聚合条件对聚甲基丙烯酸盐体系ER效应的影响

用反相乳液聚合直接合成了具有高电流变（ＥＲ）活性的聚甲基丙烯酸盐（ＳＰＭＡＡ）的悬液。研究了影响ＥＲ效应的因素，结果阐明了该体系中的水分在ＥＲ效应中的作用。     

Effect of Poly(methacrylic acid) on the Cytokine Level in an In Vivo Tumor Model

Cancer is a leading cause of mortality globally. Despite remarkable improvements in cancer-treatment approaches, disease recurrence and progression remain major obstacles to therapy. While chemotherapy is still a first-line treatment for a variety of cancers, the focus has shifted to the development and application of new approaches to therapy. Nevertheless, the relationship between immune response, neoplastic diseases and treatment efficiency is not fully understood. Therefore, the aim of the study was to investigate the immunopharmacological effects of methacrylic acid homopolymer in an in vivo tumor model. Materials and methods: Monomeric methacrylic acid was used to synthesize polymers. Methacrylic acid was polymerized in dioxane in the presence of 4-Cyano-4-[(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoic acid. To study the molecular weight characteristics of PMAA by GPC, carboxyl groups were preliminarily methylated with diazomethane. An experimental cancer model was obtained by grafting RMK1 breast cancer cells. The serum levels of IL-6, IL-10, IL-17, transforming growth factor β1 (TGF-β1), and tumor necrosis factor α (TNF-α) were measured by ELISA. Results: The effect of PMAA on the serum concentrations of several cytokines was studied upon its single administration to laboratory animals in early neoplastic process. The IL-6, IL-17 and TGF-β1 concentrations were found to change significantly and reach the level observed in intact rats. The IL-10 concentration tended to normalize. Conclusion: The positive results obtained are the basis for further studies on the effect of methacrylic-acid polymers with different molecular-weight characteristics on the neoplastic process.     

Multifunctional Cationic PeptoStars as siRNA Carrier: Influence of Architecture and Histidine Modification on Knockdown Potential

RNA interference provides enormous potential for the treatment of several diseases, including cancer. Nevertheless, successful therapies based on siRNA require overcoming various challenges, such as poor pharmacokinetic characteristics of the small RNA molecule and inefficient cytosolic accumulation. In this respect, the development of functional siRNA carrier systems is a major task in biomedical research. To provide such a desired system, the synthesis of 3‐arm and 6‐arm PeptoStars is aimed for. The different branched polypept(o)idic architectures share a stealth‐like polysarcosine corona for efficient shielding and a multifunctional polylysine core, which can be independently varied in size and functionality for siRNA complexation‐, transport and intra cellular release. The special feature of star‐like polypept(o)ides is in their uniform small size (<20 nm) and a core–shell structure, which implies a high stability and stealth‐like properties and thus, they may combine long circulation times and a deep penetration of cancerous tissue. Initial toxicity and complement studies demonstrate well tolerated cationic PeptoStars with high complexation capability toward siRNA (N/P ratio up to 3:1), which can lead to potent RNAi for optimized systems. Here, the synthetic development of 3‐arm and 6‐arm polypept(o)idic star polymers, their modification with endosomolytic moieties, and first in vitro insights on RNA interference are reported on.     

Sugar‐fiber Imprinting to Generate Microgrooves on Polymeric Film Surfaces for Contact Guidance of Cells

Anisotropic surface topography is known to induce the contact guidance of cells, and facile and biocompatible approaches of the physical modification of the pertinent matrix surfaces are thus meaningful for biomaterials. Herein, we put forward a sugar‐fiber imprinting technique to generate microgrooves on hydrophobic polymers demonstrated by the poly(lactic‐co‐glycolic acid) (PLGA) films. Microgrooves were conveniently generated after removing sugar fibers simply by water. The resulting locally anisotropic microgrooves were confirmed to elongate the cells cultured on the surface.     

以樟脑酸及咪唑基化合物为配体的锌配合物的合成、晶体结构及荧光性质

以硝酸锌、樟脑酸(H2CAM)和1,2-二咪唑基二甲苯(obix)或4,4′-二咪唑基二甲联苯(bimb)为原料,在水热条件下得到2个结构不同的配位聚合物[Zn(obix)(CAM)]n(1)和[Zn(bimb)(CAM)]n(2)。对它们进行了元素分析、红外光谱和热重等分析,并利用X-射线洐射测定了它们的单晶结构。配合物1中2个锌离子通过2个obix配体桥连成一个24元大环,它再通过CAM配体连接成一维管状结构,而配合物2中锌离子通过两种配体桥连成二维层状结构。结果说明了辅助配体在配合物组装过程中起着非常重要的作用。此外还研究了它们的荧光性质。     

