Article
Polymer Science
Xiaoyan Guan, Sheng Wang, Ge Shi, Jie Zhang, Xinhua Wan
Summary: The study investigates the cis-trans isomerization of amides in synthetic macromolecules and its potential to induce helical inversion, mimicking natural protein behavior. The results show that the size of the N-alkyl substituents significantly influences the helical inversion caused by the cis-trans isomerization, with N-methyl groups favoring helical transition and N-propyl groups leading to predominantly cis isomers without inducing helical inversion upon thermal treatment.
Review
Polymer Science
Guanzhao Wu
Summary: Chiral separation by HPLC using a CSP is a reliable method for obtaining pure enantiomers. Helical polyacetylene derivatives show excellent chiral recognition abilities and are promising CSP candidates for HPLC. This review discusses the development of helical polyacetylene derivatives with different chiral pendants and their potential as coated CSPs for enantioseparation in HPLC.
Article
Chemistry, Multidisciplinary
Ayhan Yurtsever, Sandip Das, Tatsuya Nishimura, Rafael Rodriguez, Daisuke Hirose, Kazuki Miyata, Ayumi Sumino, Takeshi Fukuma, Katsuhiro Maeda
Summary: The study visualized the helical structures of poly(diphenylacetylene)s bearing optically active substituents linked through amide bonds and with a helicity memory using atomic force microscopy. The polymers self-assembled into an ordered 2D monolayer on highly oriented pyrolytic graphite upon exposure to solvent vapor, with the helical pitch and handedness (right- and left-handed) directly revealed at molecular resolution for the first time.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Na Liu, Xinyue Zhou, Li Zhou, Zongquan Wu
Summary: A novel diazoacetate monomer was successfully synthesized, leading to the formation of helical polycarbenes with well-defined molecular weights and low polydispersity. These polycarbenes showed high catalytic ability in asymmetric Michael addition reactions, with increased enantioselectivity and diastereoselectivity compared to traditional catalysts. Additionally, the helical polycarbene catalyst can be easily recovered and reused multiple times without significant loss of its selectivity.
Article
Polymer Science
Zhen-Zhen Sun, Yan-Ning Zhang, Hao-Yu Qiu, Xue-Ting Lu, Liang-Xuan Ren, Le-Fei Shen, Wen Li, Afang Zhang
Summary: In this study, a homologous series of dendronized PPAs carrying different dendritic OEG pendants were synthesized, and the effects of molecular topological structures and polymerization solvents on their thermoresponsive behavior and conformation switching were investigated. The results showed that the branching density, peripheral units, and polymerization solvents played decisive roles in modulating the thermoresponsive behavior and helical conformation of the dendronized PPAs.
CHINESE JOURNAL OF POLYMER SCIENCE
(2023)
Article
Polymer Science
Ge Shi, Xiao Dai, Qian Xu, Jun Shen, Xinhua Wan
Summary: The research systematically explored the correlations among the nature, size, and position of the substituent on the phenyl ring with the polymer conformation and enantioseparation performance using NMR, Raman and UV-absorption spectroscopy, polarimetry, circular dichroism, HPLC, and computational simulation. It was found that the strength of the hydrogen bond and pi-pi interactions between enantiomers and CSPs played a remarkable role in enantioseparation.
Article
Polymer Science
Eman Zmaily Dahmash, Dalia Khalil Ali, Hamad S. Alyami, Hussien AbdulKarim, Mohammad H. Alyami, Alhassan H. Aodah
Summary: Thymoquinone (TQ), the main active constituent of Nigella sativa, has shown broad-spectrum antimicrobial, antioxidant, and anti-inflammatory effects. However, its clinical use has been hindered by limited solubility and bioavailability. To overcome these limitations, a targeted delivery system using nanotechnology to deliver TQ to the lungs is needed.
Article
Biochemical Research Methods
Xinyuan Guo, Panpan Shang, Benben Wei, Wenrong Du, Yong Lan, Ligai Bai, Xiaoqiang Qiao, Zhengyue Ma
Summary: This study presents the development of three new chiral stationary phases, immobilized on 3-aminopropyltrimethoxysilane modified silica gel. The enantioselective performance of the stationary phases was evaluated using nine racemic compounds and optimized separation conditions were established. The reproducibility of the stationary phases was also investigated, showing good reproducibility (RSD=0.12%, n=5).
