Construction of a 2,6-difunctionalized 2-methyl-2H-1-benzopyran library by using a solid-phase synthesis protocol

[reaction: see text] A library containing 1200 analogues of 2,6-difunctionalized 2-methyl-2H-1-benzopyran was constructed by using a solid-phase synthesis protocol. Polymer-bound 6-amido-, 6-sulfonamido-, and 6-uredo-functionalized 2-hydroxymethyl-2-methylbenzopyrans 10 were prepared as part of a first-generation diversification step by employing reactions of respective acid halides, sulfonyl chlorides, and isocyanates with the amine precursor 7. Transformations of the resin-bound intermediates 10 by reactions with alkyl and acid halides were then used to produce a diverse series of 2,6-difunctionalized 2-methyl-2H-1-benzopyran analogues 12 and 14.     

活性碳分离碳－60和碳－70

活性碳用苯胺处理后，可以减少对Ｃ＿（６０）和Ｃ＿（７０）的不可逆吸附，从而增加Ｃ＿（６０）和Ｃ＿（７０）的分离收率，同时提高了Ｃ＿（７０）的纯度。     

氯代十六烷基吡啶存在下钯与1，4－双肼酞嗪新显色反应的研究

本文研究了１，４－双肼酞嗪（ＤＨＰＨ）与钯的配合显色反应，在阳离子型表面活性剂氯代十六烷基吡啶存在下，在０．１～０．２ｍｏｌ／ＬＨＣｌ溶液中，试剂与钯形成１：１的稳定的黄绿色配合物，最大吸收峰在４００ｎｍ处，表观摩尔吸光系数为２．６×１０￣４，钯量在０～５０μｇ／２５ｍＬ范围内股从比尔定律，方法简便快速，选择性好，已用于催化剂中钯的测定，结果满意。     

Preparation and structural characterization of the hexatungsten cluster complex (EDTEH)2[W6(μ3-Cl)8Cl6], (EDTEH=(MeO2CCH2)2N(H)CH2CH2N(CH2CO2Me)2+

The hexanuclear tungsten cluster complex [W₆(₃-Cl)₈Cl₆]^2–,1 was isolated as a salt of the cation (MeO₂CCH₂)₂N(H)CH₂CH₂N(CH₂CO₂Me)₂₊, EDTEH⁺, by crystallization from methanol solvent of the product obtained from the reaction of (H₃O)₂[W₆(₃-Cl)₈Cl₃] with the disodium salt of ethylenediaminetetraacetic acid. The compound was charcterized by single-crystal X-ray diffraction analysis. The cluster anion contains an octahedral arrangement of six tungsten atoms with chloride ligands bridging the eight triangular faces of the cluster and one chloride ligand terminally coordinated to each of the six tungsten atoms. The cation (EDTEH)⁺ achieves its positive charge by protonation of one of the nitrogen atoms. Crystal data: space group = P2₁/a,a=10.689(2) Å,b=22.931(6) Å,c=12.093(3) Å, =98.41(2)°,Z=2, 2476 reflections,R=0.028.     

A New Brominated Phenylpropylaldehyde and its Dimethyl Acetal from Red Alga Rhodomela confervoides

A new brominated phenylpropylaldehyde and its dimethyl acetal together with a new natural brominated phenol were isolated from Rhodomela confervoides. Their structrues were elucidated as 2-methyl-3-(2,3-dibromo-4,5-dihydroxyphenyl)propylaldehyde, 2-methyl-3-(2,3-di-bromo-4,5-dihydroxyphenyl) propylaldehyde dimethyl acetal and 3-bromo-4,5-dihydroxybenzoic acid methyl ester by spectroscopic techniques including IR, HRFABMS, 1D and 2DNMR experiments.     

Plasmid DNA isolation using amino-silica coated magnetic nanoparticles (ASMNPs)

A simple and efficient approach for the rapid isolation of plasmid DNA from crude cell lysates has been described. The approach took advantage of the amino-modified silica coated magnetic nanoparticles (ASMNPs) with positive zeta potential at neutral pH and superparamagnetism under the external magnetic fields. As a demonstration, the pEGFP-N3 plasmid has been concentrated and isolated from the E. coli DH5α transformed with pEGFP-N3 plasmid through electrostatic binding between the positive charge of the amino group of ASMNPs and the negative charge of the phosphate groups of the plasmid DNA. Then the pEGFP-N3 plasmid has been released easily and quickly from the pEGFP-N3 plasmid-ASMNPs complexes with 3 M NaCl. The entire procedure could be carried out by the aid of external magnetic fields in 15 min and eliminate the need of phenol, cesium chloride gradients or other noxious reagents and complexes operation. Moreover, the pEGFP-N3 plasmid obtained by this approach retains biological activity that can be suitable for restriction enzyme digestion and cells transfection with expression of green fluorescence protein.     

