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Protective effect of long-chain polyunsaturated fatty acids on hepatorenal syndrome in rats
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作者 João Bruno Beretta Duailibe Cassiana Macagnan Viau +2 位作者 Jenifer Saffi Sabrina Alves Fernandes Marilene Porawski 《World Journal of Nephrology》 2024年第3期49-61,共13页
BACKGROUND Hepatorenal syndrome(HRS)is the most prevalent form of acute kidney injury in cirrhotic patients.It is characterized by reduced renal blood flow and represents the most severe complication in cirrhotic pati... BACKGROUND Hepatorenal syndrome(HRS)is the most prevalent form of acute kidney injury in cirrhotic patients.It is characterized by reduced renal blood flow and represents the most severe complication in cirrhotic patients with advanced disease.Previous research has indicated that antioxidants can delay the onset of a hyperdynamic circulatory state in cirrhosis and improve renal function in HRS patients.Regular omega-3 supplementation has significantly reduced the risk of liver disease.This supplementation could represent an additional therapy for individuals with HRS.AIM To evaluated the antioxidant effect of omega-3 polyunsaturated fatty acid supplementation on the kidneys of cirrhotic rats.METHODS Secondary biliary cirrhosis was induced in rats by biliary duct ligation(BDL)for 28 d.We used 24 male Wistar rats divided into the following groups:I(control);II(treated with omega-3,1 g/kg of body weight);III(BDL treated with omega-3,1 g/kg of body weight);and IV(BDL without treatment).The animals were killed by overdose of anesthetic;the kidneys were dissected,removed,frozen in liquid nitrogen,and stored in a freezer at-80℃for later analysis.We evaluated oxidative stress,nitric oxide(NO)metabolites,DNA damage by the comet assay,cell viability test,and apoptosis in the kidneys.Data were analyzed by one-way analysis of variance,and means were compared using the Tukey test,with P≤0.05.RESULTS Omega-3 significantly decreased the production of reactive oxygen species(P<0.001)and lipoperoxidation in the kidneys of cirrhotic rats treated with omega-3(P<0.001).The activity of the antioxidant enzymes superoxide dismutase and catalase increased in the BDL+omega-3 group compared to the BDL group(P<0.01).NO production,DNA damage,and caspase-9 cleavage decreased significantly in the omega-3-treated BDL group.There was an increase in mitochondrial electrochemical potential(P<0.001)in BDL treated with omega-3 compared to BDL.No changes in the cell survival index in HRS with omega-3 compared to the control group(P>0.05)were observed.CONCLUSION The study demonstrates that omega-3 can protect cellular integrity and function by increasing antioxidant enzymes,inhibiting the formation of free radicals,and reducing apoptosis. 展开更多
关键词 long-chain polyunsaturated fatty acids Antioxidant effect Hepatorenal syndrome Liver cirrhosis Reactive oxygen species APOPTOSIS
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Preparation for Supramolecular Complexes of Chiral Diols BDPDD, DMBDPD and BINOL with Some Prochiral Compounds
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作者 De Jun LIU Zi Xing SHAN +1 位作者 Rong WANG Jin Gui QIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第4期375-378,共4页
Interaction between chiral diols BDPDD, DMBDPD and BINOL with prochiral compounds was examined and some new supramolecular complexes were prepared. It was found that these chiral hosts could include prochiral guests,... Interaction between chiral diols BDPDD, DMBDPD and BINOL with prochiral compounds was examined and some new supramolecular complexes were prepared. It was found that these chiral hosts could include prochiral guests, a, b-unsaturated compounds or piper- azinedione derivatives to give inclusion crystals in different molar ratio. Formations of these supramolecular complexes were characterized by the data of IR and 1H NMR spectra. 展开更多
关键词 Chiral diols prochical compounds supramolecular complexes preparation.
