A catalytic diastereoselective Prins reaction for hydroxymethylation and hydroxylation of 1,3-diarylpropene was successfully utilized to prepare various 1,3-dioxanes7 in 14-88%yields.Take advantage of the synthetic in...A catalytic diastereoselective Prins reaction for hydroxymethylation and hydroxylation of 1,3-diarylpropene was successfully utilized to prepare various 1,3-dioxanes7 in 14-88%yields.Take advantage of the synthetic intermediate7h,the key B/C rings in brazilin core could be constructed by the sequential of Friedel-Crafts/Ullmann-Ma rather than Ullmann-Ma/Friedel-Crafts reactions.展开更多
The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under...The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under ambient pressure,the modified carbon nanotube‐supported Pd‐based catalysts demonstrate the maximum FDCA yield of 93.0%with a full conversion of BHMF after 60 min at 60°C,much superior to that of the traditional route using 5‐hydroxymethylfurfural(HMF)as substrates(only a yield of 35.7%).The participation of PdH_(x) active species with metallic Pd can be responsible for the encouraging performance.Meanwhile,a possible reaction pathway proceeding through 2,5‐diformylfuran(DFF)and 5‐formyl‐2‐furancarboxylic acid(FFCA)as process intermediates is suggested for BHMF route.The present work may provide new opportunities to synthesize other high value‐added oxygenates by using BHMF as an alternative feedstock.展开更多
A novel and very simple colorimetric and fluorometric method for selectively sensing F^- was proposed based on 4-bromo-2,6- bis(hydroxymethyl)phenol(BBHMP),which is a simple and available phenolic receptor the abs...A novel and very simple colorimetric and fluorometric method for selectively sensing F^- was proposed based on 4-bromo-2,6- bis(hydroxymethyl)phenol(BBHMP),which is a simple and available phenolic receptor the absence of any special chromophoric function and with over wide range of anions(Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-) in DMSO media.The colorimetric method is described for naked-eye detection of F^- in the presence of the BBHMP.The BBHMP was found to show selective and sensitive fluorescence quenching response toward fluoride over than Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-.展开更多
2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol(C6H12N2O8) was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the t...2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol(C6H12N2O8) was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the title compound was characterized by 1H NMR,13C NMR,FT-IR,elementary analysis,and X-ray single-crystal diffraction analysis,which reveals that the title compound crystallizes in triclinic,space group P with a = 0.6324(2),b = 0.6454(3),c = 0.7062(3) nm,α= 111.550(4),β= 95.505(4),γ= 113.395(4)°,V = 0.23595(16) nm3,Z = 1,Mr = 240.18,Dc = 1.690 g·cm-3,μ = 0.159 mm-1,F(000) = 126,R = 0.0304 and wR = 0.0907.展开更多
In the present study, we hypothesized that 5-hydroxymethyl-2-furfural could attenuate ischemic brain damage by reducing oxidative injury. Thus, mice were subjected to bilateral common carotid artery occlusion to estab...In the present study, we hypothesized that 5-hydroxymethyl-2-furfural could attenuate ischemic brain damage by reducing oxidative injury. Thus, mice were subjected to bilateral common carotid artery occlusion to establish a model of permanent forebrain ischemia. The mice were intraperitoneally injected with 5-hydroxymethyl-2-furfura130 minutes before ischemia or 5 minutes after ischemia. The survival time of mice injected with 5-hydroxymethyl-2-furfural was longer compared with untreated mice. The mice subjected to ischemia for 30 minutes and reperfusion for 5 minutes were intraperitoneally injected with 5-hydroxymethyl-2-furfural 5 minutes prior to reperfusion, which increased superoxide dismutase content and reduced malondialdehyde content, similar to the effects of Edaravone, a hydroxyl radical scavenger used for the treatment of stroke. These findings indicate that intraperitoneal injection of 5-hydroxymethyl-2-furfural can prolong the survival of mice with permanent forebrain ischemia. This outcome may be mediated by its antioxidative effects.展开更多
5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated...5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated for the first time.A 91%BHMF yield was obtained over Ru/Cu Oxcatalyst,and BHMF was mainly produced by the consecutive hydrolysis and hydrogenation of CMF with 5-hydroxymethylfurfural(HMF)as an intermediate.Kinetic studies revealed that the conversion of HMF to BHMF was the rate-determining step.Remarkably,the characterizations and density functional theory(DFT)calculations further revealed the lower electron density of Ru NPs in Ru/Cu Oxcatalyst,resulting in a larger adsorption energy and a smaller free energy difference for the formation of alcohols.The present findings offered a new pathway for biomass-derived diol production through CMF as a potential source.展开更多
