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1.
Chemistry ; 30(9): e202303556, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38092708

ABSTRACT

The urgent need to develop a sustainable and environmentally friendly method for synthesizing organophosphine compounds is underscored by their extensive applications in organic synthesis, coordination chemistry, medicinal chemistry, and photoelectric materials. Metalated covalent organic frameworks (MCOFs), which seamlessly integrate the inherent photo properties of COF with the catalytic capabilities of metal ions, offer an optimal material for efficient transformation of organics sustainably. In this study, we introduce a simple COF with nickel anchorages (Bpy-COF-NiCl2 ) as a unimolecular metallaphotocatalytic system for effective C-P bond formation. This heterogeneous photocatalyst exhibits superior catalytic performance, achieving yields of up to 95 %, and demonstrates broad substrate tolerance and functional group reactivity. Notably, the metallaphotocatalytic system has demonstrated the capability to process aryl bromides to produce the desired product, a feat not previously reported. Finally, the production and reusability test at the gram scale attests to its superior practicality for designing future organic cross-coupling reactions.

2.
PLoS One ; 18(9): e0291598, 2023.
Article in English | MEDLINE | ID: mdl-37713442

ABSTRACT

Metabolic suppression in the ischemic heart is characterized by reduced levels of NAD+ and ATP. Since NAD+ is required for most metabolic processes that generate ATP, we hypothesized that nicotinamide restores ischemic tissue NAD+ and improves cardiac function in cardiomyocytes and isolated hearts, and enhances survival in a mouse model of cardiac arrest. Mouse cardiomyocytes were exposed to 30 min simulated ischemia and 90 min reperfusion. NAD+ content dropped 40% by the end of ischemia compared to pre-ischemia. Treatment with 100 µM nicotinamide (NAM) at the start of reperfusion completely restored the cellular level of NAD+ at 15 min of reperfusion. This rescue of NAD+ depletion was associated with improved contractile recovery as early as 10 min post-reperfusion. In a mouse model of cardiac arrest, 100 mg/kg NAM administered IV immediately after cardiopulmonary resuscitation resulted in 100% survival at 4 h as compared to 50% in the saline group. In an isolated rat heart model, the effect of NAM on cardiac function was measured for 20 min following 18 min global ischemia. Rate pressure product was reduced by 26% in the control group following arrest. Cardiac contractile function was completely recovered with NAM treatment given at the start of reperfusion. NAM restored tissue NAD+ and enhanced production of lactate and ATP, while reducing glucose diversion to sorbitol in the heart. We conclude that NAM can rapidly restore cardiac NAD+ following ischemia and enhance glycolysis and contractile recovery, with improved survival in a mouse model of cardiac arrest.


Subject(s)
Heart Arrest , NAD , Rats , Animals , Mice , Rodentia , Heart Arrest/drug therapy , Myocytes, Cardiac , Disease Models, Animal , Lactic Acid , Niacinamide/pharmacology , Adenosine Triphosphate
3.
J Clin Invest ; 133(9)2023 05 01.
Article in English | MEDLINE | ID: mdl-37115695

ABSTRACT

Out-of-hospital cardiac arrest is a leading cause of death in the US, with a mortality rate over 90%. Preclinical studies demonstrate that cooling during cardiopulmonary resuscitation (CPR) is highly beneficial, but can be challenging to implement clinically. No medications exist for improving long-term cardiac arrest survival. We have developed a 20-amino acid peptide, TAT-PHLPP9c, that mimics cooling protection by enhancing AKT activation via PH domain leucine-rich repeat phosphatase 1 (PHLPP1) inhibition. Complementary studies were conducted in mouse and swine. C57BL/6 mice were randomized into blinded saline control and peptide-treatment groups. Following a 12-minute asystolic arrest, TAT-PHLPP9c was administered intravenously during CPR and significantly improved the return of spontaneous circulation, mean arterial blood pressure and cerebral blood flow, cardiac and neurological function, and survival (4 hour and 5 day). It inhibited PHLPP-NHERF1 binding, enhanced AKT but not PKC phosphorylation, decreased pyruvate dehydrogenase phosphorylation and sorbitol production, and increased ATP generation in heart and brain. TAT-PHLPP9c treatment also reduced plasma taurine and glutamate concentrations after resuscitation. The protective benefit of TAT-PHLPP9c was validated in a swine cardiac arrest model of ventricular fibrillation. In conclusion, TAT-PHLPP9c may improve neurologically intact cardiac arrest survival without the need for physical cooling.