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Elimination Reaction of α,ω-Diols by Magnesium
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作者 Ji Mao LIN Hui ZHANG +1 位作者 Ai You HAO Qin Zheng YANG(Department of Chemistry, Shandong University, Jinan, 250100) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第8期697-698,共2页
1,3-Propanediol, 1,4-butanediol or 1,5-pentanediol reacts with magnesium to form corresponding magnesium alkoxides, which elindnate water with the formation of cyclic ethers and, respectively, allyl alcohol, 3-buten-1... 1,3-Propanediol, 1,4-butanediol or 1,5-pentanediol reacts with magnesium to form corresponding magnesium alkoxides, which elindnate water with the formation of cyclic ethers and, respectively, allyl alcohol, 3-buten-1-ol and 4-penten-1-ol. 展开更多
关键词 ELIMINATION diols MAGNESIUM
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Synthesis and characterization of new polyesters based on 2,5-bis[(4-chloro carboxyanilino)carbonyl]pyridine and aromatic diols
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作者 Khalil Faghihi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第1期13-17,共5页
Six new polyesters 7a-f were synthesized through the solution polycondensation reaction of diacid chloride 5 with six aromatic diols 6a-f in N,N-dimethyl acetamide(DMAc) as solvent in the presence of pyridine as base.... Six new polyesters 7a-f were synthesized through the solution polycondensation reaction of diacid chloride 5 with six aromatic diols 6a-f in N,N-dimethyl acetamide(DMAc) as solvent in the presence of pyridine as base.The polycondensation reaction produced a series of novel polyester containing pyridyl moiety in the main chain in high yields with inherent viscosities between 0.35 and 0.54 dL/g.The resulted polymers were fully characterized by means of FT-IR spectroscopy,elemental analyses,inherent viscosity ... 展开更多
关键词 High-performance polymers Polyesters Pyridyl moiety Aromatic diols
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Selective monotetrahydropyranylation of symmetrical diols using P_20_5/Si0_2 under solvent-free conditions and their depyranylation
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作者 Hossein Eshghi Mohammad Rahimizadeh Sattar Saberi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1063-1067,共5页
Selective protection of one of the hydroxyl group in 1, n-symmetrical diols is achieved by P2O5/SiO2-catalyzed reaction of the diol with dihydropyran under solvent-free conditions at room temperature. This selective p... Selective protection of one of the hydroxyl group in 1, n-symmetrical diols is achieved by P2O5/SiO2-catalyzed reaction of the diol with dihydropyran under solvent-free conditions at room temperature. This selective protection is simple and it occurred under economically cheap conditions in high yield. The deprotected diol is simply obtained by refluxing of this compound in methanol using the same catalyst without any byproduct formation or additional purifications. 展开更多
关键词 Heterogeneous catalyst P2O5/SiO2 Monotetrahydropyranylation Protecting group Symmetrical diols
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Characterization of four diol dehydrogenases for enantioselective synthesis of chiral vicinal diols
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作者 Jiandong Zhang Rui Dong +5 位作者 Xiaoxiao Yang Lili Gao Chaofeng Zhang Fan Ren Jing Li Honghong Chang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第7期145-154,共10页