5-(Hydroxymethyl) isophthalic acid (H2HIA) as a novel organic ligand was prepared from 3,5-bis(methoxycarbonyl)benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold inter...5-(Hydroxymethyl) isophthalic acid (H2HIA) as a novel organic ligand was prepared from 3,5-bis(methoxycarbonyl)benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold interpenetration structure, namely [Zn1/2(HIA)1/2(DPEE)1/2]n (1), was hydrothermally synthesized at 160 ℃, using H2HIA ligands to assemble with DPEE ligands and Zn2+ ions. Complex 1 crystalizes in orthorhombic system, space group Pnna, with a = 8.2118(5), b = 17.1698(7), c =14.9922(7) ?, V = 2113.82(18) ?3, μ = 1.194 mm-1, Z = 4 and S = 0.967. Moreover, some physical characteristics of complex 1, such as powder X-ray diffraction (PXRD), thermogravimetry analyses (TGA) and photoluminescent properties, were also investigated.展开更多
Objective: Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization i...Objective: Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods: Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein (EGFP) tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation assay (CHIP). Results: Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions: Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences.展开更多
The selective oxidation of 5-hydroxymethylfurfural(HMF),a versatile bio-based platform molecule,leads to the formation of several intriguing and useful downstream chemicals,such as 2,5-diformylfuran(DFF),5-hydroxymeth...The selective oxidation of 5-hydroxymethylfurfural(HMF),a versatile bio-based platform molecule,leads to the formation of several intriguing and useful downstream chemicals,such as 2,5-diformylfuran(DFF),5-hydroxymethyl-2-furancarboxylic acid(HMFCA),formyl 2-furancarboxylic acid(FFCA),2,5-furandicarboxylic acid(FDCA) and furan-2,5-dimethylcarboxylate(FDMC).These products have been extensively employed to fabricate novel polymers,pharmaceuticals,sustainable dyes and many other value-added fine chemicals.The heart of the developed HMF oxidation processes is always the catalyst.In this regard,this review comprehensively summarized the established heterogeneous catalyst design strategy for the selective oxidation of HMF via thermo-catalysis.Particular attention has been focused on the reaction mechanism of HMF oxidation over different catalysts as well as enhancing the catalytic performance of the catalyst through manipulating the properties of the support and fabricating of multi-component metal nano-particles and oxides.The current challenges and possible research directions for the catalytic oxidation of HMF in the future are also discussed.展开更多
Polymerization-induced self-assembly(PISA) is an efficient and versatile method to afford polymeric nano-objects with polymorphic morphologies. Compared to dispersion PISA syntheses based on soluble monomers, the vast...Polymerization-induced self-assembly(PISA) is an efficient and versatile method to afford polymeric nano-objects with polymorphic morphologies. Compared to dispersion PISA syntheses based on soluble monomers, the vast majority of emulsion PISA formulations using insoluble monomers leads to kinetically-trapped spheres. Herein, we present aqueous emulsion PISA formulations generating worms and vesicles besides spheres. Two monomers with different butyl groups, n-butyl(n BHMA) and tert-butyl(t BHMA) α-hydroxymethyl acrylate, and thus possessing different water solubilities were synthesized via Baylis-Hillman reaction. Photoinitiated aqueous emulsion polymerizations of n BHMA and t BHMA employing poly(ethylene glycol) macromolecular chain transfer agents(macro-CTAs, PEG45-CTA, and PEG113-CTA) at 40 °C were systematically investigated to evaluate the effect of monomer structure and solubility on the morphology of the generated block copolymer nano-objects. Higher order morphologies including worms and vesicles were readily accessed for t BHMA, which has a higher water solubility than that of n BHMA. This study proves that plasticization of the core-forming block by water plays a key role in enhancing chain mobility required for morphological transition in emulsion PISA.展开更多
