application. Org Biomol Chem 2024; 22:2279-2283. [PMID: 38407278 DOI: 10.1039/d3ob02103c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Here, we demonstrate a practical method toward the facile synthesis of CF3-containing amino acids through visible light promoted decarboxylative cross-coupling of a redox-active ester with tert-butyl 2-(trifluoromethyl)acrylate. The reaction was driven by the photochemical activity of electron donor-acceptor (EDA) complexes that were formed by the non-covalent interaction between a Hantzsch ester and a redox-active ester. The advantages of this protocol are its synthetic simplicity, rich functional group tolerance, and a cost-effective reaction system.
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Backbone N-methylation of peptides: Advances in synthesis and applications in pharmaceutical drug development. Bioorg Chem 2023; 141:106892. [PMID: 37776681 DOI: 10.1016/j.bioorg.2023.106892] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 09/16/2023] [Accepted: 09/25/2023] [Indexed: 10/02/2023]
Abstract
Peptide-based drugs have garnered considerable attention in recent years owing to their increasingly crucial role in the treatment of diverse diseases. However, the limited pharmacokinetic properties of peptides have hindered their full potential. One prominent strategy for enhancing the druggability of peptides is N-methylation, which involves the addition of a methyl group to the nitrogen atom of the peptide backbone. This modification significantly improves the stability, bioavailability, receptor binding affinity and selectivity of peptide drug candidates. In this review, we provide a comprehensive overview of the advancements in synthetic methods for N-methylated peptide synthesis, as well as the associated limitations. Moreover, we explore the versatile effects of N-methylation on various aspects of peptide properties. Furthermore, we emphasize the efforts dedicated to N-methylated peptide pharmaceuticals that have successfully obtained marketing approval.
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Synthesis of Alkylated Polyfluorobenzenes through Decarboxylative Giese Addition of Aliphatic N-Hydroxyphthalimide Esters with Polyfluorostyrene. J Org Chem 2023; 88:14105-14114. [PMID: 37708081 DOI: 10.1021/acs.joc.3c01672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
Polyfluoroaromatic compounds play crucial roles in medicinal and material science. However, the synthesis of alkylated polyfluoroarenes has been relatively underdeveloped. In this study, we devised a novel decarboxylative coupling reaction between aliphatic N-hydroxyphthalimide esters and polyfluorostyrene, leveraging the photochemical activity of electron donor-acceptor (EDA) complexes. This method offers simple reaction conditions, a broad substrate scope, and excellent functional group tolerance. Furthermore, we have demonstrated the practicality of this protocol through late-stage polyfluoroaryl modification of biologically active molecules using readily available carboxylic acids as starting materials, thus providing an important supplement to the current toolbox for accessing alkylated polyfluoroaryl motifs.
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Synthesis of Fluoroalkylated Pyrrolidines through Neat Reaction of Fluoroalkyl Iodides with N, N‐Diallylamines. Adv Synth Catal 2023. [DOI: 10.1002/adsc.202300092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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Photocatalytic Decarboxylative Coupling of Aliphatic N‐hydroxyphthalimide Esters with Bromopolyfluorobenzene. Adv Synth Catal 2023. [DOI: 10.1002/adsc.202201279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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[Proliferative lesions with mesonephric features in the gynecologic tract: a clinicopathological analysis of sixteen cases]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2022; 51:1000-1006. [PMID: 36207913 DOI: 10.3760/cma.j.cn112151-20220209-00088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To investigate the clinicopathological features of proliferations with mesonephric features (PMF) of the gynecologic tract. Methods: A retrospective analysis was performed on the clinical and pathological data of 16 cases with PMF that were diagnosed from October 2016 to January 2022 at a single institution. The relevant literature was reviewed. Results: Among the 16 cases, with an average of 53 years (31-68 years), there were 5 cases of mesonephric hyperplasia, 4 cases of mesonephric adenocarcinoma and 7 cases of mesonephric-like adenocarcinoma. The five cases of mesonephric hyperplasia