Configurational Simulations and Theoretical Calculations of Molecularly Imprinted Polymers of Histamine and 2‐(Trifluoromethyl)acrylic Acid Based on Computational Chemistry

In this article, we provide a theoretical discussion on the interactions between a template molecule and functional monomer(s) in the preparation of molecularly imprinted polymers (MIPs ). Density functional theory (DFT ) was used to compute the 3D structures, natural bond orbital, and binding energy in the template–monomer(s) complexes. Histamine (HA ) and 2‐(trifluoromethyl)acrylic acid (TFMAA ) were, respectively, selected as the template and the monomer. The computational process was performed according to B3LYP method with 6‐311 + (d,p) basis set under the different HA–TFMAA ratios from 1:1 to 1:10. The computational results show that the HA–TFMAA complex at the ratio of 1:5 yields no consequence. Furthermore, the HA–TFMAA complex at the ratio of 1:5 allowed the minimum binding energy and the steadiest condition, with four hydrogen bonds. Configurational simulations and theoretical calculations of the template–monomer complex can be used as an appropriate guiding tool for manufacturing MIPs with high specificity and selectivity, thereby avoiding repeated experiments and wastage of substantial time and investment.     

Lewis Acid‐Induced N‐Methyleneamines as Initiators in the Synthesis of Secondary Amine‐Terminated Polymers

Summary: The cationic polymerization of poly(tert‐butyl vinyl ether) using N‐methyleneamine equivalents derived from a Lewis acid/1,3,5‐trimethylhexahydro‐1,3,5‐triazine (TMTA) co‐initiating system is reported. The resulting polymers possessed secondary amine functionality at the chain terminus, verified by derivatization with 4‐chloro‐7‐nitrobenzo‐2‐oxa‐1,3‐diazole (NBD‐Cl) and subsequent analysis with GPC‐UV (470 nm) and ¹H NMR.

Use of N‐methyleneamine equivalents lacking aryl substituents to afford amine‐terminated poly(tert‐butyl vinyl ether).     

基于6-(3，5-二羧基苯基)烟酸金属有机配位聚合物的构筑及其荧光识别性能

利用混合配体设计、合成了2种新颖的金属有机配位聚合物：[Cd（HDCPN）（1,4-bib）_0.5（H₂O）₂]_n（1）和{[Zn（HDCPN）（1,2bimb）]·H₂O}_n（2）（H₃DCPN=6-（3,5-二羧基苯基）烟酸,1,4-bib=1,4-二（1-咪唑基）苯,1,2-bimb=1,2-二（咪唑-1-基甲基）苯）,并通过单晶X射线衍射、红外光谱（IR）、热重分析（TG）和粉末衍射对配合物1和2进行结构表征。结构分析表明1和2都显示一维链结构,并通过π…π作用堆积成三维网络空间结构。进一步研究了配合物1和2的荧光性能及1在水溶液中对阳离子和阴离子的识别。荧光检测显示,配合物1在水溶液中高灵敏识别Fe³⁺、Cr₂O₇^2-和CrO₄^2-离子。同时研究了配合物1对Fe³⁺、Cr₂O₇^2-和CrO₄^2-的荧光猝灭机理。     

Polymeric Nanoformulation of Zoledronic Acid Rescues Osteoblasts from the Harmful Effect of its Native Form: An In Vitro Investigation of Cytotoxic Potential on Osteoblasts and Osteosarcoma Cells

Osteosarcoma (OS) is a malignant tumor, fatal for pediatric patients who do not respond to chemotherapy, alternative therapies and drugs can provide better outcomes. Zoledronic acid (Zol) belonging to the class of bisphosphonates (BPs) has a direct antitumor ability to prevent Ras GTPases modification and stimulate apoptosis. Despite advances in maintaining balance in skeletal events and direct anticancer properties, Zol causes cytotoxicity to normal healthy pre-osteoblast cells, hampering mineralization and differentiation. The study reports the preparation and evaluation of a nanoformulation that can diminish the existing drawbacks of native Zol. The cytotoxic effect is evaluated on bone cancer cells and healthy bone cells with three different cell lines namely, K7M2 (mouse OS cell line), SaOS2 (human OS cell line), and MC3T3E1 (healthy cell counterpart). It is observed that Zol nanoformulation is uptaken more (95%) in K7M2 whereas in MC3T3E1, the percent population internalizing nanoparticles (NPs) is 45%. Zol has a sustained release of 15% after 96 h from the NP which leads to a rescuing effect on the normal pre-osteoblast cells. In conclusion, it can be stated that Zol nanoformulation can be used as a good platform for a sustained release system with minimum side effects to normal bone cells.     