Highly efficient, one-step macrocyclizations assisted by the folding and preorganization of precursor oligomers

Highly efficient, one-step macrocyclizations leading to the formation of macrocyclic hexa(aramides) in high yields (69-82%) are described. The one-step macrocyclizations were facilitated by the preorganization or folding of the backbones of uncyclized precursors in the course of macrocyclization. The preorganization of backbones was achieved by the presence of localized three-centered hydrogen bonds that were adopted in the design of a class of closely related, backbone-rigidified foldamers. The macrocyclization involved reactions between diacid chloride 1 and diamine 2. The crude reaction mixtures and products were conveniently examined by mass spectrometric method (MALDI-TOF). Compared to most traditional one-step macrocyclizations that usually require high dilution conditions and often lead to very low overall yields of the desired products, cyclic hexamers 3 were obtained as the overwhelmingly major product under a variety of reaction conditions, suggesting the generality of this approach.     

高岭石吸附乙烯和苯的Delft分子力学研究

运用Ｄｅｌｆｔ分子力学（ＤＭＭ）程序及其粘土和共轭烯烃力场，计算研究了高岭石对乙烯和苯的吸附作用，探讨了吸附对粘土晶体和有机分子的结构、电荷分布和能量的影响，求得了高岭石吸附乙烯和苯的吸附热等重要物理量．     

Waterborne polyurethane assembly multifunctional coating for hydrophobic and antibacterial fabrics

Surface modification of fabrics is a powerful strategy that can endow fabrics with desired effects while keeping the intrinsic properties. Herein, an ordinary strategy, dipping-drying based layer-by-layer self-assembly (LbL) coating, is reported to functionalize fabrics’ surfaces. Firstly, the novel cation waterborne polyurethanes (QAHDPU) and anion waterborne polyurethanes (HDPU) are successfully designed and synthesized. By incorporating targeted molecule, hydantoin diol (HD) and quaternary ammonium salt with long alkyl chain (DOQA), the QAHDPU are antibacterial and hydrophobically functionalized. Taking advantage of strong adhesion, waterborne polyurethanes (WPUs) are physically bonded to surfaces of fabrics to generate durable antibacterial and hydrophobic fabrics. The QAHDPU with long alkyl chain combined with rough and porous fabric surface fabricates hydrophobic fabric surface, which can prevent bacteria from adhering to the fabrics. Furthermore, the coated fabrics present excellent antibacterial properties after chlorination, forming a second barrier against bacteria. The chlorinated coated fabrics, can inactivate 85.0–99.9% of Staphylococcus aureus and 85.0–97.7% of Escherichia coli with contact time of 60 min. The hydrophobic properties of coated fabrics are greatly improved with water contact angles of 122.0°–141.1°. In addition, the proposed method is applicable for a variety of fibers and expected to be used for industrial production.

Graphical abstract

     

纳米微晶Y_2Sn_(2-x)FexO_(7-δ)的制备及其催化选择性能研究

采用共沉淀并加法制备了Ｂ位掺杂烧绿石型稀土复合氧化物纳米微晶Ｙ２Ｓｎ２－ｘＦｅｘＯ７－δ（ｘ＝００～１０）。制备的纳米微晶属于立方晶系，Ｆｄ３ｍ，晶胞参数与掺杂量呈线性关系。通过Ｍｓｂａｕｅｒ、ＴＧＤＴＡ，气相色谱和γ射线辐照等技术研究了纳米微晶对ＣＯ的催化选择性能。结果表明，纳米微晶对ＣＯ的催化选择性明显高于一般粉料对ＣＯ的选择性；纳米微晶对ＣＯ的选择性与掺杂量有关；未辐照的纳米微晶，当掺杂量ｘ＝０６时，其对ＣＯ的选择性为最高，辐照后的纳米微晶，当掺杂量ｘ＝０４时，其对ＣＯ的选择性为最高