were located in the lateral wall of the cervix and composed of simple tubules with growth patterns of diffuse or lobular clusters, without obvious stromal reaction. Four cases of mesonephric adenocarcinoma consisted of a mixture of papillary, cribriform, solid and other architectures, the nuclei resembling these of papillary thyroid carcinoma, and strong fibroproliferative reaction. They were located deep in the cervical and vaginal stroma. One of the tumors showed atypical mesonephric hyperplasia adjacent to the tumor. Five uterine and two ovarian mesonephric-like adenocarcinoma cases had similar histological morphology with mesonephric adenocarcinoma, but no mesonephric remnants/mesonephric hyperplasia were found near the tumors. In addition, four (4/5) uterine mesonephric-like adenocarcinoma cases originated from the endometrium with secondary involvement of myometrium, including one case with clear demarcation between the normal endometrium and the neoplastic glands. One (1/5) uterine mesonephric-like adenocarcinoma case was mainly located in the deep myometrium, along with adenomyosis around the tumor, without mesonephric remnants. Two ovarian mesonephric-like adenocarcinoma cases were associated with endometriotic cyst/endometrioid cystadenoma, including one case with an abrupt transition between normal epithelium and atypical mesonephric cells within the single individual cyst directly adjacent to tumor. All mesonephric hyperplasia and mesonephric adenocarcinoma cases were positive for GATA3, PAX8 and CD10 in a varying degree, and negative for ER, PR and TTF1. Although mesonephric-like adenocarcinoma showed a considerable overlap of immunohistochemical expression with mesonephric adenocarcinoma, seven mesonephric-like adenocarcinoma cases were positive for TTF1 and negative for GATA3. Conclusions: PMF is a class of rare proliferative lesions with morphological and immunophenotypic characteristics of mesonephric duct. Its commonly involved site, microscopic morphology, associated benign and/or atypical lesions, and immunophenotype may contribute to its diagnosis and differential diagnosis.
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Visible-light Promoted Cross-coupling of Ethyl Iododifluoroacetate with Silyl Enol Ethers for the Synthesis of β-Fluoroenones via Noncovalent Interactions. Tetrahedron Lett 2022. [DOI: 10.1016/j.tetlet.2022.153782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Synthesis of Secondary Trifluoromethylated Alkyl Bromides Using 2-Bromo-3,3,3-trifluoropropene as a Radical Acceptor. Org Lett 2022; 24:2143-2148. [PMID: 35274952 DOI: 10.1021/acs.orglett.2c00425] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Herein, the first example using commercially available 2-bromo-3,3,3-trifluoropropene (BTP) as a radical acceptor has been reported. Taking advantage of this strategy, a wide range of secondary trifluoromethylated alkyl bromides were synthesized in good to excellent yields with broad functional group tolerance by using redox-active esters as a radical precursor. The practicality of this protocol was further demonstrated by diverse derivations and direct modification of biologically active molecules.
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Tyrosine Sulphation of CXCR4 Induces the Migration of Fibroblast in OSF. Oral Dis 2022; 29:1782-1790. [PMID: 35150031 DOI: 10.1111/odi.14150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 01/12/2022] [Accepted: 02/07/2022] [Indexed: 11/30/2022]
Abstract
Oral submucous fibrosis (OSF) caused by areca nut chewing is a prevalent fibrotic disease in Asia-Pacific countries. Arecoline-induced migration of fibroblasts (FBs) plays a vital role in the development of OSF. However, the specific molecular mechanisms involved remain unclear. Many studies have shown that tyrosine sulphation of chemokines can influence cell migration. Herein, we demonstrated that arecoline stimulates tyrosine sulphation of the chemokine receptor 4 (CXCR4) through the tyrosylprotein sulphotransferase-1 (TPST-1) to enhance the migration ability of FBs. Moreover, by RNA-Seq analysis, we found that the most significantly altered pathway was the EGFR pathway after the arecoline stimulation for FBs. After the knockdown of arecoline-induced EGFR expression, the tyrosine sulphation of CXCR4 was significantly decreased by the inhibition of TPST-1 induction. Finally, in human OSF specimens, TPST-1 expression was directly correlated with the expression of CXCR4. These data indicate that the arecoline-induced tyrosine sulphation of CXCR4, which is regulated by TPST-1, might be a potential mechanism that contributes to FB migration in OSF.