Article
Agriculture, Multidisciplinary
Xuewen Hua, Wenrui Liu, Yan Chen, Jing Ru, Shangjing Guo, Xiaobo Yu, Yanhong Cui, Xinghai Liu, Yucheng Gu, Chenmeng Xue, Yi Liu, Junkang Sui, Guiqing Wang
Summary: New green fungicides developed through structural optimization of natural products can effectively address the low safety and high pathogen resistance issues associated with traditional fungicides. In this study, a series of L-serine-derived pyrazole amide and waltherione alkaloid-derived pyrazole ester derivatives were synthesized based on the pyrazole amide compound h-I-9 with excellent fungicidal activity. Compound II-5 exhibited good inhibition against Physalospora piricola, potentially causing damage to cell membranes and vacuoles and producing blue fluorescence in treated hyphae. Additionally, compounds 1-3 and 1-4 showed potential as succinate dehydrogenase (SDH) inhibitors against Alternaria sp.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2021)
Article
Polymer Science
Burcu Acik, Gokhan Acik, Hamit Erdemi
Summary: A series of environmentally friendly polyurethane films were successfully synthesized by ring-opening polymerization and step-growth polymerization methods. The study found that a higher proportion of epsilon-caprolactone repeating units in the polyurethane backbone could enhance hydrophobicity, thermal and mechanical properties, but also deteriorate degradation behavior. Biodegradation tests revealed that CA-PCL-PUs are more degradable in enzymatic media, indicating great potential for applications in tissue engineering and wound dressing.
EUROPEAN POLYMER JOURNAL
(2021)
Article
Biochemistry & Molecular Biology
Mohammed Khuddus, Manickam Jayakannan
Summary: In this study, a l-amino acid-based amide-functionalized polyester platform was developed for drug delivery in cancer cells. The polyester nanoparticles exhibited excellent encapsulation capabilities and were able to inhibit cancerous cell growth.
Article
Agriculture, Multidisciplinary
Shanqiao Chen, Wei Jiang, Zhidong Sun
Summary: This study introduced LAE as a candidate active ingredient for citrus preservation and provided a theoretical basis for the development of preservation technology for high-value perishable fruit. The results showed that LAE had an inhibitory effect against the predominant spoilage-inducing fungus Penicillium expansum, and it was partially synergistic with natamycin. The application of LAE in preharvest spraying significantly reduced spoilage rate and alleviated pectin loss without extra taste loss. Electron microscopic imaging and intracellular protein levels indicated that LAE increased permeability and decreased cell integrity. LAE also enhanced oxidative stress and antagonized pectinase.
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
(2022)
Article
Biochemistry & Molecular Biology
Lea Kukoc-Modun, Tomislav Kraljevic, Dimitrios Tsikas, Njegomir Radic, Darko Modun
Summary: A new FIA method was developed and validated for the determination of N-acetyl-l-cysteine ethyl ester (NACET), based on the reduction of Cu(II)-ligand complexes with the analyte. The method showed linear calibration curves for NACET with three different ligands, achieving the high demands for accurate determination of NACET in pharmaceutical preparations.
Article
Medicine, General & Internal
B. S. Burlaka, I. F. Bielenichev
Summary: Developing novel medications for delivering active ingredients with systemic absorption and high bioavailability is a challenge in modern pharmaceutical and medical science. Intranasal administration has been recognized as a potential method for improving neuroavailability and therapeutic effect of drugs.
ZAPOROZHYE MEDICAL JOURNAL
(2021)
Article
Polymer Science
Huan Li, Yingying Li, Yudan Wang, Lijia Liu, Hongxing Dong, Chunhong Zhang, Toshifumi Satoh
Summary: In this study, a Lys-BPEA crosslinker was synthesized using primary amines rich in lysine end groups. An antibacterial self-healing hydrogel (PAA/Lys-BPEA) was prepared by introducing polyamine Lys-BPEA into PAA via ionic bonding and electrostatic interaction. The PAA/Lys-BPEA hydrogel exhibited excellent antibacterial and self-healing properties, making it an ideal choice for the design of smart self-healing devices and antibacterial surface coatings.
Article
Polymer Science
Ryohei Sato, Atsuo Utagawa, Koji Fushimi, Feng Li, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin-ichiro Sato, Hiroshi Hirata, Yoshihiro Kikkawa, Takuya Yamamoto
Summary: The redox behaviors of macrocyclic molecules with an entirely pi-conjugated system were investigated in this study. Cyclic P3HT with different degrees of polymerization (DPn) were synthesized, and its unique redox behaviors were compared with linear P3HT. Cyclic P3HT showed a decrease in HOMO level and greater stability during cyclic voltammetry measurement, indicating stronger dicationic properties due to polaron-polaron interactions.
