Syntheses, Structures and Coordination Behavior of Central Hydroxyl Group Containing Polydentate Ligands

Proteins containing dinuclear Cu (II), Zn (II) centers play paramount roles in biology1. As mimetic of metal-dependent esterase, dinuclear Cu (II) and Zn (II) complexes have received a great deal of attentions2~6. They are of interest in the field of biomimetic chemistry to provide an improved understanding of the function of the biological sites and as potential catalysts for substrate oxidations. Schiff base type polydentate ligands which contain centeral hydroxyl group have been wid…     

Micro-droplet detection and characterization using thermal responses

We suggest a novel method to detect droplets and determine the protein content of droplets in microfluidic system using the 3ω method, which is a powerful tool to easily detect thermal response changes with a simple device. By measuring the thermal response of droplets and a carrying flow in real time, water droplets in an oleic acid carrying flow can be detected, and the concentration of bovine serum albumin in droplets can be estimated. This method is expected to increase the practicality and power of droplet-based microfluidic systems.     

Synthesis, structures, and reactivity of yttrium alkyl and alkynyl complexes with mixed Tp(Me2)/Cp ligands

The structurally characterized Tp(Me2)-supported rare earth metal monoalkyl complex (Tp(Me2))CpYCH(2)Ph(THF) (1) was synthesized via the salt-metathesis reaction of (Tp(Me2))CpYCl(THF) with KCH(2)Ph in THF at room temperature. Treatment of 1 with 1 equiv of PhC≡CH under the same conditions afforded the corresponding alkynyl complex (Tp(Me2))CpYC≡CPh(THF) (2). Complex 1 exhibits high activity toward carbodiimides, isocyanate, isothiocyanate, and CS(2); treatment of 1 with such substrates led to the formation of a series of the corresponding Y-C(benzyl) σ-bond insertion products (Tp(Me2))CpY[(RN)(2)CCH(2)Ph] (R = (i)Pr(3a), Cy(3b), 2,6-(i)Pr-C(6)H(3)(3c)), (Tp(Me2))CpY[SC(CH(2)Ph)NPh] (4), (Tp(Me2))CpY[OC(CH(2)Ph)NPh] (5), and (Tp(Me2))CpY(S(2)CCH(2)Ph) (6) in 40-70% isolated yields. Carbodiimides and isothiocyanate can also insert into the Y-C(alkynyl) σ bond of 2 to yield complexes (Tp(Me2))CpY[(RN)(2)CC≡CPh] (R = (i)Pr(7a), Cy(7b)) and (Tp(Me2))CpY[SC(C≡CPh)NPh] (9). Further investigation results indicated that 1 can effectively catalyze the cross-coupling reactions of phenylacetylene with carbodiimides. However, treatment of o-allylaniline with a catalytic amount of 1 gave only the benzyl abstraction product (Tp(Me2))CpY(NHC(6)H(4)CH(2)CH═CH(2)-o)(THF) (10), without observation of the expected organic hydroamination/cyclization product. All of these new complexes were characterized by elemental analysis and spectroscopic properties, and their solid-state structures were also confirmed by single-crystal X-ray diffraction analysis.     

Polyacrylamide hydrogels with phenylboronic acid moieties for the imprinting of proteins

<正>In this letter,N-acryloyl-3-aminophenylboronic acid(AAPBA) was synthesized and then examined as a new functional monomer for protein imprinting.It was allowed to be copolymerized with acrylamide to produce hemoglobin- or lysozyme-imprinted hydrogels.In template rebinding tests,the imprinted gels showed significant increase in the specific binding with the increase of the AAPBA amounts in the prepolymerization recipes.These results indicate that AAPBA may be a useful functional monomer for its moderate interactions with protein molecules.     

MoS2 nanorods with inner caves through synchronous encapsulation of sulfur for high performance Li–S cathodes

Lithium–sulfur(Li–S)batteries have become one of the most promising candidates for next-generation batteries owing to their high specific capacity,low cost,and environment-friendliness.Many efforts have been made to mitigate the"shuttle effect"through physical adsorption and chemical bonding.MoS2 has been proposed as a cathode material to provide effective anchoring sites for lithium polysulfides(Li PSs),but is still limited by its layer structure.Herein,we designed novel MoS2 nanorods with inner caves based on our previous work,and performed synchronous encapsulation of sulfur during the synthesis process.The outer MoS2 tubular shells physically inhibit the outward diffusion of polysulfide species while the inner particles chemically anchor the polysulfides to prevent shuttling.As the cathode matrix in Li–S batteries,the electrochemical results deliver a high initial discharge capacity of 1213 mAhg^-1 for sulfur at 0.1 C.After cycling at 1 C for 300 cycles,the cells exhibit a capacity decay of only 0.076%per cycle and high average coulombic efficiency over 95%.The tubular MoS2 structure is an innovative and appealing design,which could be regarded as a prospective substrate for the improved performance of Li–S batteries.     