In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct r...In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct reductive amination of aldehyde group. For the Ritter reaction of 5-hydroxymethyl furfural, mixture of trifluoromethane sulfonic acid and phosphoric anhydride showed good performance and the intermediate N-acyl-5-aminomethyl furfural with the highest yield of 89.1 wt% was obtained.Optimization of direct reductive amination of 2,5-bis(aminomethyl) furan was conducted and a yield of45.7 wt% was achieved. This study presents a simple way for preparing bis(amino)furans from renewable biomass based 5-hydroxymethyl furfural, which enriches the biorefinery concept from biomass.展开更多
Previous studies have shown that 5-hydroxymethylfurfural, a compound extracted from wine- processed Fructus corni, has a protective effect on hippocampal neurons. The present study was designed to explore the related ...Previous studies have shown that 5-hydroxymethylfurfural, a compound extracted from wine- processed Fructus corni, has a protective effect on hippocampal neurons. The present study was designed to explore the related mechanisms. Our study revealed that high and medium doses (10, 1 μmol/L) of 5-hydroxymethylfurfural could improve the morphology of H2O2-treated rat hippocampal neurons as revealed by inverted phase-contrast microscopy and transmission electron microscopy. MTT results showed that incubation with high and medium doses of 5-hydroxymethylfurfural caused a significant increase in the viability of neuronal cells injured by H2O2. Flow cytometry assays con- firmed that H2O2 could induce cell apoptosis, while high and medium doses of 5-hydroxymethylfurfural had a visible protective effect on apoptotic rat hippocampal neurons. Real-time PCR and western blot analysis showed that high and medium doses of 5-hydroxymethylfurfural prevented H2O2-induced up-regulation of p53, Bax and caspase-3 and an- tagonized the down-regulation of Bcl-2 induced by H2O2 treatment. These results suggested that 5-hydroxymethylfurfural could inhibit apoptosis of cultured rat hippocampal neurons injured by H2O2 via increase in Bcl-2 levels and decrease in p53, Bax and caspase-3 protein expression levels.展开更多
Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk reaction.The influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was discusse...Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk reaction.The influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was discussed.The results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.展开更多
The total synthesis of Al9a antibiotic, was carried out by a method involving alkylation of 2-ethoxy-cargony 1-eyclopentanone under the chiral phasa. transfer catalyst condition in the key step.
Reducing 2, 6-pyridinedicaboxylic acid diethyl ester to 2,6-di(hydroxymethyl)pyridine was carried out by using NaBH4/CaCl2 as reducing agent. It is an improved and efficient method. The yield is up to 91%.
There are several paths for synthesizing 4,4′ bis(hydroxymethyl) 2,2′ bipyridine, but most of them need strict experimental conditions that are not easy to be overcome. We designed a simple way to prepare this produ...There are several paths for synthesizing 4,4′ bis(hydroxymethyl) 2,2′ bipyridine, but most of them need strict experimental conditions that are not easy to be overcome. We designed a simple way to prepare this product via the oxidation of 4,4′ bismethyl 2,2′ bipyridine, followed by esterification and reduction. The yield increases and the reaction conditions become genial in contrast to those of other methods. The molecular structure of the final product was confirmed by means of elemental analysis, IR, 1H NMR and MS spectra.展开更多
Lignin was extracted from peat by Sosa Method. In order to increase its chemical activity, it is necessary to make a structural modification by hydroxymethylation so it can be used in preparation of synthetic wood. De...Lignin was extracted from peat by Sosa Method. In order to increase its chemical activity, it is necessary to make a structural modification by hydroxymethylation so it can be used in preparation of synthetic wood. Depolymerization was made by two methods: (1) reaction oflignin with NaOH 2%; (2) exposition oflignin to UV beam for 6, 12, 24, 36, 48 and 60 hours. The best depolimerization result was with exposition of lignin to UV by 12 hours since phenylpropanoic structure with higher number of free positions (unoccupied carbons) in C3 and C5 of its aromatic ring was obtained. It is known by Mannich Reaction and determination of phenolic OH by UV analysis. Later, its reactivity was increased by hydroxymethylation process by means of reaction of depolymerizated product with formaldehyde and later with glyoxal since it is less toxic. The modified product was mixed with six different kinds of resins (phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, Glyoxal-formaldehyde, urea-formaldehyde and melamine-formaldehyde) to obtain a better mechanical characteristic as a synthetic wood. The best result was the one with melamine-formaldehyde. Finally, this product was mixed with testa rice so final product showed a great hardness and a shinny and smooth appearance.展开更多
