Hydrophobic CHA-ZIFs with a junctional trap between cha and d6r cages for adsorption of 2,3-butanediol in aqueous solution

The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic imidazolate frameworks(ZIFs) with chabazite(CHA) topology for separation of 2,3-butanediol(2,3-BDO) and 1,3-propanediol(1,3-PDO), which had junctional and hydrophobic traps matching the two end methyl groups of the 2,3-BDO molecule. Based on CHA-ZIFs with the same small-sized ligand 2-methylimidazole(mIm) and different large-sized ligand benzimidazole derivatives(RbIm),CHA-ZIFs with larger surface areas were obtained by the addition of excess small-sized ligand mIm in the synthesis process. We showed that all of the hydrophobic CHA-ZIFs preferentially adsorbed 2,3-BDO over 1,3-PDO by static batch adsorption and dynamic column adsorption experiments. But ZIF-301 and ZIF-300 with halogen groups exhibited better adsorptive separation performance for 2,3-BDO/1,3-PDO than ZIF-302 with methyl groups. For a typical ZIF-301, its adsorption capacity for 2,3-BDO was 116.4 mg·g^(-1)and selectivity for 2,3-BDO/1,3-PDO was 3.8 in dynamic column adsorption of the binary-component system(2,3-BDO/1,3-PDO: 50 g·L^(-1)/50 g·L^(-1)). Computational simulations revealed that 2,3-BDO preferentially adsorbed in a trap at the junction between the cha and d6r cages of CHA-ZIFs,meaning the strong host-guest interactions. Therefore, the hydrophobic CHA-ZIFs with a junctional trap were promising candidate materials for adsorbing 2,3-BDO, which also provided a new perspective for separating diols in dilute aqueous solutions.

Lactobacillus diolivorans二醇脱水酶激活因子基因的克隆、测序与功能鉴定

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.

Lactobacillus diolivorans二醇脱水酶的分离纯化与酶学性质

1，3-丙二醇（1，3-propanediol，1，3-PD）是一种重要的化工和医药中间体原料，是良好的溶剂、抗冻剂或保护剂，是聚酯——聚对苯二甲酸丙二醇酯（PTT）和聚氨酯的单体，可在地毯、纺织、工程塑料等领域中广泛应用，也可用于食品、化妆品和制药等行业食品．当前化工合成是生产1，3-丙二醇的主要方法，

Synthesis and characterization of yellow water-borne polyurethane using a diol colorant as extender

A novel and facile method toward a series of yellow water-borne polyurethane was developed by using an intrinsically colored diol in this paper.The yellow aqueous dispersion PCLD-HENA-PU was synthesized based on isophorone diisocyanate(IPDI), polycaprolactonediol(PCLD) and 2,2-dimethylol propionic acid(DMPA) using a yellow diol N,N-bis(2-hydroxyethyl)-4-nitroaniline (HENA) as a chain extender.Due to the complete reaction of OH group in colorant HENA with NCO group in diisocyanate,a series of stable yellow p...

Selective Hydrogenation of Butyne-1,4-diol to Butane-1,4-diol over Ni/Al_2O_3-SiO_2 Catalysts

Ni/Al_2O_3-SiO_2 catalysts were synthesized via one-step method employing SiO_2 as an additive for the selective hydrogenation of butyne-1,4-diol(B_3D) to butane-1,4-diol(B1D). The prepared catalysts were evaluated by a series of characterization techniques including BET, XRD, SEM, EDX-mapping, TEM, H_2-TPR, XPS, NH_3-TPD and Py-FTIR. Compared to Ni/Al_2O_3 catalyst, the SiO_2-doped samples exhibited better B_3D conversion. SiO_2 could help to form a strong interaction between NiO with the support, which inhibited Ni agglomeration at high temperature, improved the Ni dispersion, and enhanced the hydrogenation activity. B_1D selectivity was mainly influenced by the quantity of Lewis acid sites in addition to the Ni dispersion. The catalyst with a silica loading of 6.4% demonstrated an excellent selectivity of 75.18%(by 13% higher than the contrastive Ni/Al_2O_3 catalyst), which was attributed to the larger amount of Lewis acid sites and the moderate interaction between NiO with the support, which could facilitate the nickel dispersion on a preferable surface area of 176.3 m^2/g of support.