Enantiopure vicinal diols are important building blocks used in the synthesis of fine chemicals and pharmaceutical compounds. Diol dehydrogenase(DDH) mediated stereoselective oxidation of racemic vicinal is an efficie... Enantiopure vicinal diols are important building blocks used in the synthesis of fine chemicals and pharmaceutical compounds. Diol dehydrogenase(DDH) mediated stereoselective oxidation of racemic vicinal is an efficient way to prepare enantiopure vicinal diols. In this study, four new bacterial DDHs(AnDDH from Anoxybacillus sp. P3 H1 B, HcDDH from Hazenella coriacea, GzDDH from Geobacillus zalihae and LwDDH from Leptotrichia wadei) were mined from the GenBank database and expressed in E. coli T7.The four DDHs were purified and biochemically characterized for oxidation activity toward(R)-1-phenyl-1,2-ethanediol, with the optimal reaction condition of pH9.0(AnDDH), 10.0(HcDDH) and 11.0(GzDDH and LwDDH) and the temperatures at 40 ℃(AnDDH), 50 ℃(HcDDH) and 60 ℃(GzDDH and LwDDH), respectively. The four enzymes were stable at the pH from 7.0 to 9.0 and below 40 ℃.Kinetic parameters of four DDHs showed that the HcDDH from Hazenella coriacea had high activity toward a broad range of vicinal diols. A series of racemic vicinal diols were successfully resolved by recombinant E. coli(HcDDH-NOX) resting cells co-expression of an NADH oxidase(NOX), affording(S)-diols and(1 S, 2 S)-trans-diols in ≥99% ee. The synthetic potential of HcDDH was proved by E. coli(HcDDH-NOX) via kinetic resolution of racemic trans-1,2-indandiol on a 100 ml scale reaction,(S, S)-trans-1,2-indandiol was prepared in 46.7% yield and >99% ee. In addition, asymmetric reduction of four α-Hydroxy ketones(10–300 mmol·L^(-1)) by E. coli(HcDDH-GDH) resting cells resulted in >99% ee and69–98% yields of(R)-vicinal diols. The current research expands the toolbox of DDHs to synthesize chiral vicinal diols and demonstrated that the mined Hc DDH is a potential enzyme in the synthesis of a broad range of chiral vicinal diols. 展开更多
关键词 diol dehydrogenases Kinetic resolution ENANTIOSELECTIVE Chiral vicinal diols a-Hydroxy ketone
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Selective Monoprotection of Symmetrical Diols in a Flow Reactor
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作者 Hisashi Masui Masaru Takizawa +4 位作者 Yuki Sakai Yasuhiro Kajiwara Kiyofumi Wanibuchi Mitsuru Shoji Takashi Takahashi 《International Journal of Organic Chemistry》 2018年第2期264-271,共8页
Desymmetrization reactions provide a powerful approach for the construction of complex molecules. Various methods have been developed for the selective monoprotection of symmetrical diols;however, their application to... Desymmetrization reactions provide a powerful approach for the construction of complex molecules. Various methods have been developed for the selective monoprotection of symmetrical diols;however, their application to large-scale operations is limited. In this study, the monotetrahydropyranylation of symmetrical diols in a flow reactor has been developed, whereby the length of the flow reactor tube and the amount of acid were optimized. A higher selectivity for the monoprotected derivative was observed when the reaction was performed in a flow reactor compared with that observed in a conventional batch experiment. The efficient flow method developed herein can be applied to large-scale synthesis by numbering up the flow reactor without affecting the selectivity and yield. Since monoprotection can be achieved without using a large excess of diol, our developed flow method is effective when expensive diol must be used. 展开更多
关键词 DESYMMETRIZATION SELECTIVE Monoprotection FLOW Synthesis diols TETRAHYDROPYRANYLATION
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Facile Preparation of 1,2-Diols from Chalcones: An NMR Spectroscopy and X-Ray Crystallography Study
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作者 Marco A. Obregón-Mendoza María Miriam Estévez-Carmona +2 位作者 Carolina Escobedo-Martínez Manuel Soriano-García Raúl G. Enríquez 《International Journal of Organic Chemistry》 2015年第3期137-146,共10页