Comparison of Fractionation Methods for the Characterisation of Short Chain Branching as a Function of Molecular Weight in Ethylene 1-Olefin Copolymers

Summary: Rapid and automated analysis of polyolefins is becoming essential for product development in industry. Quantifying short chain branching in ethylene 1-olefin copolymers is common practice. Several different methods are available to perform this type of analysis. Preparative fractionation followed by subsequent analysis of the fraction by SEC and NMR, SEC-FTIR and SEC-IR were studied towards their applicability in polyolefin research and product development environment. The method of choice is defined by prerequisites such as accuracy, labour and time demands but also in versatility and practicability. The most accurate method is limited in terms of sample throughput and the most practical method is limited towards resolution of very low branching. SEC-FTIR is capable to measure even heterogeneous low branched samples like bimodal high density polyethylene in rapid and satisfactory matter.     

Synthesis,Characterization, and Photoluminescence Properties of Silver(I) Metal‐Organic Polymers with Nanochannels Based on 2‐Sulfoterephthalic Acid and Di(pyridin‐2‐yl)amine Ligands

Two new silver(I) 3D coordination polymers, namely [Ag₃(2‐stp)(dpa)]_n ( 1 ) and {[Ag₂(2‐stp)(H₂O)]?Hdpa}_n ( 2 ) (2‐NaH₂stp=sodium 2,5‐dicarboxysulfonate, dpa=di(pyridine‐2‐yl)amine) were synthesized. The complexes were characterized by elemental analysis, FT‐IR spectra, thermogravimetric analyses (TGA), and single‐crystal X‐ray diffraction. In complex 1 , three neighboring Ag ions are bridged by N‐ and O‐atom, forming a 3D coordination network. The molecular structure of 2 is cation? anion species, forming 3D host? guest supramolecular network with the [Hdpa]⁺ cations encapsulated in the nanochannels. The photoluminescence properties of the complexes were also investigated in the solid state at room temperature.     

基于4-(1-咪唑基)苯甲酸配体构筑的一个单一配体和两个混和配体配位聚合物的结构与性质

以4-(1-咪唑基)-苯甲酸(HIBA)为配体,与Cu(NO_3)2·6H_2O和Cd(Ac)_2·2H_2O在加入或不加入5-硝基间苯二甲酸(H_2NPA)的情况下,通过水热法得到了3个新的配位聚合物,分别为{[Cu(IBA)_2]·DMF}n(1)、{[Cd(IBA)2(H_2O)]·3H_2O}n(2)和[Cd_3(IBA)_2(NPA)_2]n(3)。配合物1和2分别为4重和3重穿插的具有金刚石拓扑网络的三维框架结构,配合物3是由混合配体形成的基于一维Cd-羧基次级构筑基元的三维框架结构,其一维构筑基元由Cd髤离子通过IBA-和NPA2-配体同时桥联形成的。此外,还表征了这些化合物的晶相纯度以及配合物2和3的荧光性质。     

Discovery of Novel 2,4-Dianilinopyrimidine Derivatives Containing 4-(Morpholinomethyl)phenyl and N-Substituted Benzamides as Potential FAK Inhibitors and Anticancer Agents

Focal adhesion kinase (FAK) is responsible for the development and progression of various malignancies. With the aim to explore novel FAK inhibitors as anticancer agents, a series of 2,4-dianilinopyrimidine derivatives 8a–8i and 9a–9g containing 4-(morpholinomethyl)phenyl and N-substituted benzamides have been designed and synthesized. Among them, compound 8a displayed potent anti-FAK activity (IC₅₀ = 0.047 ± 0.006 μM) and selective antiproliferative effects against H1975 (IC₅₀ = 0.044 ± 0.011 μM) and A431 cells (IC₅₀ = 0.119 ± 0.036 μM). Furthermore, compound 8a also induced apoptosis in a dose-dependent manner, arresting the cells in S/G2 phase and inhibiting the migration of H1975 cells, all of which were superior to those of TAE226. The docking analysis of compound 8a was performed to elucidate its possible binding modes with FAK. These results established 8a as our lead compound to be further investigated as a potential FAK inhibitor and anticancer agent.     

Synthesis,Crystal Structures,and Fluorescent Properties of Two ZnII/CdII Coordination Polymers Constructed from Isomeric Ligands

The d¹⁰ coordination polymers (CPs), [Zn(L₁)(OH)]_n ( 1 ) and [Cd(L₂)₂]_n ( 2 ) were obtained from isomeric ligands 3‐(6‐aminpyridinium‐3‐yl) benzoic acid (L₁) and 4‐(6‐aminpyridinium‐3‐yl) benzoic acid (L₂), and characterized by elemental analyses, IR spectroscopy, single‐crystal and powder X‐ray diffraction. In compound 1 , a spiral chain structure connected by μ₂‐OH^– and the Zn^II ions, which are further linked by the L₁ ligands to give atwo‐dimensional layered structure. Classical hydrogen‐bonding interactions (O ··· H–N) between adjacent layers result in three‐dimensional supramolecular structure. Compound 2 features a three‐dimensional framework formed by linking [Cd₂(COO)₂] clusters in a bcu net. Thermal stabilities and fluorescent properties of 1 and 2 were also investigated.     