Subject(s)
Cardiopulmonary Resuscitation , Cell-Penetrating Peptides , Heart Arrest , Mice , Animals , Swine , Cardiopulmonary Resuscitation/adverse effects , Proto-Oncogene Proteins c-akt/metabolism , Mice, Inbred C57BL , Heart Arrest/therapy , Heart Arrest/etiology , Heart Arrest/metabolism , Disease Models, Animal
4.
Am J Physiol Heart Circ Physiol ; 320(5): H2034-H2043, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33834871

ABSTRACT

We have recently shown that pharmacologic inhibition of PTEN significantly increases cardiac arrest survival in a mouse model, however, this protection required pretreatment 30 min before the arrest. To improve the onset of PTEN inhibition during cardiac arrest treatment, we have designed a TAT fused cell-permeable peptide (TAT-PTEN9c) based on the C-terminal PDZ binding motif of PTEN for rapid tissue delivery and protection. Western blot analysis demonstrated that TAT-PTEN9c peptide significantly enhanced Akt activation in mouse cardiomyocytes in a concentration- and time-dependent manner. Mice were subjected to 8 min asystolic arrest followed by CPR, and 30 mice with successful CPR were then randomly assigned to receive either saline or TAT-PTEN9c treatment. Survival was significantly increased in TAT-PTEN9c-treated mice compared with that of saline control at 4 h after CPR. The treated mice had increased Akt phosphorylation at 30 min resuscitation with significantly decreased sorbitol content in heart or brain tissues and reduced release of taurine and glutamate in blood, suggesting improved glucose metabolism. In an isolated rat heart Langendorff model, direct effects of TAT-PTEN9c on cardiac function were measured for 20 min following 20 min global ischemia. Rate pressure product was reduced by >20% for both TAT vehicle and nontreatment groups following arrest. Cardiac contractile function was completely recovered with TAT-PTEN9c treatment given at the start of reperfusion. We conclude that TAT-PTEN9c enhances Akt activation and decreases glucose shunting to the polyol pathway in critical organs, thereby preventing osmotic injury and early cardiovascular collapse and death.NEW & NOTEWORTHY We have designed a cell-permeable peptide, TAT-PTEN9c, to improve cardiac arrest survival. It blocked endogenous PTEN binding to its adaptor and enhanced Akt signaling in mouse cardiomyocytes. It improved mouse survival after cardiac arrest, which is related to improved glucose metabolism and reduced glucose shunting to sorbitol in critical organs.


Subject(s)
Cardiotonic Agents/therapeutic use , Heart Arrest/drug therapy , Myocardial Reperfusion Injury/drug therapy , PTEN Phosphohydrolase/antagonists & inhibitors , Animals , Brain/metabolism , Cardiotonic Agents/pharmacology , Disease Models, Animal , Glutamic Acid/blood , Heart Arrest/metabolism , Mice , Myocardial Reperfusion Injury/metabolism , Myocardium/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Taurine/blood
5.
Chem Commun (Camb) ; 55(2): 249-252, 2018 Dec 20.
Article in English | MEDLINE | ID: mdl-30534725

ABSTRACT

An asymmetric [3+2] cycloaddition of C,N-cyclic azomethine imines with α,ß-unsaturated 2-acyl imidazoles catalyzed by a chiral-at-metal rhodium complex has been developed. The corresponding C-1-substituted tetrahydroisoquinoline derivatives were obtained in high yields (>90%) with excellent stereoselectivities (up to 99% ee and >20 : 1 dr). The reaction can be conducted on a gram-scale using a low catalyst loading (0.5 mol%) with high yield and selectivity.