Lyocell fibers are subject to fibrillate under wet conditions, which severely affects the appearance of this kind of fabrics. Cross-Unking treatment is an important way to prevent fibrillation of lyocell fibers. In th...Lyocell fibers are subject to fibrillate under wet conditions, which severely affects the appearance of this kind of fabrics. Cross-Unking treatment is an important way to prevent fibrillation of lyocell fibers. In this study, two kinds of traditional N-hydroxymethyl cross-linking agents were used to treat lyocell fibers and the wet abrasion values of lyocell fibers were measured in a wet abrasion test. The results show the wet abrasion values of lyocell fibers increase with the increasing concentration of the cross-linking agents, which indicates the anti-fibrillation property of the treated fibers has been improved. But the mechanical properties of the treated fibers decreased in some extent. The FT-IR spectroscopy analysis shows that the lyocell fibers have cross-linked with cross-linking agents. The SEM analysis results show the fibers treated by 4% DMDHEU or 5% SECO have good anti-fibrillation properties.展开更多
基金support from National Natural Science Foundation of China(82260683 and 22267024)Scientific and Technological Project of Yunnan Precious Metals Laboratory(YPML-2023050265 and YPML-2023050217)+3 种基金Yunnan Science and Technology Talent and Platform Program(202105AG070012)the Top Young Talent of Ten Thousand Talents Program of Yunnan Province(D.L.and L.-D.S.)the Start-up Fund of Yunnan University of Chinese Medicine(2019YZG03)the Bioactive Ethnopharmacol Molecules Chemical Conversion and Application Innovation Team of Department of Education of Yunnan Province(2022).
文摘A catalytic diastereoselective Prins reaction for hydroxymethylation and hydroxylation of 1,3-diarylpropene was successfully utilized to prepare various 1,3-dioxanes7 in 14-88%yields.Take advantage of the synthetic intermediate7h,the key B/C rings in brazilin core could be constructed by the sequential of Friedel-Crafts/Ullmann-Ma rather than Ullmann-Ma/Friedel-Crafts reactions.
文摘The selective oxidation of 2,5‐bis(hydroxymethyl)furan(BHMF)in this work was proven as a promising route to produce 2,5‐furandicarboxylic acid(FDCA),an emerging bio‐based building‐block with wide application.Under ambient pressure,the modified carbon nanotube‐supported Pd‐based catalysts demonstrate the maximum FDCA yield of 93.0%with a full conversion of BHMF after 60 min at 60°C,much superior to that of the traditional route using 5‐hydroxymethylfurfural(HMF)as substrates(only a yield of 35.7%).The participation of PdH_(x) active species with metallic Pd can be responsible for the encouraging performance.Meanwhile,a possible reaction pathway proceeding through 2,5‐diformylfuran(DFF)and 5‐formyl‐2‐furancarboxylic acid(FFCA)as process intermediates is suggested for BHMF route.The present work may provide new opportunities to synthesize other high value‐added oxygenates by using BHMF as an alternative feedstock.
文摘A novel and very simple colorimetric and fluorometric method for selectively sensing F^- was proposed based on 4-bromo-2,6- bis(hydroxymethyl)phenol(BBHMP),which is a simple and available phenolic receptor the absence of any special chromophoric function and with over wide range of anions(Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-) in DMSO media.The colorimetric method is described for naked-eye detection of F^- in the presence of the BBHMP.The BBHMP was found to show selective and sensitive fluorescence quenching response toward fluoride over than Cl^-,Br^-,I^-,AcO^-,HSO4^-,NO3^- and BzO^-.
基金Supported by the National "973" project (No. 613740102)
文摘2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol(C6H12N2O8) was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the title compound was characterized by 1H NMR,13C NMR,FT-IR,elementary analysis,and X-ray single-crystal diffraction analysis,which reveals that the title compound crystallizes in triclinic,space group P with a = 0.6324(2),b = 0.6454(3),c = 0.7062(3) nm,α= 111.550(4),β= 95.505(4),γ= 113.395(4)°,V = 0.23595(16) nm3,Z = 1,Mr = 240.18,Dc = 1.690 g·cm-3,μ = 0.159 mm-1,F(000) = 126,R = 0.0304 and wR = 0.0907.