Structures of 2-(naphthalen-2-ylmethyl)-2,3-dihydro-1H-indene-1,2-diol (C20H18O2), compound 1 and 1-(3,4-dimethoxyphenyl)-3-methoxy-3-(4-nitrophenyl)propane-1,2-diol chloroform (C18H21NO7·CHCl3) compound 2 were e... Structures of 2-(naphthalen-2-ylmethyl)-2,3-dihydro-1H-indene-1,2-diol (C20H18O2), compound 1 and 1-(3,4-dimethoxyphenyl)-3-methoxy-3-(4-nitrophenyl)propane-1,2-diol chloroform (C18H21NO7·CHCl3) compound 2 were established by spectral and X-ray diffraction studies. Compound 1 crystallizes in the orthorhombic space group P212121 with unit cell parameters a = 5.2177 (6), b = 13.903 (2), c = 21.121 (2) A, Z = 4. Compound 2 crystallizes in the triclinic space group P-1 with unit cell parameters a = 9.238 (1), b = 9.879 (1), c = 12.636 (1) A, α = 102.004 (1), β = 92.356 (1), γ = 90.779 (1)o, Z = 2. These two new molecules arise from a facile preparation of 1,2-diols from chalcones and have been fully characterized. Based on the crystallographic information obtained for compound 1, the relative configuration for the chiral centers is 1S and 2S. In structure 1, both hydroxyl groups adopt an anti-conformation with a torsion angle O1-C1-C2-O2 value of 93.1 (2)o [in molecule 2, both hydroxyl groups adopt a trans-conformation with a torsion angle O1-C1-C2-O2 value of -171.0 (2)。]. In both structures, the molecules in the crystal are linked by intermolecular hydrogen bonds O-H···O and C-H···O interactions and adjacent molecules are interconnected by intermolecular weak C-H···π and C-H···Cl interactions which give additional support to molecular packing stability. 展开更多
关键词 C20H18O2 C18H21NO7·CHCl3 diols Chal-cones
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Spatial Distributions and Potential Sources of Long Chain(C_(30),C_(32)1,15-)Alkyl Diols in Surface Sediments from Eastern China Marginal Seas
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作者 YU Meng ZHANG Hailong +1 位作者 LI Li ZHAO Meixun 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1114-1122,共9页
Long chain alkyl diols have shown important potential for the reconstruction of sea surface temperature,productivities and upwelling conditions in marine or lacustrine environments.However,little is known about the di... Long chain alkyl diols have shown important potential for the reconstruction of sea surface temperature,productivities and upwelling conditions in marine or lacustrine environments.However,little is known about the distribution and sources of the diols in eastern China marginal seas(CMS),which are areas of important organic carbon sink.Here the contents of C_(30) and C_(32)1,15-diols were analyzed in 181 surface sediments from eastern CMS.The similar distribution pattern and strong linear correlation between C_(30) and C_(32) diols indicated that they had similar biological source,with a dominance of C_(30) diol.Their contents ranged from 7-2726 ng g^(-1) for C_(30) diol and 5-669 ng g^(-1) for C_(32) diol,and both showed higher values mainly in the mud area of the Yellow Sea,while the TOC normalized contents showed a more obvious seaward increasing trend.The similar distribution pattern and significant positive correlation between diols and the other marine biomarkers(brassicasterol,dinosterol,C_(37) alkenones) indicated C_(30) and C_(32) diols in eastern CMS were mainly from marine algae.This conclusion was also supported by principal component analysis(PCA).Our results also showed that sediment diol contents were generally related to marine productivity,suggesting that diols could be applied for marine productivity reconstruction in eastern CMS. 展开更多
关键词 long chain alkyl diols spatial distribution eastern China marginal seas marine biomarkers
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Two Chiral Building Blocks for the Stereocontrolled Synthesis of Anti-and Syn-1,3-Diols