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[Primary endometrial squamous cell carcinoma with endometrial atypical hyperplasia: report of a case]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2022; 51:74-76. [PMID: 34979763 DOI: 10.3760/cma.j.cn112151-20210524-00371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
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Nickel-Catalyzed Cross-Coupling of Amino-Acid-Derived Alkylzinc Reagents with Alkyl Bromides/Chlorides: Access to Diverse Unnatural Amino Acids. Org Lett 2021; 24:240-244. [PMID: 34958223 DOI: 10.1021/acs.orglett.1c03884] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Unnatural α-amino acids are important synthetic targets in the field of peptide science. Herein we report an efficient, versatile, and straightforward strategy for the synthesis of homophenylalanine derivatives via the nickel-catalyzed Csp3-Csp3 cross-coupling of (fluoro)benzyl bromides/chlorides with natural α-amino-acid-derived alkylzinc reagents. The current protocol features the advantages of a low-cost nickel catalyst system, synthetic convenience, and the tolerance of rich functionality and stereochemistry.
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Abstract
We present herein a visible-light-induced [3 + 2] cycloaddition of a hypervalent iodine(III) reagent with α-ketoacids for the construction of 5-CF3-1,3,4-oxadiazoles that are of importance in medicinal chemistry. The reaction proceeds smoothly without a photocatalyst, metal, or additive under mild conditions. Different from the well-established trifluorodiazoethane (CF3CHN2), the diazotrifluoroethyl radical [CF3C(·)N2], a trifluoroethylcarbyne (CF3CĊ:) equivalent and an unusual CF3-containing building block, is involved in the present reaction system.
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Visible-Light-Induced Palladium-Catalyzed Selective Defluoroarylation of Trifluoromethylarenes with Arylboronic Acids. J Am Chem Soc 2021; 143:13971-13979. [PMID: 34411483 DOI: 10.1021/jacs.1c07459] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Selective functionalization of inactive C(sp3)-F bonds to prepare medicinally interesting aryldifluoromethylated compounds remains challenging. One promising route is the transition-metal-catalyzed cross-coupling through oxidative addition of the C(sp3)-F bond in trifluoromethylarenes (ArCF3), which are ideal precursors for this process due to their ready availability and low cost. Here, we report an unprecedented excited-state palladium catalysis strategy for selective defluoroarylation of trifluoromethylarenes with arylboronic acids. This visible-light-induced palladium-catalyzed cross-coupling proceeds under mild reaction conditions and allows transformation of a variety of arylboronic acids and ArCF3. Preliminary mechanistic studies reveal that the oxidative addition of the C(sp3)-F bond in ArCF3 to excited-state palladium(0) via a single electron transfer pathway is responsible for the C(sp3)-F bond activation.