Ent-Kauran-16β,17-diol碳信号的修正及其意义

作者针对文献关于 ent- kauran- 16 β,17- diol( )碳信号指认有误的问题 ,用化学合成方法和 2 D-NMR技术对 的结构进行全面分析和论证 ,首次归属了每个氢质子的信号 ,并再次证实其结构中的 C- 1、C- 7和 C- 14互为颠倒 ,该研究对 ent-

Characterization of four diol dehydrogenases for enantioselective synthesis of chiral vicinal diols

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.

Cytotoxicity of Benzo(a)pyrene 7,8-dihydrodiol on Genetically Engineered V79 Chinese Hamster Cells Expressing Rat Liver Cytochrome P450 1A1

To develop well defined in vitro cell system to test cytotoxicity of a number of model toxins, genetically engineered V79 Chinese hamster fibroblasts expressing isoenzymes of cytochrome P4501A1 XEM2 cells and V79 cells (parental), which lack cytochrome P450 enzyme activities, were used as controls. The cytotoxic effect of trans 7,8 dihydrbenzo(a)pyrene (BP 7,8 diol) on the parental cells V79 and V79 derived XEM2 cells were evaluated by two methods for cell viability. The data obtained expressed that BP 7,8 diol ranging from 1.0 μmol·L 1 to 5.0 μmol·L 1 in concentrations incubated for 24 h showed a strong cytotoxic effect in XEM2 cells (expressing rat cytochrome P4501A1) in a concentration dependent manner. Time dependent decrease for survival of XEM2 cells was also observed at 2.5 μmol·L 1 concentration. Likewise, BP 7,8 diol did not alter the survival of the parental cells V79 under the same condition. This study also showed that α naphthoflavone (αNF), a well known inhibitor of cytochrome P4501A1 might alter BP 7,8 diol induced cytotoxicity in the XEM2 cells. Our results suggested that cytochrome P4501A1 is responsible for BP 7, 8 diol induced cytotoxicity.

Isolation and Crystal Structure of Stigmast-4-ene-3,6-diol

The title compound (C29H50O2, Mr = 430.69) was isolated from the algae Halimeda xishaensis collected from the South China Sea. Its crystal structure was determined by single-crystal X-ray diffraction for the first time. The crystal belongs to orthorhombic, space group P212121 with a = 8.1560(13), b = 10.7861(18), c = 29.973(5) ? V = 2636.8(8) 3, Z = 4, Dc = 1.085 g/cm3, F(000) = 960, (Mo-K? = 4.533 mm-1, ?= 0.71073 ? S = 1.061, (?max = 0.382 and (?min = 0.244 e/?. The structure was refined to R = 0.0561 and wR = 0.1553 for 2711 observed reflections with I > 2(I). X-ray diffraction analysis reveals that the title compound has two ?OH groups, and the side chain is saturated. There exist two intermolecular hydrogen bonds between three molecules.

Synthesis and application of an IL-supported diol as protecting group for aldehydes

A new IL-supported diol, 1-（2,3-dihydroxypropyl）-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS （ESI）. Its physical properties such as freezing point, solubility and specific gravity and thermal stability were determined. Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated.

INFLUENCE OF 2-BUTYNE-1,4-DIOL ON THE STRUCTURE AND PERFORMANCE OF THE Co-Ni ALLOY PLATED BY ELECTRODEPOSITION

The effect of 2-butyne-1, 4-diol （BD） on the deposition behavior of the Co-Ni alloy was investigated by linear sweep voltammetry. The results showed that BD could prevent the deposition of the Co-Ni alloy. The effect of BD concentration in the sulfate plating bath, on the structure of the Co-Ni deposit was studied by energy dispersive x-ray spectroscopy, scanning electron microscope, and X-ray diffraction, respectively. As a result, BD could smoothen the deposit surface and decrease the diameter of the grain, but too much of BD was not good for the size of the grain. In general, a hexagonal close-packed （hcp） phase of the Co-Ni alloy, with a preferentially oriented （110） plane, was prepared by electrodeposition in the presence of BD. The Co-Ni alloy as a catalyst for the electro-oxidation of ethanol in alkaline medium was investigated by cyclic voltammetry. The deposit plated from the bath containing BD possessed better electro-oxidation of ethanol performance compared with that of the deposit plated from only the sulfate plating bath, but too much of BD was not beneficial for catalytic activity. The Co-Ni film was suitable as a magnetic recording material.

