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Hydroxymethylation hydroxylation of 1,3-diarylpropene through a catalytic diastereoselective Prins reaction:cyclization logic and access to brazilin core
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作者 Xin-Ting Hu Qing-Yan Cheng +4 位作者 Yan-Ping Chen Kun Li Cai-Xian Yan Dashan Li Li-Dong Shao 《Natural Products and Bioprospecting》 CSCD 2024年第1期511-526,共16页
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
关键词 Catalytic Prins reaction hydroxymethylation/hydroxylation 1 3-Diarylpropene BRAZILIN
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Oxidation of 2,5‐bis(hydroxymethyl)furan to 2,5‐furandicarboxylic acid catalyzed by carbon nanotube‐supported Pd catalysts 被引量:3
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作者 Zhenyu Li Liyuan Huai +5 位作者 Panpan Hao Xi Zhao Yongzhao Wang Bingsen Zhang Chunlin Chen Jian Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期793-801,共9页
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
关键词 2 5‐Bis(hydroxymethyl)furan 2 5‐Furandicarboxylic acid Palladium hydride 5‐hydroxymethylfurfural Catalytic oxidation
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A selective detection of fluoride ions in DMSO by fluorescent and colorimetry competition assays based on 4-bromo-2,6-bis-(hydroxymethyl)phenol 被引量:3
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作者 Hossein Tavallali Gohar Deilamy-Rad Mahboobe Tabandeh 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第2期193-196,共4页
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
关键词 4-Bromo-2 6-bis(hydroxymethyl)phenol COLORIMETRIC Fluorometric F Chromophoric functions
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Synthesis and Structural Characterization of 2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol 被引量:3
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作者 毕福强 王伯周 +4 位作者 樊学忠 许诚 葛忠学 刘庆 张国防 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第3期415-419,共5页
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
关键词 2 3-bis(hydroxymethyl)-2 3-dinitro-1 4-butanediol SYNTHESIS characterization crystal structure
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5-hydroxymethyl-2-furfural prolongs survival and inhibits oxidative stress in a mouse model of forebrain ischemia 被引量:6
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作者 Bailiu Ya Lan Zhang +2 位作者 Li Zhang Yali Li Lin Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第22期1722-1728,共7页
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
关键词 5-hydroxymethyl-2-furfural forebrain ischemia survival time oxidative stress SUPEROXIDEDISMUTASE MALONDIALDEHYDE MOUSE
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A Practical and Efficient Procedure for Preparation of Diacetals from 2,2-Bis(hydroxymethyl) propane-1,3-diol with Aldehydes and Ketones Catalysed by Anhydrous Ferrous Sulfate 被引量:6
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期285-285,共1页
关键词 A Practical and Efficient Procedure for Preparation of Diacetals from 2 2-Bis hydroxymethyl propane-1 3-diol with Aldehydes and Ketones Catalysed by Anhydrous Ferrous Sulfate
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One-pot synthesis of 2,5-bis(hydroxymethyl)furan from biomass derived 5-(chloromethyl)furfural in high yield 被引量:2
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作者 Binglin Chen Yunchao Feng +9 位作者 Sen Ma Weizhen Xie Guihua Yan Zheng Li Jonathan Sperry Shuliang Yang Xing Tang Yong Sun Lu Lin Xianhai Zeng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期421-428,I0011,共9页
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
关键词 2 5-Bis(hydroxymethyl)furan Hydrolysis Hydrogenation Biomass conversion Heterogeneous catalysis
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Helical Coordination Polymer with a 3-Fold Interpenetration Structure Based on 5-(Hydroxymethyl)isophthalic Acid 被引量:9
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作者 徐中轩 马钰璐 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第7期1193-1198,共6页
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
关键词 5-(hydroxymethyl isophthalic acid helical coordination polymer 3-fold interpenetration structure
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Kaiso mainly locates in the nucleus in vivo and binds to methylated,but not hydroxymethylated DNA 被引量:1
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作者 Sisi Qin Baozhen Zhang +3 位作者 Wei Tian Liankun Gu Zheming Lu Dajun Deng 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2015年第2期148-155,共8页
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
关键词 Kaiso COMPARTMENTALIZATION DNA binding METHYLATION hydroxymethylATION CDKN2A
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Catalyst design strategy toward the efficient heterogeneously-catalyzed selective oxidation of 5-hydroxymethylfurfural 被引量:2
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作者 Huai Liu Xing Tang +5 位作者 Xianhai Zeng Yong Sun Xixian Ke Tianyuan Li Jiaren Zhang Lu Lin 《Green Energy & Environment》 SCIE EI CSCD 2022年第5期900-932,共33页
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
关键词 hydroxymethyl CATALYST CATALYZED