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[A retrospective cohort study of incidence of anemia and risk factors in HIV/AIDS patients with access to antiretroviral therapy in Dehong Jingpo and Dai Autonomous Prefecture in Yunnan province, 2004-2018]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2021; 42:1218-1224. [PMID: 34814534 DOI: 10.3760/cma.j.cn112338-20200602-00799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Objective: To investigate the incidence of anemia and risk factors in HIV/AIDS patients with access to antiretroviral therapy (ART) during 2004-2018 in Dehong Jingpo and Dai Autonomous Prefecture (Dehong). Methods: A retrospective cohort study was conducted in HIV/AIDS patients receiving ART in Dehong during 2004-2018 based on the data extracted from the National HIV/AIDS antiretroviral therapy database. Cox proportional risk model was used to analyze the factors associated with the incidences of anemia and moderate or severe anemia in the HIV/AIDS patients. And the piecewise linear mixed-effects model was used to depict the trajectory of hemoglobin changes over time after initiating ART according to baseline level. Results: A total of 8 044 HIV/AIDS patients were included, in whom 6 337 (78.8%) were without anemia at baseline survey and had a median follow up time of 4.43 (P25, P75: 1.50, 6.71) years. The median follow up time for 1 291 new anemia cases and 293 new moderate or severe anemia cases was 0.16 (P25, P75: 0.07, 1.99) years and 0.48 (P25, P75:0.09, 2.97) years, respectively. The incidence rate of anemia and moderate or severe anemia was 4.40 per 100 person-years and 0.41 per 100 person-years respectively. In multivariable Cox regression analysis, older age, being female, being in Dai and Jingpo ethnic group, baseline BMI <18.5 kg/m2, baseline CD4+T lymphocyte cell counts (CD4) <200 cells/μl, and zidovudine (AZT) -based initial treatment regimen were factors significantly and positively associated with incidence of anemia after treatment. Factors as being female, being in Dai ethnic group, baseline BMI <18.5 kg/m2, mild baseline anemia, and AZT-based initial treatment regimen were significantly and positively associated with incidence of moderate or severe anemia after treatment. Conclusion: The risk for anemia was higher in HIV/AIDS patients with specific characteristics, such as age ≥60 years , being female, being in Dai and Jingpo ethnic groups, lower BMI, CD4 <200 cells/μl, and treatment of AZT, after initiation of ART in Dehong during 2004-2018. Additional efforts are needed to strengthen the screening, prevention and treatment of anemia in this population.
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[Incidence and influencing factors of AIDS-related and non-AIDS-related deaths after receiving antiretroviral therapy among HIV-positive individuals in Dehong Dai and Jingpo Autonomous Prefecture, 2010-2019]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2021; 42:632-637. [PMID: 34814442 DOI: 10.3760/cma.j.cn112338-20200903-01121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Objective: To explore the changing trends and influencing factors of AIDS-related and non-AIDS-related deaths after receiving antiretroviral therapy (ART) among HIV-positive individuals in Dehong Dai Jingpo autonomous prefecture (Dehong) from 2010 to 2019. Methods: Based on the Chinese National treatment database, HIV patients who initiated ART from 2010 to 2019 were included in the analysis. The cumulative incidence function was used to estimate the cumulative incidence of AIDS-related death and non-AIDS-related death, respectively. The Fine-Grey model was used to compare the differences between AIDS-related and non-AIDS-related deaths and analyze its influencing factors. Results: A total of 7 068 HIV-positive individuals were included, of which 388 were AIDS-related deaths and 570 were non-AIDS-related deaths. The cumulative mortality rate at years 1, 2, 3, 4, 5, 7 and 9 after receiving ART were 2.27%, 3.46%, 4.47%, 5.03%, 5.84%, 6.61%, 7.40% for AIDS-related deaths, and 1.63%, 3.11%, 4.68%, 6.02%, 7.42%, 10.49%, 12.75% for non-AIDS-related deaths, respectively. In the Fine-Grey model, older age at ART initiation, male, unmarried, injection drug use as the transmission route, lower baseline BMI, lower baseline CD4+ T cell counts, baseline FIB-4 score >3.25, and baseline anemia were risk factors for AIDS-related death. In contrast, age at ART initiation ≥45 years, male, Dai, and Jingpo minority ethnicities, unmarried, injection drug use as the transmission route, lower baseline BMI, baseline FIB-4 score >3.25, baseline eGFR <60 ml·min-1·1.73 m-2, and baseline anemia were risk factors for non-AIDS-related deaths. Conclusions: The cumulative mortality rate was low among HIV-positive individuals after receiving ART in Dehong during 2010-2019. The mortality of non-AIDS-related deaths was higher than that of AIDS-related deaths. There were also differences in the factors influencing AIDS-related and non-AIDS-related deaths and interventions should be intensified to target the influencing factors for non-AIDS-related deaths.
