A contribution to the study of the modified Marschalk reaction:Hydroxymethylation of 6,8-O-dimethyl emodin

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.

Increase of Lignin Reactivity by Means of Depolymerization and Hydroxymethylation for Its Use in Synthetic Wood Elaboration

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.

Epigenetics in psychiatry:Beyond DNA methylation

The global burden of psychopathologies appears to be underestimated,since the global psychiatric disorder burden is exceeding other medical burdens.To be able to address this problem more effectively,we need to better understand the etiology of psychiatric disorders.One of the hallmarks of psychiatric disorders appears to be epigenetic dysregulation.While some epigenetic modifications(such as DNA methylation)are well known and studied,the roles of others have been investigated much less.DNA hydroxymethylation is a rarely studied epigenetic modification,which as well as being an intermediate stage in the DNA demethylation cycle is also an independent steady cell state involved in neurodevelopment and plasticity.In contrast to DNA methylation,DNA hydroxymethylation appears to be related to an increase in gene expression and subsequent protein expression.Although no particular gene or genetic locus can be at this point linked to changes in DNA hydroxymethylation in psychiatric disorders,the epigenetic marks present good potential for biomarker identification because the epigenetic landscape is a result of the interplay between genes and environment,which both influence the development of psychiatric disorders,and because hydoxymethylation changes are particularly enriched in the brain and in synapse-related genes.

One-pot synthesis of 2,5-bis(hydroxymethyl)furan from biomass derived 5-(chloromethyl)furfural in high yield

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.

三棱的化学成分研究

目的:研究三棱Sparganium stoloniferumBuch.-Ham.的化学成分。方法:采用硅胶柱层析,Sephadex LH-20,ODS C-18,重结晶等方法,根据理化性质和光谱鉴定化合物的结构。结果:从三棱中得到8个化合物,分别为棕榈酸(1),5-羟甲基糠醛(2),6,7,10-三羟基-8-十八烯酸(3),棕榈酸单甘油酯(4),5-Hydroxy-2-(hydroxymethyl)pyridine(5),β-谷甾醇(β-sitosterol)(6),β-胡萝卜苷(daucosterol)(7),Betulinic acid(8)。结论:化合物5,8为首次从该植物中分离得到。

Hrd1转基因小鼠的构建与验证

背景 内质网应激在糖尿病视网膜病变（DR）中发挥着重要作用.羟甲基戊二酰辅酶A还原酶降解蛋白1（Hrd1,又名Syvn1）作为一种内质网相关蛋白降解（ERAD）途径中的核心蛋白,能够减少内质网应激. 目的 构建Hrd1高表达小鼠,为今后研究Hrd1在DR中的作用提供动物模型. 方法 构建Hrd1系统表达重组质粒,酶切、测序后显微注射3 p1到685枚C57BL/6小鼠受精卵中,移植到代孕母鼠,得到Hrd1转基因小鼠.利用鼠尾PCR检测法鉴定F0代小鼠的基因型.得到Hrd1基因检测阳性鼠后,使其分别与野生型鼠杂交,得到F1代Hrd1转基因小鼠,取鼠尾组织,用PCR检测法再次鉴定F1代小鼠基因型. 结果 成功构建了Hrd1重组载体,重组质粒pRP.ExBi-EF1 a-Syvn1-IRES-eGFP的全序列测定结果显示,cDNA序列均正确.接受了Hrd1-pcDNA显微注射的685枚受精卵中成活598枚.将存活的受精卵移植到代孕母鼠后共产子鼠41只,获F0代子鼠8只,生理活动均良好.PCR电泳显示339 bp处阳性条带,该基因型可以传递到子代F1.结论 成功构建了Hrd1转基因小鼠.

Kaiso mainly locates in the nucleus in vivo and binds to methylated,but not hydroxymethylated DNA

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.

Preparation of natural α-tocopherol from non-α-tocopherols

Non-a-tocopherols are hydroxymethylated and hydrogenated to produce α-tocopherol in one pot process by simultaneously reacting with paraformaldehyde and hydrogen in the presence of catalysts of benzenesulfonic acid and 5% Pd/C in an autoclave. Effects of various operation conditions have been studied. The preferable reaction conditions are: temperature 180 ℃ to 200 ℃, pressure 5.0 MPa, acid concentration 0.5 g/100 ml ethanol, mass ratio of Pd/C to tocopherols 7.1 g/100 g, and reaction time 5.0 h. A product with α-tocopherol content of 80% was obtained by using a raw material with a total tocopherols content of 80.54%. The conversion of non-α-tocopherols is almost 100%, and the mole yield of a-tocopherol is more than 90%.

Synthesis and Structural Characterization of 2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol

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.