基金supported by the National Basic Research Program of China (973 Program),No.2003CB517104the National Natural Science Foundation of China,No.30973513+3 种基金Beijing Municipal Science and Technology Program,No.D0206001043191the Natural Science Foundation of Beijing,No.7112061Beijing Key Foundation of Traditional Chinese Medicine,No.KJTS2011-04Beijing Health and Technical Personal of High-Level Plan,No.2009-3-66
文摘In the present study, we hypothesized that 5-hydroxymethyl-2-furfural could attenuate ischemic brain damage by reducing oxidative injury. Thus, mice were subjected to bilateral common carotid artery occlusion to establish a model of permanent forebrain ischemia. The mice were intraperitoneally injected with 5-hydroxymethyl-2-furfura130 minutes before ischemia or 5 minutes after ischemia. The survival time of mice injected with 5-hydroxymethyl-2-furfural was longer compared with untreated mice. The mice subjected to ischemia for 30 minutes and reperfusion for 5 minutes were intraperitoneally injected with 5-hydroxymethyl-2-furfural 5 minutes prior to reperfusion, which increased superoxide dismutase content and reduced malondialdehyde content, similar to the effects of Edaravone, a hydroxyl radical scavenger used for the treatment of stroke. These findings indicate that intraperitoneal injection of 5-hydroxymethyl-2-furfural can prolong the survival of mice with permanent forebrain ischemia. This outcome may be mediated by its antioxidative effects.
基金financially supported by the National Key R&D Program of China 2021YFC2101604)the National Natural Science Foundation of China(22278339,21978248)+1 种基金the Guangdong Provincial Key Research and Development Program(2020B0101070001)the Natural Science Foundation of Fujian Province of China(2019J06005)。
文摘5-(Chloromethyl)furfural(CMF),as a new platform molecular,has become a hot topic in the field of biorefinery.Herein,the one-pot conversion of CMF to 2,5-bis(hydroxymethyl)furan(BHMF)in the water phase was demonstrated for the first time.A 91%BHMF yield was obtained over Ru/Cu Oxcatalyst,and BHMF was mainly produced by the consecutive hydrolysis and hydrogenation of CMF with 5-hydroxymethylfurfural(HMF)as an intermediate.Kinetic studies revealed that the conversion of HMF to BHMF was the rate-determining step.Remarkably,the characterizations and density functional theory(DFT)calculations further revealed the lower electron density of Ru NPs in Ru/Cu Oxcatalyst,resulting in a larger adsorption energy and a smaller free energy difference for the formation of alcohols.The present findings offered a new pathway for biomass-derived diol production through CMF as a potential source.
基金supported by the Natural Science Foundation of Guizhou Province(20122344)125 program of Guizhou Education Department(2012015)the Doctoral Scientific Fund of Zunyi Normal College(2012BSJJ12)
文摘5-(Hydroxymethyl) isophthalic acid (H2HIA) as a novel organic ligand was prepared from 3,5-bis(methoxycarbonyl)benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold interpenetration structure, namely [Zn1/2(HIA)1/2(DPEE)1/2]n (1), was hydrothermally synthesized at 160 ℃, using H2HIA ligands to assemble with DPEE ligands and Zn2+ ions. Complex 1 crystalizes in orthorhombic system, space group Pnna, with a = 8.2118(5), b = 17.1698(7), c =14.9922(7) ?, V = 2113.82(18) ?3, μ = 1.194 mm-1, Z = 4 and S = 0.967. Moreover, some physical characteristics of complex 1, such as powder X-ray diffraction (PXRD), thermogravimetry analyses (TGA) and photoluminescent properties, were also investigated.
基金supported by National Basic Research Program of China(Grant No.2011CB504201)
文摘Objective: Kaiso is upregulated in many cancers and proposed to bind with both methylated- and unmethylated-DNA in the nucleus as a transcriptional repressor. The objective is to define its subcellnlar localization in vivo and exact binding DNA sequences in cells. Methods: Compartmentalization of exogenous Kaiso in cells was tracked with enhanced green fluorescence protein (EGFP) tag. The endogenous Kaiso expression in gastric carcinoma tissue was examined with immunohistochemical staining. Kaiso-DNA binding was tested using electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation assay (CHIP). Results: Kaiso mainly localized in the nucleus of cancer and stromal cells in vivo, but remained in the cytoplasm of cultured cells. Most importantly, nuclear Kaiso can bind with the methylated-CGCG- containing sequence in the CDKN2A promoter, but not with the hydroxymethylated-CGCG sequence in HCT116 cells. Conclusions: Kaiso locates mainly in the nucleus in vivo where it binds with the methylated-CGCG sequences, but does not bind with the hydroxymethylated-CGCG sequences.