In vitro antioxidant and antimicrobial activity cycloart-23-ene-3β,25-diol(B2) isolated from Pongamia pinnata(L.Pierre)

Objective:To evaluate the in-vitro antioxidant and antimicrobial activity of cvcloart-23- ene-3β,25-diol(called as B2) isolated from stem bark of Pongamia pinnata.Methods:In vitro antioxidant activity of B2 was determined by methods for determination of Dl’PH radical scavenging,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging, hydrogen peroxide scavenging,metal chelating and nitric oxide radical scavenging at the doses of 20.40.60.80 and 100μg/mL,respectively.3 -tocopherol with same concentration was used as a standard antioxidant.In vitro antimicrobial activity of B2 was determined by cup plate method in different concentration range of 10-100μg/mL.Results:The results indicated that dose dependent%reduction against DPPH radical,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging,metal chelating,hydrogen peroxide scavenging and nitric oxide radical scavenging by B2 andβ-tocopherol.Conclusions:It is concluded that cycloart 23-ene-3β,25 diol(B2) showed dose dependent antioxidant activity.B2 showed more DPPH radical scavenging,reducing power,superoxide scavenging,hydroxyl radical scavenging, metal chelating scavenging,hydrogen peroxide radical scavenging and nitric oxide radical scavenging activity thanβ-tocopherol and in case of antimicrobial activity B2 exhibited broad-spectrum activ ity against bacteria and strong activity against yeast type of fungi.

Crystal Structure of (6S,9S,13R,14S)-7,8-Didehydro-3,7-dimethoxy-17-methylmorphinan-4,6-diol

The title compound (C19H25NO4, Mr = 331.40) was synthesized and its crystal structure was determined by single-crystal X-ray structure analysis. The compound belongs to space group P212121 with a = 7.738(2), b = 10.131(2), c = 21.535(4) ? V = 1688.3(6) 3 and Z = 4. The final R and wR factors are 0.0557 and 0.1489, respectively for 2936 (I > 2s(I)) independent observable reflections. The result shows that the title compound is a tetracyclic alkaloid with four chiral centers, and the absolute configuration of the newly formed one is 6S. The piperidine ring is in chair conformation, while the other two aliphatic rings are in twist boat conformation. The title compound was the mainly isolated reduction product, which means that the hydrogen anion attacks the carbonyl group at the opposite side away from the phenyl group because of its steric effect.

Effect of 2-butyne-1, 4-diol on silver electrodeposition from 5, 5-dimethyl hydantoin solutions

The effect of 2-butyne-1, 4-diol on silver electrodeposition process from 5, 5-dimethyl hydantoin solutions was investigated by means of cyclic voltammetric measurement, scanning electron microscopy (SEM) and X-ray diffraction (XRD). Cyclic voltammetric studies indicate that the reduction process of silver electrodeposition is influenced by adding 2-butyne-1, 4-diol. Owing to its adsorption on the electrode surface, 2-butyne-1, 4-diol moderately hinders the mass transfer of the silver complexed ions from the bulk solution to the outer limit of the electrode double layer and affects the electrocrystallization step. Scanning electron microscopy analysis reveals that the presence of 2-butyne-1, 4-diol in the electrolyte is beneficial and the silver deposits obtained are smoother, more compact and more leveled. X-ray diffraction analysis of the silver deposits obtained at 0.5 g·L-1 2-butyne-1, 4-diol indicated that the (110) plane is the most preferred plane and is not affected by the presence of 2-butyne-1, 4-diol in the electrolyte.

Synthesis of Novel Chiral Diol Ligands for the Enantioselective Reactions

A series of novel enantiomerically pure diols were synthesized from D-erythorbic acid in three steps, and the absolute configuration of one of them 4a has been confirmed by X-ray analysis.

Preparation for Supramolecular Complexes of Chiral Diols BDPDD, DMBDPD and BINOL with Some Prochiral Compounds

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.

Selective monotetrahydropyranylation of symmetrical diols using P_20_5/Si0_2 under solvent-free conditions and their depyranylation

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.

Synthesis and characterization of new polyesters based on 2,5-bis[(4-chloro carboxyanilino)carbonyl]pyridine and aromatic diols

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 ...

PROPERTIES OF POLYURETHANE ELASTOMERS BASED ON POLY (OXYETHYLENE-co-OXYTETRAMETHYLENE) DIOL

Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization using heteropolyacid-ethylene oxide initiator system, were prepared. The polyurethanes exhibited an increased water absorption and much better low temperature resilience, which remained high even at a temperature of -3 degreesC, while that of polyurethane based upon poly(tetramethylene ether) glycol of the 'same molecular weight, i.e. being 2000, and molecular weight distribution, i.e, in the range of 1.4-1.5, starts to decrease dramatically at 5 degreesC.

Elimination Reaction of α,ω-Diols by Magnesium

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.