From Intercalation to Alloying Chemistry: Structural Design of Silicon Anodes for the Next Generation of Lithium-ion Batteries

Lithium-ion batteries,first commercialized in 1991,have been thriving for the past 30 years and become an important basis for portable electronics and electric vehicles.However,this first generation of lithium-ion batteries built on the intercalation materials has limited energy density and can not meet the increased demand of various applications.Thus,a transition from intercalation to alloying chemistry for anodes is on call.Silicon,as the most attractive alloying anode material,has been on the research focus for next-generation highenergy density battery.Alloying mechanism benefits silicon a large capacity while brings silicon the challenge of volume expansion.This article discusses the structure design strategies to address the issues of large volume change and interface instability.     

Synthesis and Properties of New-type Troponoid Dithio-Crown Ethers

Troponoiddithio-crownethersareakindofnovelcomPounds.Takeshitaetall-'havereportedthesynthesisandmercurophilicpropertiesofthiskindofcompounds.lnthereportedcomPounds,thetWosulfuratomsareattached,partorall,tothetroponeringdirectly.Whetherthedithio-crownethersstillhaveselectiveandreversiblemercurysaltcaptUringabi1itywhenthetWosulfuratomslinktothebenZylic-mpepositionoftroponeringarousedourinterest.Herein,wewishtoreportthatfromthereactionof3,7-dichloromethyl-5-isopropyl-2-methoxytropone4withbis(mer…     

Photodissociation of Cycloketones by Ultraintense Femtosecond Laser Pulses

ThestudyofphotoionizationandphotodissociationprocessesinducedbyintensefemtosecondlaserpuIses(>lo"W/cm')withpolyatomicmoleculesbecomesofinterestbecausesomenewphenomenahavebeenobserved'-3.Sofar,mostoftheinvestigationsfocusontheexperimentalexplorationofphotoionizationprocesses'-'.Butthephotoionizationmechanismofpolyatomicmoleculesinanintensefslaserfieldisstillambiguous'.,.Incontrasttothephotoionizationprocesses,theunderstandingoffragmentationofmolecularionisevenpoorer.Corkumetal,'.,'reportedthef…     

Synthesis and molecular modeling study of Cu(Ⅱ) complexes derived from 2-(diphenylmethylene)hydrazinecarbothioamide derivatives with cholinesterase inhibitory activities

Thiosemicarbazones of 2-amino-5-chlorobenzophenone and 3-aminobenzophenone（L¹-L⁴） have been synthesized and their Cu（Ⅱ） complexes（1-4） were afforded via coordination with cupric chloride.All these compounds were characterized by UV-vis and IR spectroscopy together with CHN elemental analysis.NMR spectroscopy was also applied to characterize the ligands.In vitro chohnesterase inhibitory assays for the complexes（1-4） showed IC₅₀ values less than 10μmol/L,with complex 1 exhibiting the most activity,IC₅₀=2.15μmol/L and 2.16μmol/L for AChE and BuChE,respectively. Molecular modeling simulation revealed the binding interaction template for complex 1 with the AChE and BuChE receptors.In DPPH assay,the complexes also showed more in vitro antioxidant activities in comparison to their parent ligands.     

Preparation, characterization of hydrophilic and hydrophobic drug in combine loaded chitosan/cyclodextrin nanoparticles and in vitro release study

The compound nanoparticles of chitosan (CS) and cyclodextrin (CD) loading with hydrophilic and hydrophobic drug simultaneously were prepared via the cross-linking method. Methotrexate (MTX) and calcium folinate (CaF) were selected as the model drugs. The prepared nanoparticles were characterized by FT-IR spectroscopy to confirm the cross-linking reaction between CS and cross-linking agent. X-ray diffraction (XRD) was performed to reveal the form of the drug after encapsulation. The average size of nanoparticles ranged from 308.4 ± 15.22 to 369.3 ± 30.01 nm. The nanoparticles formed were spherical in shape with high zeta potentials (higher than +30mV). In vitro release studies in phosphate buffer saline (pH 7.4) showed an initial burst effect and followed by a slow drug release. Cumulative release data were fitted to an empirical equation to compute diffusional exponent (n), which indicated the non-Fickian trend for drug release.