6.
Chem Commun (Camb) ; 53(54): 7665-7668, 2017 Jul 04.
Article in English | MEDLINE | ID: mdl-28643839

ABSTRACT

We report an efficient enantioselective conjugate addition of photogenerated α-amino radicals to Michael acceptors catalyzed by a newly prepared chiral-at-metal rhodium complex. This protocol shows that a single Rh(iii) complex can serve not only as a Lewis acid but also as a photoredox catalyst to control the stereoselectivity during the bond formation.

7.
Oncol Lett ; 12(2): 1197-1203, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27446418

ABSTRACT

Members of the microRNA (miR)-183 family are expressed at high levels in the majority of cancer types, including breast and prostate, and are considered 'oncomiRs'. The purpose of the present study was to investigate the role of exosomes in cell-to-cell transfer of the miR-183 family, which includes miRs-96, -182 and -183. Despite highly detectable levels of these three miRs within prostate and breast cells in vitro, only miR-182 was detectable in exosomes isolated from cell culture supernatant. Similar to the in vitro results, miR-182 was the only miR detected in exosomes isolated from fresh human serum. The packaging of miR-182 into exosomes was examined in MDA-MB-231 (MDA-182) breast cancer cells with miR-182 overexpression. Levels of mature miR-182 increased in exosomes in a dose-dependent manner compared to intracellular expression. Furthermore, co-culture of MDA-182 cells with naïve MDA-MB-231 cells resulted in an increase in mature miR-182 in the naïve cells, which was blocked by a chemical inhibitor of microvesicle formation. In summary, the present study demonstrates that of the miR-183 family members, miR-182 is preferentially packaged in exosomes, detectable in exosomes from human sera and may be transferred between cells via a microvesicle-dependent mechanism.

8.
Reproduction ; 151(6): 643-55, 2016 06.
Article in English | MEDLINE | ID: mdl-27001999

ABSTRACT

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder in women and is characterised by polycystic ovaries, hyperandrogenism and chronic anovulation. Although the clinical and biochemical signs of PCOS are typically heterogeneous, abnormal folliculogenesis is considered a common characteristic of PCOS. Our aim is to identify the altered miRNA and mRNA expression profiles in the cumulus cells of PCOS patients to investigate their molecular function in the aetiology and pathophysiology of PCOS. In this study, the miRNA expression profiles of the cumulus cell samples isolated from five PCOS and five control patients were determined by an miRNA microarray. At the same time, the altered mRNA profiles of the same cumulus cell samples were also identified by a cDNA microarray. From the microarray data, 17 miRNAs and 1263 mRNAs showed significantly different expression in the PCOS cumulus cells. The differentially expressed miRNA-509-3p and its potential target gene (MAP3K8) were identified from the miRNA and mRNA microarrays respectively. The expression of miRNA-509-3p was up-regulated and MAP3K8 was down-regulated in the PCOS cumulus cells. The direct interaction between miRNA-509-3p and MAP3K8 was confirmed by a luciferase activity assay in KGN cells. In addition, miRNA-509-3p mimics or inhibitor transfection tests in KGN cells further confirmed that miRNA-509-3p improved oestradiol (E2) secretion by inhibiting the expression of MAP3K8 These results help to characterise the pathogenesis of anovulation in PCOS, especially the regulation of E2 production.


Subject(s)
Cumulus Cells/metabolism , Estradiol/metabolism , MAP Kinase Kinase Kinases/metabolism , MicroRNAs/genetics , Polycystic Ovary Syndrome/genetics , Proto-Oncogene Proteins/metabolism , RNA, Messenger/genetics , Adult , Case-Control Studies , Cell Communication , Cells, Cultured , Cumulus Cells/pathology , Female , Gene Expression Profiling , Humans , MAP Kinase Kinase Kinases/genetics , Oligonucleotide Array Sequence Analysis , Polycystic Ovary Syndrome/pathology , Proto-Oncogene Proteins/genetics
9.
Zhongguo Zhong Yao Za Zhi ; 41(20): 3746-3752, 2016 Oct.
Article in Chinese | MEDLINE | ID: mdl-28929651