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Effect of Butyl α-Hydroxymethyl Acrylate Monomer Structure on the Morphology Produced via Aqueous Emulsion Polymerization-induced Self-assembly 被引量:2
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作者 Shou-Kuo Man Xiao Wang +1 位作者 Jin-Wen Zheng Ze-Sheng An 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第1期9-16,I0005,共9页
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
关键词 Block copolymer α-hydroxymethyl acrylate RAFT emulsion polymerization Polymerization-induced self-assembly
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Synthesis of bis(amino)furans from biomass based 5-hydroxymethyl furfural 被引量:2
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作者 Xiaoyu Wang Wei Chen +5 位作者 Zheng Li Xianhai Zeng Xing Tang Yong Sun Tingzhou Lei Lu Lin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第1期209-214,共6页
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
关键词 5-hydroxymethyl furfuralN-Acyl-5-aminomethyl furfura2 5-bis(Aminomethyl) furanRitter reactionReductive amination
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5-Hydroxymethylfurfural from wine-processed Fructus corni inhibits hippocampal neuron apoptosis 被引量:1
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作者 Hai Gu Zequn Jiang +5 位作者 Mingyan Wang Haiying Jiang Fengming Zhao Xia Ding Baochang Cai Zhen Zhan 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第28期2605-2614,共10页
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
关键词 neural regeneration traditional Chinese medicine neurodegenerative disease 5-hydroxymethyl-furfural Fructus comi hippocampus neuron oxidative stress APOPTOSIS grants-supported paper NEUROREGENERATION
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A contribution to the study of the modified Marschalk reaction:Hydroxymethylation of 6,8-O-dimethyl emodin
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作者 Hai Shan Jin,Li Ming Zhao School of Chemistry and Chemical Engineering,Xuzhou Normal University,Xuzhou 221116,China 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期568-571,共4页
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
关键词 Marschalk reaction hydroxymethylATION EMODIN Antitumor activity
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STUDIES ON THE TOTAL SYNTHESIS OF(-)-(2R,5S)-2-METHYL-5-HYDROXYMETHYL-δ-VALEROLACTONE
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作者 He Ping ZENG(Department of Chemistry, South China Normal Universitys Guangzhou 510631) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第4期283-284,共2页
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.
关键词 TOTAL SYNTHESIS ON STUDIES OF hydroxymethyl METHYL
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New Method for Reducing 2,6-Pyridinedicarboxylic Acid Diethyl Ester to 2,6-Di(hydroxymethyl)pyridine
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作者 Wu Xinyan He Yongbin +2 位作者 Wu Chengtai Wu Xinyan He Yongbin Wu Chengtai (Department of Chemistry, Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期105-106,共2页
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%.
关键词 REDUCE 2 6-pyridinedicarboxylic acid diethyl ester 2 6-di (hydroxymethyl) pyridine
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A Novel Method for Synthesizing 4,4′-Bis(hydroxymethyl)-2,2′-bipyridine
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作者 SU Zhong min CHEN Li hua +3 位作者 WU Li xin XU Hong bin ZHU Dong xia WANG Rong shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期345-347,共3页
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
关键词 4 4′-Bis(hydroxymethyl)-2 2′-bipyridine Synthesis 4 4-Dimethyl-2 2′-bipyridine
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Synthesis of 2S-Hydroxymethyl-3R, 4R-dihydroxypyrrolidine
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作者 Zhen CHEN Ren Yun WANG +1 位作者 Li Lian ZHU Xiao Tian LIANG (Institute of Materia Medica. Peking Union Medical College) (The Chinese Academy of Medical Sciences, Bejing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第8期651-652,共2页
The sythesis of 2S-hydroxymethyl-3R, 4R-dihydroxypyrrolidine from D-arabinose was described in this paper.
关键词 polydroxylated pyrrolidine 2S-hydroxymethyl-3R 4R-dihydroxypyrrolidine D-arabinose
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Increase of Lignin Reactivity by Means of Depolymerization and Hydroxymethylation for Its Use in Synthetic Wood Elaboration
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作者 Alvaro Jimenez Marco Vega Bibiana Gordillo 《Journal of Chemistry and Chemical Engineering》 2012年第2期124-137,共14页
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
关键词 DEPOLYMERIZATION hydroxymethylATION LIGNIN peat.
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Fibrillation Property of the Lyocell Fibers Treated by W-hydroxymethyl Cross-linking Agents
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作者 房宽峻 郝龙云 +1 位作者 胡学超 邵惠丽 《Journal of Donghua University(English Edition)》 EI CAS 2002年第4期24-28,共5页
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
关键词 N-hydroxymethyl fibrillation LYOCELL fibers
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