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Effect of congenital heart disease on the recurrence of cough variant asthma in children. BMC Cardiovasc Disord 2021; 21:130. [PMID: 33691639 PMCID: PMC7949247 DOI: 10.1186/s12872-021-01940-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 03/01/2021] [Indexed: 11/10/2022] Open
Abstract
Background The research into the recurrence of cough variant asthma (CVA) in congenital heart disease (CHD) are few in number. The purpose of this study is to investigate the effect of CHD on the risk of the recurrence of CVA. Methods This study was a retrospective cohort study of 489 children with CVA aged between one and 14 years, of whom 67 had CHD complicated with CVA and 134 had CVA without CHD at a ratio of 1:2 according to age, sex and index year. The adjusted hazard ratio (aHR) of CVA recurrence in both the CHD cohort and the non-CHD cohort was determined by multivariate analysis using the Cox proportional hazard regression model. Results Adjusting for CHD classification, Mycoplasma pneumonia (MP) infection and immunoglobulin E (IgE) sensitization, the recurrence hazard of CVA in the complex congenital heart disease (CCHD) group (aHR = 3.281; 95% CI 1.648–6.530; P < 0.01) was significantly higher than that in the simple congenital heart disease group (aHR = 2.555; 95% CI 1.739–3.752; P < 0.01). Further, children with IgE sensitization (aHR = 2.172; 95% CI 1.482–3.184; P < 0.01) had a higher recurrence hazard of CVA than those without IgE sensitization, and children with MP infection (aHR = 1.777; 95% CI 1.188–2.657; P < 0.01) had a higher recurrence hazard of CVA than those without the MP infection. Conclusion The hazard of recurrent CVA is higher in children with CHD, especially in the CCHD children. In addition, those children with IgE sensitization or a MP infection had an increased hazard of recurrent CVA.
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Using Chlorotrifluoroethane for Trifluoroethylation of (Hetero)aryl Bromides and Chlorides via Nickel Catalysis. Org Lett 2021; 23:1400-1405. [PMID: 33544601 DOI: 10.1021/acs.orglett.1c00058] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A nickel-catalyzed reductive cross-coupling between industrial chemical CF3CH2Cl and (hetero)aryl bromides and chlorides has been reported. The reaction is synthetically simple without the preparation of arylmetals and exhibits high functional group tolerance. The utility of this protocol has been demonstrated by the late-stage modification of pharmaceuticals, providing a facile route for medicinal chemistry.
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Visible light induced deaminative alkylation of difluoroenoxysilanes: a transition metal free strategy. Org Chem Front 2021. [DOI: 10.1039/d1qo00507c] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Visible-light-promoted deaminative alkylation of difluoroenoxysilanes utilizing Hantzsch ester as a catalyst or through substrate-induced pathway have been demonstrated.
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Abstract
Iron-catalyzed functionalization of inert bonds has scarcely been documented.
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Visible light promoted deaminative difluoroalkylation of aliphatic amines with difluoroenoxysilanes. Chem Commun (Camb) 2020; 56:14247-14250. [DOI: 10.1039/d0cc05725h] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A visible light promoted deaminative strategy for the difluoroalkylation reaction utilizing pyridinium-activated aliphatic primary amines and difluoroenoxysilane as substrates has been developed.
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A general and green fluoroalkylation reaction promoted via noncovalent interactions between acetone and fluoroalkyl iodides. Chem Commun (Camb) 2020; 56:1815-1818. [DOI: 10.1039/c9cc09517a] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The first example of visible light promoted fluoroalkylation reactions initiated via noncovalent interactions between solvents and RFI is presented.