Article
Chemistry, Multidisciplinary
Erika Terada, Takuya Isono, Toshifumi Satoh, Takuya Yamamoto, Toyoji Kakuchi, Shinichiro Sato
Summary: Recently, temperature-responsive polymers tethered to oligooxyethylene side chains terminated with alkyl groups were experimentally investigated. Molecular dynamics simulations were used to study aqueous solutions of poly(glycidyl ether)s with different numbers of oxyethylene units. The thermal responses of chain extensions, hydrogen bond recombination, and water-solvation shells were analyzed. The phase-transition temperature was not directly related to the polymer-chain extensions, but the temperature response of the water-solvation shell around the alkyl group showed a noticeable correlation. The relationship between TCRP and TCLP was found to be affected by polymer-chain fluctuation.
Article
Nanoscience & Nanotechnology
Chun-Kai Chen, Jin-Chieh Ho, Chih-Chien Hung, Wei-Cheng Chen, Toshifumi Satoh, Wen-Chang Chen
Summary: In this study, an environmentally friendly floating-gate electret made entirely from biomass-derived materials was designed for photonic memories. The photosensitive hemin and its derivative protoporphyrin IX (PPIX) were successfully embedded in a polylactic acid (PLA) matrix, affecting the photosensitivity and charge-trapping capacity of the prepared electrets. The device exhibited a memory ratio of up to 2.5 x 10(7) with photo-writing-electrical-erasing characteristics, and sustained memory performance for at least 10(4) s after light removal was observed on a bio-derived dielectric flexible substrate.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Mahmoud M. Abd Elwakil, Ryota Suzuki, Alaa M. Khalifa, Rania M. Elshami, Takuya Isono, Yaser H. A. Elewa, Yusuke Sato, Takashi Nakamura, Toshifumi Satoh, Hideyoshi Harashima
Summary: mRNA lipid nanoparticles (LNPs) have been successfully developed to deliver mRNA to immune cells in the spleen, showing great potential for precision therapies. The design of ligand-free glycidylamine (GA) derivatives containing LNPs (GA-LNPs) with specific characteristics have significantly improved their self-assembly and RNA delivery efficiency. The top-performing estriol-GA05-30 LNPs exhibited strong antitumor activity and promising results in therapeutic and prophylactic cancer models, highlighting the importance of ionizable lipids for extrahepatic RNA delivery.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Minami Ebe, Asuka Soga, Kaiyu Fujiwara, Brian J. Ree, Hironori Marubayashi, Katsumi Hagita, Atsushi Imasaki, Miru Baba, Takuya Yamamoto, Kenji Tajima, Tetsuo Deguchi, Hiroshi Jinnai, Takuya Isono, Toshifumi Satoh
Summary: In this study, the synthesis of macro-rotaxanes consisting of high-molecular-weight axle and wheel components (macro-rotaxanes) was achieved by the topological trapping of multicyclic polydimethylsiloxanes (mc-PDMSs) in silicone networks. mc-PDMSs with more cyclic units and larger ring sizes can be quantitatively trapped in the network as macro-rotaxanes, compared to monocyclic PDMS. The damping performance of a 60 wt % mc-PDMS-blended silicone network was found to be higher than the bare PDMS network, suggesting the potential application of macro-rotaxanes as non-leaching additives for network polymers.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Feng Li, Ryota Suzuki, Tianle Gao, Xiaochao Xia, Takuya Isono, Toshifumi Satoh
Summary: Polymer materials are crucial in shaping modern society. The development of new catalysts, such as alkali metal carboxylates, plays an important role in the continuous advancement of polymer materials. These simple compounds have demonstrated their potential as catalysts in various polymerization reactions.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2023)
Article
Chemistry, Applied
Satoshi Katsuhara, Naoki Sunagawa, Kiyohiko Igarashi, Yutaka Takeuchi, Kenji Takahashi, Takuya Yamamoto, Feng Li, Kenji Tajima, Takuya Isono, Toshifumi Satoh
Summary: This study synthesized cellulose acetate-based TPEs with different degrees of substitution (DS) and investigated the impact of DS on their structure and properties. The results showed that decreasing DS led to the formation of a more ordered microphase-separated structure, improved toughness, suppressed stress relaxation, and enhanced biodegradability potential. This work demonstrates the potential of cellulose acetate-based TPEs as next-generation sustainable materials.