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作者 Yong WU Mei GUAN +2 位作者 Zheng XU Li Cheng Xiao Chun WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第9期765-766,共2页
Two chiral building blocks 1 and 2 for anti-and syn-1, 3-diols has been achieved in 8 steps and 7 steps respectively, starting from the readily available and inexpensive D (+)-xylose 3.
关键词 Chiral building block anti-and syn-1 3-diols D (+)-xylose
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A Green Approach towards the Synthesis of Enantio Pure Diols Using Horse Radish Peroxidase Enzyme Immobilized on Magnetic Nanoparticles
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作者 Seelam Siva Deepthi Ernala Prasad +2 位作者 Basireddy Venkata Subba Reddy Bojja Sreedhar Adari Bhaskar Rao 《Green and Sustainable Chemistry》 2014年第1期15-19,共5页
Enantiopure epoxides and their corresponding chiral vicinal diols serve as valuable intermediates in the synthesis of biologically active pharma and agro-compounds and also value added fine chemicals. Biocatalysts are... Enantiopure epoxides and their corresponding chiral vicinal diols serve as valuable intermediates in the synthesis of biologically active pharma and agro-compounds and also value added fine chemicals. Biocatalysts are well known for their selective hydrolysis of racemic epoxides to give optically pure chiral diols. This study highlights an efficient process of synthesis of chiral vicinal diols in good yields and enantioselectiviy using horse radish peroxidase enzyme immobilized on the amine functionalized magnetic nano particles (Fe3O4 nanoparticles) as enzyme carriers. It also facilitates separation of MNP-immobilized enzymes by applying external magnetic field. The immobilization of magnetic nano particles was confirmed by transmission electron microscope (TEM) and scanning electron microscope (SEM). The MNP-immobilized peroxidase enzyme improved stability of the enzyme and has shown broader substrate specificity in enantioselective hydrolysis of racemic epoxides, under mild and environmentally friendly conditions. The methodology MNP-immobilized enzyme developed in the synthesis of chiral diols has a potential for use in large-scale applications. 展开更多
关键词 Magnetic Nanoparticles HORSERADISH PEROXIDASE Immobilization Vicinal-diols
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Solvent Effect of DMSO-d_6 on 1,2-Diols in ~1H NMR
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作者 LI Ting-you JIANG Shui-shi WANG Zong-mu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第6期761-762,共2页
There is a classic experiential rule about 1,2-diol RCR^1 (OH) CR^1 (OH) R( R^1 = H or methyl), that is, the proton chemical shift of the α-R^1 group at the hydroxvl group in the all-isomer, in general, aPPears... There is a classic experiential rule about 1,2-diol RCR^1 (OH) CR^1 (OH) R( R^1 = H or methyl), that is, the proton chemical shift of the α-R^1 group at the hydroxvl group in the all-isomer, in general, aPPears in a higher field with ca. 展开更多
关键词 1 2-diol ^1H NMR α-H atom X-ray crystallography
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Long-Chain Gemini Surfactant-Assisted Blade Coating Enables Large-Area Carbon-Based Perovskite Solar Modules with Record Performance
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作者 Yumin Ren Kai Zhang +5 位作者 Zedong Lin Xiaozhen Wei Man Xu Xianzhen Huang Haining Chen Shihe Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期463-477,共15页
Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable dep... Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable deposition of uniform defect-free perovskite films over large areas,which is an unsettled but urgent issue.In this work,a long-chain gemini surfactant is introduced into perovskite precursor ink to enforce self-assembly into a network structure,considerably enhancing the coverage and smoothness of the perovskite films.The long gemini surfactant plays a distinctively synergistic role in perovskite film construction,crystallization kinetics modulation and defect passivation,leading to a certified record power conversion efficiency of 15.46%with Voc of 1.13 V and Jsc of 22.92 mA cm^(-2)for this type of modules.Importantly,all of the functional layers of the module are printed through a simple and high-speed(300 cm min^(-1))blade coating strategy in ambient atmosphere.These results mark a significant step toward the commercialization of all-printable carbon-based perovskite solar modules. 展开更多
关键词 long-chain gemini surfactant Blade-coating Capillary number Carbon-based perovskite photovoltaics All-printable module
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Haplotype analysis of long-chain non-coding RNA NONHSAT102891 promoter polymorphisms and depression in Chinese individuals: A case-control association study
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作者 Yue Li Yi-Xi Wang +5 位作者 Xing-Ming Tang Peng Liang Jing-Jie Chen Feng Jiang Qiang Yang Yun-Dan Liang 《World Journal of Psychiatry》 SCIE 2023年第12期1005-1015,共11页
BACKGROUND Our previous study reported that the single-nucleotide polymorphism(SNP)rs155979 GC in the promoter region of long-chain non-coding RNA(lncRNA)NONHSAT102891 affects depression susceptibility in a Chinese po... BACKGROUND Our previous study reported that the single-nucleotide polymorphism(SNP)rs155979 GC in the promoter region of long-chain non-coding RNA(lncRNA)NONHSAT102891 affects depression susceptibility in a Chinese population.AIM To explored associations of two SNPs and haplotypes in the lncRNA NONHSAT102891 promoter region with depression susceptibility in Chinese population.METHODS This this case-control association study was approved by the Ethics Committee of Chengdu Medical College(approval number:201815).Patient diagnosis was based on DSM-IV criteria.We selected a total of 480 patients with depression and 329 healthy controls with no history of psychopathology,and performed genotyping of two SNPs by extracting peripheral venous blood samples from the subjects.The function of the two lncRNA NONHSAT102891 promoter G/C and A/T haplotypes was detected by dual-luciferase reporter assays of human embryonic kidney 293T transfected cells.RESULTS Stratified analysis of clinical and genotypic characteristics of our cohort showed that the degree of mild depressive episodes associated with the rs6230 TC/CC genotype increased by 1.59 times[TC/CC vs TT:odds ratio(OR)=1.59,95%confidence interval(CI):1.08-2.35,P=0.019].The haploid analysis revealed linkage disequilibrium between rs3792747 and rs6230,and the double SNP CG haplotype was more common in the control group compared to case group,indicating that this haplotype significantly reduced the risk of depression(C/G vs T/A:OR=0.42,95%CI:0.21-0.83,P=0.01).There was no significant difference in the dual-luciferase reporter activity of the G/C and A/T haplotypes compared with the control group(P>0.05),indicating that the double SNP haplotype has no transcrip-tional activity.CONCLUSION The rs3792747 and rs6230 CG haplotypes of the lncRNA NONHSA T102891 promoter may be related to a reduced risk of depression in the Han Chinese population. 展开更多
关键词 long-chain non-coding RNA NONHSAT102891 DEPRESSION SUSCEPTIBILITY Single-nucleotide polymorphisms HAPLOTYPE Transcriptional activity
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Synthesis and Antitumor Activity of 3-[2-(4-Hydroxy-Phenyl)-Ethyl]-Benzo[d] Isoxazole-4,6-Diol
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作者 Li Wang 《International Journal of Organic Chemistry》 CAS 2023年第1期1-6,共6页