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[Cervical invasive stratified mucin-producing carcinoma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2019; 48:984-986. [PMID: 31818079 DOI: 10.3760/cma.j.issn.0529-5807.2019.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Palladium-catalyzed cross-coupling of benzylzinc reagents with 2-bromo-3,3,3-trifluoropropene. SYNTHETIC COMMUN 2019. [DOI: 10.1080/00397911.2019.1663540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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[Association of maternal nocturnal sleep throughout pregnancy with the early nocturnal sleep of infants]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2019; 57:608-613. [PMID: 31352746 DOI: 10.3760/cma.j.issn.0578-1310.2019.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the association between maternal nocturnal sleep during pregnancy and their infants' nocturnal sleep patterns in early infancy by establishing a birth cohort. Methods: In this prospective study,healthy pregnant women and their infants were recruited in Chongqing Health Center for Women and Children from September 2013 to January 2014. A total of 40 healthy pregnant women and their infants were enrolled, and 34 pairs (85%) completed the whole survey. Actiwatch, wearing on the mother's wrist or infant's ankle,was used to monitor nighttime sleep at home for 7 times in total,with 7 consecutive days for each monitoring course. Pregnant women were monitored at 16, 24, 32 weeks gestational age, and were required to finish Pittsburgh Sleep Quality Index (PSQI) scale at the end of each monitoring. Their infants were initially monitored at 14 days after birth, followed by 1(st), 2(nd), and 3(rd) month after birth,with sleep diary recorded by parents. Pearson correlation analysis and multivariate linear regression were used to investigate the potential correlation between these two sleep patterns. Results: The average nocturnal sleep time was (465±53) min throughout pregnancy, with increased trend in the latency of maternal nighttime sleep onset ((30±15), (34±29), (38±30) min) while decreasing of average sleep efficiency ((85±5)%, (84±8)%, (83±8)%). The longest night sleep duration decreased from (382±74) min in the first trimester to (330±83) min in the third trimester (F=4.932, P<0.05), while awakening time after sleep onset (WASO) correspondingly increased from (27±22) min to (53±25) min (F=12.605, P<0.05). In terms of infants, the latency of nighttime sleep onset decreased from (43±33) min on the 14th day to (20±29) min at 3-month of age (t=3.281, P=0.002), while the longest nighttime sleep duration increased from (20±62) min to (265±140) min (t=3.867, P<0.01); meanwhile, the total nocturnal sleep time and the sleep efficiency increased from (373±126) min and (63±28)% to (431±103) min and (75±16)%, respectively (t=2.362, P=0.024; t=2.418, P=0.039, respectively). After adjusting for maternal age and body mass index (BMI), parental educational level and family income, maternal mood, exposure to tobacco and alcohol during pregnancy, method of delivery, as well as infants' gender, feeding patterns and gestational weeks, the regression analysis showed that the total nocturnal sleep time and the longest nighttime sleep duration during pregnancy were positively correlated with the corresponding parameters of their infants at the age of 3 months (B=0.541, 95%CI 0.168-0.914, t=2.882, P=0.005; B=0.310, 95%CI 0.035-0.586, t=2.240, P=0.027, respectively). Conclusions: The total nocturnal sleep time and the longest nighttime sleep duration during pregnancy are positively correlated with the corresponding parameters of their infants in early infancy. Paying more attention to improve maternal sleep quality may facilitate their infants to establish sleep-wake patterns early.
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Visible light promoted fluoroalkylation of alkenes and alkynes using 2-bromophenol as a catalyst. Chem Commun (Camb) 2019; 55:12259-12262. [DOI: 10.1039/c9cc06587c] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A simple, mild and efficient approach for the fluoroalkylation of alkenes and alkynes using 2-bromophenol as a catalyst is presented.
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Palladium-catalyzed cross-coupling of unactivated alkylzinc reagents with 2-bromo-3,3,3-trifluoropropene and its application in the synthesis of fluorinated amino acids. Chem Commun (Camb) 2019; 55:3705-3708. [DOI: 10.1039/c8cc10212k] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A palladium-catalyzed cross-coupling of unactivated alkylzinc reagents with 2-bromo-3,3,3-trifluoropropene (BTP) has been developed, which was used as a key step to prepare a series of trifluoromethylated and difluoromethylated amino acids.