CARBOHYDRATE POLYMERS
(2023)
Article
Chemistry, Physical
Yuanyuan Gu, Lijia Liu, Yudan Wang, Chunhong Zhang, Toshifumi Satoh
Summary: Hierarchical chiral self-assembly of an amphiphilic helical poly(phe-nylacetylene) homopolymer containing bi-valine pendants was achieved by adding a polar solvent into the polymer solution. The influences of solvent components and temperature on the supramolecular chirality and morphologies of ordered nanostructures were investigated. Various morphologies including spheres, beads-string micelles, vesicles, nanorods, flower-like, and blocky nanostructures were obtained. The chiral property endowed by bi-valine pendants in the polyphenylacetylene backbone was transferred and enhanced in high-ordered supramolecular self-assemblies. The increase of polar solvent fraction significantly promoted the aggregation of multi micelles.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Multidisciplinary
Hien Thi Phan, Shoko Furukawa, Koto Imai, Hiroya Tomita, Takuya Isono, Toshifumi Satoh, Ken'ichiro Matsumoto
Summary: Bacterial polyhydroxyalkanoate (PHA) synthase PhaC(AR) and its mutated variants were used to synthesize block copolymers with poly(d-lactate) (PDLA) segments. Beneficial mutations N149D and F314H increased the incorporation of D-lactate (LA) units, resulting in the synthesis of P(3HB)-b-PDLA and P(3HHx)-b-PDLA. This study demonstrates a new method for the synthesis of block copolyesters with isotactic PDLA segments from renewable resources using engineered polyester synthase.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Polymer Science
Yamato Ebii, Yoshinobu Mato, Feng Li, Kenji Tajima, Takuya Yamamoto, Takuya Isono, Toshifumi Satoh
Summary: In this study, multicyclic polystyrene (mc-PS) was successfully synthesized through the cyclopolymerization of alpha,omega-dinorbornenyl end-functionalized PS macromonomers mediated by the Grubbs third-generation catalyst. The number of cyclic units in the obtained mc-PS was controlled by adjusting the macromonomer-to-G3 ratio, with a maximum of 239 units achieved. The developed cyclopolymerization strategy provides a new approach for the synthesis of multicyclic polymers and has significant implications for fundamental studies and material applications.
Article
Chemistry, Multidisciplinary
Yaodong Wang, Yudan Wang, Lijia Liu, Kexiao Sang, Chunhong Zhang, Toshifumi Satoh
Summary: Metal-free catalysts have emerged as an important research focus in catalysis due to the growing concern over heavy metal pollution. In this study, a heterogeneous catalyst, l-Pro-l-Pro-l-Phe-l-Phe-OMe, was synthesized by connecting an aromatic amino acid dipeptide (l-Phe-l-Phe-OMe) with a proline dipeptide (l-Pro-l-Pro) through solid phase synthesis. The catalyst's structure was characterized using SEM, XRD, NMR, and FTIR spectroscopy, with X-ray diffractometry revealing a rod crystal structure. Furthermore, l-Pro-l-Pro-l-Phe-l-Phe-OMe exhibited superior catalytic activity compared to a homogeneous small molecule catalyst (high enantioselectivity, ee > 97%) in heterogeneous asymmetric aldol reactions and demonstrated good recyclability.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Polymer Science
Takuya Isono, Ema Baba, Shunma Tanaka, Ken Miyagi, Takahiro Dazai, Feng Li, Takuya Yamamoto, Kenji Tajima, Toshifumi Satoh
Summary: By direct post-polymerization modification, commercial PS-b-PMMA can be successfully transformed into ordered microphase-separated structures with a periodicity as low as approximately 16 nm. The installation of adamantyl group not only increases incompatibility with the PMMA block, but also improves thermal stability, glass transition temperature, and etching contrast.
Article
Polymer Science
Yaodong Wang, Lijia Liu, Yudan Wang, Kexiao Sang, Chunhong Zhang, Toshifumi Satoh
Summary: An l-phenylalanine dipeptide monomer was cross-linked to form a chiral porous polymer skeleton, which was then modified with l-proline to produce a catalyst with a higher specific surface area. The catalyst exhibited improved catalytic efficiency and selectivity in asymmetric Michael addition and Mannich reactions. The recyclable and cost-effective nature of the catalyst makes it an effective strategy for preparing high-performance asymmetric catalysts.
Article
Polymer Science
Kai Chen, Chun -Yu Chen, Hsin-Lung Chen, Ryoya Komaki, Nao Kawakami, Takuya Isono, Toshifumi Satoh, Du -Yuan Hung, Ying-Ling Liu
Summary: The molecular architecture and configuration of sugar-based block copolymers have significant effects on their self-assembly behavior. In this study, we observed the formation of double gyroid and hexagonal perforated layer structures in monodisperse maltose-solanesol block copolymers with different architectural configurations. The oligomeric nature of the copolymers amplified the role of the configuration prescribed by the substituted positions of the block chains.