ABSTRACT

Soil and Uncaria rhynchophylla in different functional areas were selected for the study,the content of heavy metals such as As, Cd, Cu, Cr, Pb, and Hg in soil and U. rhynchophylla was discussed, the characteristics of their accumulation in the U.rhynchophylla was analyzed, the contamination levels of heavy metals in soil in different functional areas was evaluated. The results showed that content of Cu, As, Pb and Cr in soil was being cropland>woodland>wasteland, content of Cd was being woodland>cropland>wasteland, content of Hg was being cropland>woodland>wasteland. According to quality standard of soil environment, soil Cd in woodland, cropland and wasteland all exceeded the state-level standards, soil Cd in woodland exceeded the secondary standard, soil Hg in cropland and wasteland all exceeded the state-level standards. According to technical conditions of green food producing area, soil Cd in woodland exceeded the limit value of standard. According to Green Trade Standards of Importing Exporting Medicinal Plants Preparations,the content of heavy metals of U.rhynchophylla in cropland,woodland and wasteland were correspond to the specification. From the single factor pollution index, the soil in woodland was polluted by Cd. From the comprehensive pollution index, the soils in different functional areas were not contaminated by heavy metals. The enrichment coefficient of heavy metals such as As, Cu, Cr, and Pb in hook of U.rhynchophylla was being wasteland>woodland>cropland, the enrichment coefficient of Cu in hook of U. rhynchophylla in wasteland was more than 1. Except Cu, the enrichment coefficient of other heavy metals was low.


Subject(s)
Metals, Heavy/analysis , Soil Pollutants/analysis , Uncaria/growth & development , Cadmium/analysis , Mercury/analysis , Soil/chemistry
10.
Zhong Yao Cai ; 38(3): 531-5, 2015 Mar.
Article in Chinese | MEDLINE | ID: mdl-26495656

ABSTRACT

OBJECTIVE: To establish a method of quantitative analysis of multi-components, by single marker(QAMS)for simultaneously determining six ingredients in Gardenia jasminoides fruits. METHODS: A multi-wavelength segmentation detection method was used. A methodological mode was found to analysis six ingredients in Gardenia jasminoides fruits by quantitative analysis of QAMS. Taken geniposide as reference to create RCF with gardenia acid, chlorogenic acid, crocin I, crocin II and crocin III. RESULTS: The good reproducibility and acceptable durability of method was validated between two HPLC systems and three columns. 20 batches of Gardenia jaminoides fruits was analysis, and the results showed good linear correlation compared to external standard method (r > 0. 999). CONCLUSION: QAMS can be used as quality evaluation method of multi-component Gardenia jaminoides fruits.


Subject(s)
Fruit/chemistry , Gardenia/chemistry , Phytochemicals/chemistry , Carotenoids , Chlorogenic Acid , Chromatography, High Pressure Liquid , Drugs, Chinese Herbal , Iridoids , Phytochemicals/isolation & purification , Reproducibility of Results
11.
J Am Chem Soc ; 137(44): 14039-42, 2015 Nov 11.
Article in English | MEDLINE | ID: mdl-26488384

ABSTRACT

An efficient enantioselective classic three-component Passerini reaction with a broad substrate scope in the presence of a chiral phosphoric acid catalyst has been developed. This represents the general example for classic three-component Passerini reaction with good to excellent enantioselectivies involving aromatic aldehydes and the bulky pivalaldehyde under mild reaction conditions. The feature of this method is highlighted by using a chiral phosphoric acid to activate carboxylic acid, aldehyde, and isocyanide for the facile construction of widely useful complex compounds.

12.
Chem Commun (Camb) ; 50(72): 10491-4, 2014 Sep 18.
Article in English | MEDLINE | ID: mdl-25068593

ABSTRACT

A novel and efficient method for the construction of γ-lactams with an all-carbon quaternary center is developed via a DABCO-catalyzed reaction of EWG-activated cyclopropanecarboxamides and electron-deficient alkenes. The process involves sequential ring-opening of activated cyclopropanes, intermolecular Michael addition and intramolecular aza-cyclization.