Complexation Between Borate ion and Hydroxyl Groups of Phenol-Formaldehyde Resol Resin

The complexation reaction between borate ions and phenol-formaldehyde resol resin in aqueous solution was studied by pH measurement, small model molecules and infrared spectroscopy. The results show that the complexation can proceed completely and rapidly at room temperature. Borate ion attacks phenol hydroxyl groups and adjacent position hydroxymethyl groups on the phenol ring of the resin, and forms the coordinate bond between boron atom in borate ion and oxygen atom in the hydroxyl groups. The complexation is a quantitative reaction. The complex is a six member ring containing two oxygens and one boron. The complexation can release hydrogen ions resulting in the decreasing pH in the resin solution.

Oxidation of 2,5‐bis(hydroxymethyl)furan to 2,5‐furandicarboxylic acid catalyzed by carbon nanotube‐supported Pd catalysts

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.

Helical Coordination Polymer with a 3-Fold Interpenetration Structure Based on 5-(Hydroxymethyl)isophthalic Acid

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.

Catalyst design strategy toward the efficient heterogeneously-catalyzed selective oxidation of 5-hydroxymethylfurfural

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.

Synthesis and Crystal Structure of 3,9-Bis(pyridin-2-yl)-2,4,8,10-tetraoxaspiro[5.5]undecane

The title compound 3,9-bis（pyridin-2-yl）-2,4,8,10-tetraoxaspiro[5.5]undecane 4（C17H18N2O4） has been synthesized by the reaction of 2,2-bis（hydroxymethyl）propane-1,3-diol with pyridine-2-carbaldehyde in the presence of p-toluenesulfonic acid,and characterized by IR,1H-NMR and X-ray single-crystal diffraction.The crystal belongs to monoclinic system,space group C2/c with a = 25.133（2）,b = 5.7219（5）,c = 21.942（2）（A°） ,β = 99.145（2）°,V = 3115.3（5）（A°）^3,Z = 8,Dc = 1.340 g/cm^3,Mr = 314.33,F（000） = 1328,μ = 0.097 mm-1,MoKa radiation（λ = 0.71073）,R = 0.0352 and wR = 0.1022 for 2486 observed reflections with I 〉 2σ（I）.X-ray analysis reveals that the two 1,3-dioxane rings passing through the central spiro-C atom both adopt chair conformation.Intermolecular C-H…π,C-H…O and C-H…N weak interactions link the molecules to form a three-dimensional samdwich,which are effective in the stabilization of the crystal structure.

Synthesis of 9,9′-Bis(methoxymethyl)fluorene

This paper describes the procedures for the facile synthesis of 9,9′-bis(methoxymethyl)fluorene using fluorene as starting material. By hydroxymethylation and etherification reaction, the fluorene can be converted to desired products with high yield and purity. The optimum conditions of the synthetic procedures were determined. For hydroxymethylation, the reaction temperature was 13 ℃and the mole ratio of sodium methoxide to paraformaldehyde was 0.26; and for etherification, the reaction temperature was 40 ℃and the reaction time was 15 h. Under the optimum conditions, an overall yield of 580 0 and purity of 99.20 0 were obtained.

<i>Streptomyces zerumbet</i>, a Novel Species from <i>Zingiber zerumbet</i>(L.) Smith and Isolation of Its Bioactive Compounds

Streptomyces zerumbet W14, a novel species of the endophyte genus Streptomyces was isolated from the rhizome tissue of Zingiber zerumbet (L.) Smith. Identification of strain W14 was based on its morphology, chemotaxonomy and phylogenetic analysis using 16S rDNA sequence. It was classified as the secondary meabolites of the culture extract were studied. The major active ingredients from the crude extract were purified by silica gel column chromatography and identified by spectroscopic data. The crude extract and purified compounds were tested for their biological activities on antibacterial and anti-inflammatory properties. The crude extract showed inhibition on the growth of Gram-positive bacteria with the MIC and MBC values of 8 - 32 μg/ml and 32 - 128 μg/ml, respectively. The isolated compounds were identified to be methyl 5-(hydroxymethyl)furan-2-carboxylate (1) and geldanamycin (2). Bioassay studies showed that compound 1 had antibacterial activity against Staphylococus aureus ATCC 25923 and Methicillin Resistant S. aureus strain Sp6 (clinical isolate) with the MIC and MBC values of 1 μg/ml and 16 - 64 μg/ml, respectively, and also showed activity against Bacillus Calmette-Guérin (vaccine strain) with MIC and MBC values of 128.00 μg/ml and 128.00 μg/ml, respectively. The compound 2 at the concentration of 1 - 5 μg/ml had in vitro anti-inflammatory activity on LPS-induced RAW 264.7 cells by inhibition of mRNA expression and production of inducible NO synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). These results suggest that compounds 1 and 2 produced by S. zerumbet W14 (an endophyte of Z. Zerumbet) have antibacterial and anti-inflammatory activities, respectively. Therefore, the future studies on these compounds could be useful for the management of bacterial infections and inflammatory diseases.

STUDIES ON THE TOTAL SYNTHESIS OF（－）－（2R，5S）－2－METHYL－5－HYDROXYMETHYL－δ－VALEROLACTONE

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.