基金funding supported by the National Natural Science Foundation of China (Grant Nos. 2207827521978246)+3 种基金the National Key Research and Development Program of China (Grant No. 2019YFB1503903)the Key Area Research and Development Program of Guangdong Province (Grant No. 2020B0101070001)the Fundamental Research Funds for the Central Universities (Grant No. 20720190014)PetroChina Innovation Foundation (2019D5007-0413)。
文摘The selective oxidation of 5-hydroxymethylfurfural(HMF),a versatile bio-based platform molecule,leads to the formation of several intriguing and useful downstream chemicals,such as 2,5-diformylfuran(DFF),5-hydroxymethyl-2-furancarboxylic acid(HMFCA),formyl 2-furancarboxylic acid(FFCA),2,5-furandicarboxylic acid(FDCA) and furan-2,5-dimethylcarboxylate(FDMC).These products have been extensively employed to fabricate novel polymers,pharmaceuticals,sustainable dyes and many other value-added fine chemicals.The heart of the developed HMF oxidation processes is always the catalyst.In this regard,this review comprehensively summarized the established heterogeneous catalyst design strategy for the selective oxidation of HMF via thermo-catalysis.Particular attention has been focused on the reaction mechanism of HMF oxidation over different catalysts as well as enhancing the catalytic performance of the catalyst through manipulating the properties of the support and fabricating of multi-component metal nano-particles and oxides.The current challenges and possible research directions for the catalytic oxidation of HMF in the future are also discussed.
基金financially supported by the National Natural Science Foundation of China (No. 21674059)
文摘Polymerization-induced self-assembly(PISA) is an efficient and versatile method to afford polymeric nano-objects with polymorphic morphologies. Compared to dispersion PISA syntheses based on soluble monomers, the vast majority of emulsion PISA formulations using insoluble monomers leads to kinetically-trapped spheres. Herein, we present aqueous emulsion PISA formulations generating worms and vesicles besides spheres. Two monomers with different butyl groups, n-butyl(n BHMA) and tert-butyl(t BHMA) α-hydroxymethyl acrylate, and thus possessing different water solubilities were synthesized via Baylis-Hillman reaction. Photoinitiated aqueous emulsion polymerizations of n BHMA and t BHMA employing poly(ethylene glycol) macromolecular chain transfer agents(macro-CTAs, PEG45-CTA, and PEG113-CTA) at 40 °C were systematically investigated to evaluate the effect of monomer structure and solubility on the morphology of the generated block copolymer nano-objects. Higher order morphologies including worms and vesicles were readily accessed for t BHMA, which has a higher water solubility than that of n BHMA. This study proves that plasticization of the core-forming block by water plays a key role in enhancing chain mobility required for morphological transition in emulsion PISA.
基金the financial support from the National Natural Science Foundation of China(no.21676223 and no.21506177)the Fujian Provincial Development and Reform Commission,China(no.2015489)+1 种基金the Natural Science Foundation of Fujian Province of China(no.2016J01077 and no.2015J05034)the Fundamental Research Funds for the Central Universities of China(nos.20720160077 and 20720160087)
文摘In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct reductive amination of aldehyde group. For the Ritter reaction of 5-hydroxymethyl furfural, mixture of trifluoromethane sulfonic acid and phosphoric anhydride showed good performance and the intermediate N-acyl-5-aminomethyl furfural with the highest yield of 89.1 wt% was obtained.Optimization of direct reductive amination of 2,5-bis(aminomethyl) furan was conducted and a yield of45.7 wt% was achieved. This study presents a simple way for preparing bis(amino)furans from renewable biomass based 5-hydroxymethyl furfural, which enriches the biorefinery concept from biomass.
基金financially supported by the National Natural Science Foundation of China,No.30772851a grant from the Six Talents Peaks Program of Jiangsu Province,Chinaa grant from the Priority Academic Program Development of Jiangsu Higher Education Institutions,PAPD(Traditional Chinese medicine combined with Western Medicine
文摘Previous studies have shown that 5-hydroxymethylfurfural, a compound extracted from wine- processed Fructus corni, has a protective effect on hippocampal neurons. The present study was designed to explore the related mechanisms. Our study revealed that high and medium doses (10, 1 μmol/L) of 5-hydroxymethylfurfural could improve the morphology of H2O2-treated rat hippocampal neurons as revealed by inverted phase-contrast microscopy and transmission electron microscopy. MTT results showed that incubation with high and medium doses of 5-hydroxymethylfurfural caused a significant increase in the viability of neuronal cells injured by H2O2. Flow cytometry assays con- firmed that H2O2 could induce cell apoptosis, while high and medium doses of 5-hydroxymethylfurfural had a visible protective effect on apoptotic rat hippocampal neurons. Real-time PCR and western blot analysis showed that high and medium doses of 5-hydroxymethylfurfural prevented H2O2-induced up-regulation of p53, Bax and caspase-3 and an- tagonized the down-regulation of Bcl-2 induced by H2O2 treatment. These results suggested that 5-hydroxymethylfurfural could inhibit apoptosis of cultured rat hippocampal neurons injured by H2O2 via increase in Bcl-2 levels and decrease in p53, Bax and caspase-3 protein expression levels.