Subject(s)
Amides/chemistry , Cyclopropanes/chemistry , Lactams/chemistry , Piperazines/chemistry , Acrylonitrile/chemistry , Aza Compounds/chemistry , Carbon/chemistry , Catalysis , Crystallography, X-Ray , Cyclization , Molecular Conformation
13.
Org Biomol Chem ; 12(33): 6389-92, 2014 Sep 07.
Article in English | MEDLINE | ID: mdl-25008794

ABSTRACT

An efficient synthesis of γ-ketoamides was developed by the one-pot multicomponent reaction of chalcones, malononitrile and DMF (as both the reactant and solvent) in the presence of NaOH (3.0 equiv.). The reaction features high atom economy, easily available starting materials, operational simplicity, and good tolerance with diverse functional groups.


Subject(s)
Amides/chemical synthesis , Chalcones/chemistry , Dimethylformamide/chemistry , Nitriles/chemistry , Amides/chemistry , Models, Molecular , Molecular Structure
14.
Chem Commun (Camb) ; 50(53): 6995-7, 2014 Jul 07.
Article in English | MEDLINE | ID: mdl-24844738

ABSTRACT

Efficient synthesis of spiro[isoquinolinone-4,2'-oxiranes] was achieved based on a multicomponent one-pot reaction of readily available cis-2-acetyl-oxirane-2-carboxamides, arylaldehydes and malononitrile at room temperature. However, in the reaction with trans-2-acetyl-oxirane-2-carboxamide substrates, 3-iminoisoindolinones were obtained in moderate to high yields.

15.
Org Biomol Chem ; 12(8): 1341-50, 2014 Feb 28.
Article in English | MEDLINE | ID: mdl-24435406

ABSTRACT

Hypervalent iodine(III)-mediated dioxygenation and diamination of alkenes have been previously developed. In this study, the potential application of hypervalent iodine(III) reagent was successfully extended to the dialkylation and cyclopropa(e)nation of unsaturated alkenes and alkynes. The reactions of alkenes with malononitrile and other active methylene compounds as the carbon nucleophiles give access to multisubstituted cyclopropane derivatives in moderate to excellent yields. Both electron-rich and electron-deficient alkenes are suitable substrates. Alkynes, no matter terminal or internal alkynes, work well, affording the corresponding highly functionalized cyclopropenes efficiently. A plausible mechanism of iodo(III)cyclopropanation, ring opening attack by the carbon-nucleophile, and recyclization was proposed for the cyclopropanation of trans-alkene substrates. The cyclopropenation was thought to proceed via iodo(III)cyclopropanation, ring-opening attack by the carbon-nucleophile, recyclization into a four-membered iodo(III)cyclobutene and final reductive elimination. The protocol might provide a complementary route to cyclopropanation/cyclopropenation.


Subject(s)
Alkenes/chemistry , Alkynes/chemistry , Cyclopropanes/chemistry , Iodine/chemistry , Catalysis , Nitriles/chemistry
16.
Org Biomol Chem ; 11(41): 7212-7, 2013 Nov 07.
Article in English | MEDLINE | ID: mdl-24056991

ABSTRACT

The reaction of 1-alkenoylcyclopropane carboxylic acids with NBS or NIS was investigated, which provides an efficient route to biologically important 7-halogenated furo[3,2-c]pyran-4-ones in a one-pot transformation. The major pathway for the formation of the O-O heterocycles was proposed as a halo-oxa-cyclization, HBr elimination, cyclopropane ring-opening and recyclization (intramolecular oxa-cyclization), and bromination cascade. The double-oxa-cyclization represents a novel synthetic strategy towards functionalized furo[3,2-c]pyranones.