A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characteriz... A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characterized by 1H NMR, 13C NMR and HR-MS. The phloretin, compound 1, resveratrol and acetylated resveratrol were determined by comparing them with paclitaxel. Anti-tumor activity of alcohol on SPC-A1, EC109, A549, MCF-7 and MDA-MB-231 cell lines. Compound 1 showed better antitumor activity than docetaxel against A549 tumor cells. 展开更多
关键词 3-[2-(4-Hydroxy-Phenyl)-Ethyl]-Benzo[d] Isoxazole-4 6-diol SYNTHESIS Antitumor Activity
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阻燃型水性聚氨酯乳液的制备及性能 被引量:1
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作者 朱港港 黄毅萍 +3 位作者 鲍俊杰 全晴晴 郑慧洁 赵雨楠 《塑料工业》 CAS CSCD 北大核心 2024年第1期29-35,共7页
以苯酐聚酯二元醇(PH-56)、聚己二酸新戊二醇酯(PNA)、异佛尔酮二异氰酸酯(IPDI)和二羟甲基丙酸(DMPA)等为基础原料,三羟甲基氧化磷(THPO)为交联剂,制备一系列改性水性聚氨酯乳液(ZWPU)。通过红外光谱仪(FTIR)表征胶膜的结构,同时测定... 以苯酐聚酯二元醇(PH-56)、聚己二酸新戊二醇酯(PNA)、异佛尔酮二异氰酸酯(IPDI)和二羟甲基丙酸(DMPA)等为基础原料,三羟甲基氧化磷(THPO)为交联剂,制备一系列改性水性聚氨酯乳液(ZWPU)。通过红外光谱仪(FTIR)表征胶膜的结构,同时测定胶膜的力学性能、阻燃性能等。结果表明,随着THPO添加量逐渐增加,胶膜铅笔硬度降低,极限氧指数和垂直燃烧呈现先增加后降低的趋势,热稳定性增加,耐水性降低;当THPO添加量为0.77%(占聚氨酯预聚体的质量分数)时,胶膜铅笔硬度为3H,附着力为0级,极限氧指数为24%,垂直燃烧等级为V-1,热释放速率降低了13.86%,拉伸强度为49.98 MPa,断裂伸长率为461.41%。 展开更多
关键词 苯酐聚酯二元醇 三羟甲基氧化磷 水性聚氨酯 阻燃
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聚乳酸基水性聚氨酯的制备及其在合成革中的应用研究 被引量:1
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作者 沈丹彤 薛雨亭 +2 位作者 李荣杰 徐芳 翁云宣 《中国塑料》 CAS CSCD 北大核心 2024年第4期19-25,共7页
以聚乳酸二元醇(PLA⁃OH)和六亚甲基二异氰酸酯(HDI)为原料,2,2⁃二羟甲基丁酸(DMBA)为亲水扩链剂合成了亲水扩链剂含量不同的聚乳酸(PLA)基水性聚氨酯(PLA⁃WPU)乳液,制备了PLA⁃WPU胶膜和超细纤维合成革。结果表明,随DMBA含量的增加,PLA⁃... 以聚乳酸二元醇(PLA⁃OH)和六亚甲基二异氰酸酯(HDI)为原料,2,2⁃二羟甲基丁酸(DMBA)为亲水扩链剂合成了亲水扩链剂含量不同的聚乳酸(PLA)基水性聚氨酯(PLA⁃WPU)乳液,制备了PLA⁃WPU胶膜和超细纤维合成革。结果表明,随DMBA含量的增加,PLA⁃WPU乳液粒径减小、固含量增大,PLA⁃WPU超细纤维合成革拉伸强度和最大负荷增大,水接触角减小。当DMBA含量为5.5%时,PLA⁃WPU乳液固含量达到35.4%,粒径为196.37 nm,PLA⁃WPU超细纤维合成革的拉伸强度提高到29.9 MPa,约为超细纤维基布的1.7倍,水接触角降低到73°。 展开更多
关键词 水性聚氨酯 聚乳酸二元醇 亲水扩链剂 超细纤维合成革
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Lactobacillus diolivorans二醇脱水酶激活因子基因的克隆、测序与功能鉴定 被引量:5
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作者 孟晓蕾 唐悦 +2 位作者 齐向辉 韦宇拓 黄日波 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2007年第1期87-92,共6页
根据二醇脱水酶与甘油脱水酶的激活因子基因序列同源性分析,设计简并引物从L.diolivorans基因组DNA中扩增出了假定的二醇脱水酶激活因子基因(gldG、gldH)全序列,补全了GenBank中该基因序列的未知部分,构建了表达质粒pSE-gldGH,以E.coliB... 根据二醇脱水酶与甘油脱水酶的激活因子基因序列同源性分析,设计简并引物从L.diolivorans基因组DNA中扩增出了假定的二醇脱水酶激活因子基因(gldG、gldH)全序列,补全了GenBank中该基因序列的未知部分,构建了表达质粒pSE-gldGH,以E.coliBL21为宿主,进行诱导表达.表达产物的变性与非变性聚丙烯酰胺凝胶电泳分析表明:gldGH表达产生68ku、13ku两个蛋白质,它们经金属螯合亲和层析与凝胶过滤得到共纯化,纯化产物即假定的激活因子为分子质量约325ku的蛋白质聚合体,由这两个蛋白质以等摩尔量组成,因此假定的激活因子可能为α4β4亚基结构.以L.diolivorans二醇脱水酶为对象,进行激活实验,结果证实gldGH表达产物具备二醇脱水酶激活因子的功能. 展开更多
关键词 二醇脱水酶 激活因子 功能鉴定 1 3-丙二醇 LACTOBACILLUS diolivorans
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癸炔二醇生产过程中钾盐的回收研究
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作者 彭小双 蒋文伟 +2 位作者 杨友国 张潆心 张艳 《现代化工》 CAS CSCD 北大核心 2024年第S01期275-279,283,共6页
采用实验室制备的含炔醇的碱液,探究活性炭吸附碱液中有机物的规律及吸附的最佳条件,并回收碱液中的钾离子得到优级纯硫酸钾产品。结果表明,活性炭吸附的最佳条件为:吸附温度为40℃、活性炭用量为2 g/100 mL、pH为5、吸附时间为40 min;p... 采用实验室制备的含炔醇的碱液,探究活性炭吸附碱液中有机物的规律及吸附的最佳条件,并回收碱液中的钾离子得到优级纯硫酸钾产品。结果表明,活性炭吸附的最佳条件为:吸附温度为40℃、活性炭用量为2 g/100 mL、pH为5、吸附时间为40 min;pH为5时,溶液中的酯类有色物质会发生分解从而大幅度提高活性炭对有机物的去除率。 展开更多
关键词 癸炔二醇 吸附 硫酸钾 有机废水 盐的回收
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过渡金属多相催化分子氧选择性氧化邻二醇的研究进展
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作者 尹钧濂 冯冉冉 +1 位作者 张月成 赵继全 《精细化工》 EI CAS CSCD 北大核心 2024年第5期943-950,959,共9页
邻二醇选择性氧化断键生成醛、酮和羧酸是重要和基本的有机反应,氧化剂通常采用化学计量的高碘酸盐或四乙酸铅,无论从经济还是环保的角度考虑,这些传统方法都有违绿色化工的发展理念。理论上以分子氧为氧化剂选择性氧化邻二醇断键的副... 邻二醇选择性氧化断键生成醛、酮和羧酸是重要和基本的有机反应,氧化剂通常采用化学计量的高碘酸盐或四乙酸铅,无论从经济还是环保的角度考虑,这些传统方法都有违绿色化工的发展理念。理论上以分子氧为氧化剂选择性氧化邻二醇断键的副产物只有水,而且分子氧廉价易得,因而具有环境友好和经济可行的双重优势。经过多年探索,人们已开发了多个基于不同过渡金属为活性组分的多相催化剂或催化体系用于分子氧选择性氧化邻二醇断键反应,为未来广泛应用奠定了基础。该文按贵金属和非贵金属分类综述此类催化剂及相关反应工艺的研究进展,并指出该领域的发展方向。 展开更多
关键词 邻二醇 氧化断键 分子氧氧化 过渡金属 多相催化剂
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