Synthesis,Characterization, and Luminescence of Two New Zinc(II) Coordination Polymers Constructed by 5‐(4‐Carboxybenzyloxy)Isophthalic Acid Ligand

Two coordination polymers, namely Zn(HL)(4,4′‐bpy)_1.5 ( 1 ), [Zn₃(L)₂(BIMB)₂] · 5H₂O ( 2 ) [H₃L = 5‐(4‐carboxybenzyloxy)isophthalic acid, 4,4′‐bpy = 4,4′‐bipyridine, BIMB = 1,4‐bis(1H‐imidazol‐1‐yl)benzene] were synthesized under hydrothermal conditions. Their structures are determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric (TG) analyses. Complex 1 features a 2D 4‐connected network. Complex 2 is a 3D twofold interpenetrating (3,4,6)‐connected net. In addition, the luminescent properties for 1 and 2 were studied in the solid state at room temperature.     

Molecular weight effect on the complexation of poly(methacrylic acid) and poly(ethylene oxide) as studied by high-resolution solid-state C NMR spectroscopy

Complexes of poly(methacrylic acid) (PMAA) and poly(ethylene oxide) (PEO) with different PEO molecular weight were studied by solid-state high-resolution ¹³C NMR spectroscopy, with the emphasis on the PEO molecular weight effect on inter-polymer interaction, morphology and molecular motion. It is found that the crystalline phase of PEO is completely destroyed in the complex. The results of ¹H transverse relaxation times and ¹³C spin-lattice relaxation times indicate that the chain mobility of both PEO and PMAA are greatly restricted by inter-molecular hydrogen-bonding interactions, especially when the molecular weight of PEO is 1500. The bulk structures of the complexes are found to be closely dependent on the molecular weight of PEO. The fraction of “free” PEO segments without forming hydrogen-bonds with PMAA increases with increasing PEO molecular weight.     

Optical Properties and Photopolymerization of Liquid Crystalline (Acetyl) (Ethyl) Cellulose/Acrylic Acid System

The structure and properties of a chiral nematic phase, which reflects one hand of circularly polarized light in a narrow region of wavelength, of fully acetylated (ethyl) cellulose [(acetyl) (ethyl) cellulose, AEC] in acrylic acid (AA) were studied in comparison with (ethyl) cellulose (EC). AEC mesophase formed right-handed chiral nematic structure while EC formed left-handed one. AEC mesophase showed higher birefringence and reflection intensity. The relationship between the reflection wavelength and the polymer concentration was negatively correlated for both AEC and EC mesophases. The relationship between the reflection wavelength and the molecular weight was also negative for AEC mesophase whereas positive for EC mesophase. AEC mesophase was solidified by photopolymerization of AA moiety. It was revealed that the optical properties of AEC mesophase could be preserved by photopolymerization, since the resulting solid material reflects selectively one hand of circularly polarized light.     

Ultrasound Assisted Synthesis and In Silico Modelling of 1,2,4-Triazole Coupled Acetamide Derivatives of 2-(4-Isobutyl phenyl)propanoic acid as Potential Anticancer Agents

The development of an economical method for the synthesis of biologically active compounds was the major goal of this research. In the present study, we have reported the ultrasound-radiation-assisted synthesis of a series of novel N-substituted 1,2,4-triazole-2-thiol derivatives. The target compounds 6a–f were efficiently synthesized in significant yields (75–89%) by coupling 1,2,4-triazole of 2-(4-isobutylphenyl) propanoic acid 1 with different electrophiles using ultrasound radiation under different temperatures. The sonication process accelerated the rate of the reaction as well as yielded all derivatives compared to conventional methods. All derivatives were confirmed by spectroscopic (FTIR, ¹HNMR, ¹³CNMR, HRMS) and physiochemical methods. All derivatives were further screened for their anticancer effects against the HepG2 cell line. Compound 6d containing two electron-donating methyl moieties demonstrated the most significant anti-proliferative activity with an IC₅₀ value of 13.004 µg/mL, while compound 6e showed the lowest potency with an IC₅₀ value of 28.399 µg/mL. The order of anticancer activity was found to be: 6d > 6b > 6f > 6a > 6c > 6e, respectively. The in silico modelling of all derivatives was performed against five different protein targets and the results were consistent with the biological activities. Ligand 6d showed the best binding affinity with the Protein Kinase B (Akt) pocket with the lowest ∆G value of −176.152 kcal/mol. Compound 6d has been identified as a promising candidate for treatment of liver cancer.