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Catalyst-free and visible light promoted trifluoromethylation and perfluoroalkylation of uracils and cytosines. Chem Commun (Camb) 2018; 54:13662-13665. [PMID: 30382250 DOI: 10.1039/c8cc07759b] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fluoroalkylated enaminones, such as trifluridine and 5-trifluoromethyluracil, have widespread applications in pharmaceuticals and agrochemicals. Although these kinds of pharmaceutical agent often bear CF3 and perfluoroalkyl motifs in the core structure, access to such analogues typically requires multi-step synthesis. Here, we report a mild, metal-free and operationally simple strategy for the direct perfluoroalkylation of uracils, cytosines and pyridinones through a visible-light induced pathway from perfluoroalkyl iodides. This photochemical transformation features synthetic simplicity, mild reaction conditions without any photoredox catalyst, and high functional group tolerance, providing a facile route for applications in medicinal chemistry.
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N -Difluoromethylation of imidazoles and pyrazoles using BrCF 2 PO(OEt) 2 under mild condition. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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33
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Manipulation of intestinal dysbiosis by a bacterial mixture ameliorates loperamide-induced constipation in rats. Benef Microbes 2018; 9:453-464. [PMID: 29633634 DOI: 10.3920/bm2017.0062] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Constipation has a significant influence on quality of life. Patients with constipation have slow waves in their gastrointestinal smooth muscles and less faecal water contents, which are closely associated with down-regulation of the interstitial cells of Cajal (ICC) in the gastrointestinal muscles and the aquaporin protein AQP3 expressed in colon epithelial cells. Recent studies supported that patients with constipation have altered intestinal microbial structures compared with healthy controls. Intestinal dysbiosis might be one possible pathophysiological mechanism causing constipation. Bacterial strains, such as Lactobacillus spp., have shown many beneficial effects on the amelioration of constipation. However, few studies reported the structural changes of intestinal microbiota post-intervention of probiotics. In this study, a bacterial mixture was administrated to rats with loperamide-induced constipation. Effects of the bacterial mixture on small intestine transit (SIT), faecal water content, and the intestinal microbiome in rats were evaluated. Meanwhile, we investigated several factors involved in signalling pathways that regulate function of ICC and expression of AQP3 to discuss the possible underlying molecular mechanisms. Intervention of the bacterial mixture improved SIT and faecal water content in constipated rats. The up-regulation of C-kit/SP signalling pathways in ICC and AQP3 significantly contributed to improvements. These changes were closely associated with the manipulation of intestinal dysbiosis in constipated rats. Furthermore, our results revealed the important role of intestinal microbiota in affecting gut motility through regulation of serotonin biosynthesis. This monoamine neurotransmitter, secreted from enterochromaffin cells, up-regulated both substance P/neurokinin 1 receptors pathway of ICC and the expression of AQP3 in intestinal epithelial cells. Our study suggested that the disrupted microbiome in patients could be a potential therapeutic target for the improvement of constipation.
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[Research progress on the dysfunction of interstitial cells of Cajal in gastrointestinal motlity diseases]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2017; 46:810-812. [PMID: 29136701 DOI: 10.3760/cma.j.issn.0529-5807.2017.11.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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36
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Ru(bpy)3
Cl2
as a Photocatalyst for Visible-Light-Induced Fluoroalkylation of Anilines with BrCF2
CF2
Br: A Facile Route to 2-Bromo-1,1,2,2-tetrafluoroethyl Arenes. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700422] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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37
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Visible-light-mediated direct perfluoroalkylation and trifluoromethylation of free anilines. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.09.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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38
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Visible-Light-Induced Direct Difluoroalkylation of Uracils, Pyridinones, and Coumarins. J Org Chem 2017; 82:910-917. [PMID: 27997214 DOI: 10.1021/acs.joc.6b02316] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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39
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Palladium-Catalyzed Direct Thienylation of Monobromide-Substituted Difluorinated Benzothiadiazoles for Organic Photovoltaics. Synlett 2015. [DOI: 10.1055/s-0035-1560461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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40
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A new phase of phosphorus: the missed tricycle type red phosphorene. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:265301. [PMID: 26053470 DOI: 10.1088/0953-8984/27/26/265301] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We predict a new two-dimensional allotrope of phosphorus, which we call red phosphorene, by restructuring the segments of the previously proposed blue and black phosphorenes. Its atomic and electronic structures as well as the thermodynamic and dynamic stabilities are systematically studied by first-principles calculations. The results indicate that the red phosphorene is dynamically stable and possesses remarkably thermodynamical stability comparable to that of the black one. Because of the sp(3)-hybridization and the formation of a localized lone pair, red phosphorene is a semiconductor with an indirect band gap of about 1.96 eV, which can be effectively modulated by in-plane strains due to its wave-like configuration. We find that the red, black and blue phosphorenes show evident distinction in their layer thicknesses, surface work functions, and possible colors, based on which one can distinguish them in future experiments.