Subject(s)
Hydrocarbons, Halogenated/chemical synthesis , Oxygen/chemistry , Pyrones/chemistry , Crystallography, X-Ray , Cyclization , Hydrocarbons, Halogenated/chemistry , Models, Molecular , Molecular Structure
17.
Org Lett ; 15(15): 3978-81, 2013 Aug 02.
Article in English | MEDLINE | ID: mdl-23869601

ABSTRACT

A DABCO-mediated organocatalyzed anion relay cascade based on 1-cinnamoylcyclopropanecarboxamides has been developed and applied in the construction of 2,3-dihydrofurans with the original alkene and amide functionalities intact. In the aza-oxy-carbanion relay process, DABCO provides both the electron source and sink. The enolate anion-triggered ring opening of the cyclopropane is ascribed to the key step in the anion relay cascade.


Subject(s)
Anions/chemistry , Cyclopropanes/chemistry , Furans/chemistry , Furans/chemical synthesis , Catalysis , Molecular Structure
18.
Huan Jing Ke Xue ; 34(3): 1055-61, 2013 Mar.
Article in Chinese | MEDLINE | ID: mdl-23745414

ABSTRACT

The objective of this paper is to investigate the concentrations and distribution characteristics of heavy metals in surface sediments of different areas in the Caohai plateau wetland. 16 samples of surface sediments were collected and 7 heavy metals were analyzed. Heavy metal pollution in surface sediments of different areas in the Caohai plateau wetland was estimated by the Tomlinson Pollution Load Index (PLI) method. The analyzed results indicated that the average contents of Cd, Hg, As, Pb, Cr, Cu, Zn were 0.985, 0.345, 15.8, 38.9, 38.6, 22.8 and 384 mg x kg(-1), respectively. The heavy metal distributions varied with regional environment changes, the order of average contents of Cd and Hg in different regions was E (the eastern region) > S (the southern region) > N (the northern region), the order of the average content of Pb was N > E > S, and that of Zn was S > E > N. The results also suggested a medium heavy metal pollution level in the surface sediment of the Caohai plateau wetland with the PLI(zone) reaching 1.17. The order of pollution level in surface sediments of different regions was E > S > N. The results showed medium pollution levels in E and Hg which reached the extreme intensity pollution level were also the major polluted elements in surface sediments of the Caohai plateau wetland. And also, results showed medium pollution levels of Cd and Pb in surface sediments of Caohai plateau wetland. Cluster analysis results showed similar pollution sources of Cd, Zn, Pb and Hg, which should be attached great importance in terms of the prevention of the Caohai plateau wetland.


Subject(s)
Ecosystem , Geologic Sediments/chemistry , Metals, Heavy/analysis , Water Pollutants, Chemical/analysis , Wetlands , Altitude , China , Environmental Monitoring
19.
Org Lett ; 15(4): 852-5, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-23368840

ABSTRACT

A one-pot cascade transformation of chalcones into ß-imidoketones has been developed, in which NBS provides both electrophilic bromine and nucleophilic nitrogen sources, and DBU functions as a nucleophilic reagent to activate NBS to be a more electrophilic bromine species and to further remove the bromine of α-bromoketones. The whole process involves tandem bromoamination and debromination, which represents a unique example of preparing ß-aminoketones by the reaction of chalcones with the NBS/DBU combination.


Subject(s)
Bromosuccinimide/chemistry , Chalcones/chemistry , Hydrocarbons, Brominated/chemistry , Amination , Bridged Bicyclo Compounds, Heterocyclic/chemistry , Catalysis , Molecular Structure , Stereoisomerism
20.
Org Biomol Chem ; 11(15): 2460-5, 2013 Apr 21.
Article in English | MEDLINE | ID: mdl-23429527

ABSTRACT

NBS-mediated addition-elimination reaction of sulfonamides/carboxamides and formamides afforded N-sulfonylamidines and N-formylarylamides, respectively, depending on the different mechanism of elimination. Hydrogen bond-induced proton transfer leads to enhanced reactivities and was proposed as the key driving force for the reaction to take place. The protocol demonstrates the possibility of constructing chemical bonds based on a proton transfer strategy induced by noncovalent hydrogen bond interaction.


Subject(s)
Formamides/chemistry , Protons , Sulfonamides/chemistry , Hydrogen Bonding , Models, Molecular , Molecular Conformation
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