基金supported by Natural Science Foundation of Xuzhou Normal University(No.08XLB08)Science and Technology Project of Xuzhou(No.XJ09078)Universities Natural Science Foundation of Jiangsu Province (No.09KJD 150006)
文摘Hydroxymethylation of 6,8-O-dimethyl emodin was easily achieved in good yields by the modified Marschalk reaction.The influence of the amount of solvent,base and formaldehyde toward the hydroxymethylation was discussed.The results showed that a relatively dilute reaction solution facilitated the generation of the desired 2-hydromethyl product,while the thick reaction solution benefited the generation of the methylated quinizarins.
文摘The total synthesis of Al9a antibiotic, was carried out by a method involving alkylation of 2-ethoxy-cargony 1-eyclopentanone under the chiral phasa. transfer catalyst condition in the key step.
文摘Reducing 2, 6-pyridinedicaboxylic acid diethyl ester to 2,6-di(hydroxymethyl)pyridine was carried out by using NaBH4/CaCl2 as reducing agent. It is an improved and efficient method. The yield is up to 91%.
基金Supported by the National Natural Science Foundation of China(No. 2 0 16 2 0 0 5 ) the Foundation of EducationMinistry(No. 2 0 0 1- 3) .
文摘There are several paths for synthesizing 4,4′ bis(hydroxymethyl) 2,2′ bipyridine, but most of them need strict experimental conditions that are not easy to be overcome. We designed a simple way to prepare this product via the oxidation of 4,4′ bismethyl 2,2′ bipyridine, followed by esterification and reduction. The yield increases and the reaction conditions become genial in contrast to those of other methods. The molecular structure of the final product was confirmed by means of elemental analysis, IR, 1H NMR and MS spectra.
文摘Lignin was extracted from peat by Sosa Method. In order to increase its chemical activity, it is necessary to make a structural modification by hydroxymethylation so it can be used in preparation of synthetic wood. Depolymerization was made by two methods: (1) reaction oflignin with NaOH 2%; (2) exposition oflignin to UV beam for 6, 12, 24, 36, 48 and 60 hours. The best depolimerization result was with exposition of lignin to UV by 12 hours since phenylpropanoic structure with higher number of free positions (unoccupied carbons) in C3 and C5 of its aromatic ring was obtained. It is known by Mannich Reaction and determination of phenolic OH by UV analysis. Later, its reactivity was increased by hydroxymethylation process by means of reaction of depolymerizated product with formaldehyde and later with glyoxal since it is less toxic. The modified product was mixed with six different kinds of resins (phenol-formaldehyde, urea-formaldehyde, melamine-formaldehyde, Glyoxal-formaldehyde, urea-formaldehyde and melamine-formaldehyde) to obtain a better mechanical characteristic as a synthetic wood. The best result was the one with melamine-formaldehyde. Finally, this product was mixed with testa rice so final product showed a great hardness and a shinny and smooth appearance.
文摘Lyocell fibers are subject to fibrillate under wet conditions, which severely affects the appearance of this kind of fabrics. Cross-Unking treatment is an important way to prevent fibrillation of lyocell fibers. In this study, two kinds of traditional N-hydroxymethyl cross-linking agents were used to treat lyocell fibers and the wet abrasion values of lyocell fibers were measured in a wet abrasion test. The results show the wet abrasion values of lyocell fibers increase with the increasing concentration of the cross-linking agents, which indicates the anti-fibrillation property of the treated fibers has been improved. But the mechanical properties of the treated fibers decreased in some extent. The FT-IR spectroscopy analysis shows that the lyocell fibers have cross-linked with cross-linking agents. The SEM analysis results show the fibers treated by 4% DMDHEU or 5% SECO have good anti-fibrillation properties.