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41
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Effective Resistance to Wheat Stripe Rust in a Region with High Disease Pressure. PLANT DISEASE 2014; 98:891-897. [PMID: 30708850 DOI: 10.1094/pdis-09-13-0909-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Stripe rust is a major fungal disease of wheat. It frequently becomes epidemic in southeastern Gansu province, a stripe rust hot spot in China. Evaluations of wheat germplasm response are crucial for developing cultivars to control the disease. In total, 57 wheat cultivars and lines from Europe and other countries, comprising 36 cultivars with documented stripe rust resistance genes and 21 with unknown genes, were tested annually with multiple races of Puccinia striiformis f. sp. tritici in the field at Tianshui in Gansu province from 1993 to 2013. Seven wheat lines were highly resistant, with infection type (IT) 0 during the entire period; 16 were moderately resistant (IT 0;-2); and 26 were moderately susceptible (IT 0;-4), with low maximum disease severity compared with the susceptible control Huixianhong. 'Strampelli' and 'Libellula', with three and five quantitative trait loci, respectively, for stripe rust resistance have displayed durable resistance in this region for four decades. Ten cultivars, including 'Lantian 15', 'Lantian 26', and 'Lantian 31', with stripe rust resistance derived from European lines, were developed in our breeding program and have made a significant impact on controlling stripe rust in southeastern Gansu. Breeding resistant cultivars with multiple adult-plant resistance genes seems to be a promising strategy in wheat breeding for managing stripe rust in this region and other hot spots.
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Direct Olefination of Fluorinated Benzothiadiazoles: A New Entry to Optoelectronic Materials. Chemistry 2014; 20:4532-6. [DOI: 10.1002/chem.201400075] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Indexed: 12/29/2022]
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44
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Direct (Het)Arylation of Fluorinated Benzothiadiazoles and Benzotriazole with (Het)Aryl Iodides. J Org Chem 2014; 79:1712-8. [DOI: 10.1021/jo402675v] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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45
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Selective thienylation of fluorinated benzothiadiazoles and benzotriazoles for organic photovoltaics. Chem Sci 2014. [DOI: 10.1039/c3sc53119h] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
An unprecedented example for the selective synthesis of an FBT–thiophene structural motif via dual C–H functionalization, catalyzed by palladium, has been developed.
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46
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Thioether-Promoted Direct Olefination of Polyfluoroarenes Catalyzed by Palladium. Org Lett 2013; 15:5266-9. [DOI: 10.1021/ol402492s] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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47
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Nickel-Catalyzedortho-Selective Hydrodefluorination ofN-Containing Heterocycle-Polyfluoroarenes. CHINESE J CHEM 2013. [DOI: 10.1002/cjoc.201300327] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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48
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Palladium-CatalyzedOrtho-Selective CF Activation of Polyfluoroarenes with Triethylsilane: A Facile Access to Partially Fluorinated Aromatics. Angew Chem Int Ed Engl 2013; 52:5813-7. [DOI: 10.1002/anie.201300400] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 02/27/2013] [Indexed: 11/08/2022]
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49
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Palladium-CatalyzedOrtho-Selective CF Activation of Polyfluoroarenes with Triethylsilane: A Facile Access to Partially Fluorinated Aromatics. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201300400] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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50
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