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91.
Haeun Song Yoonyoung Kim Inkyu Kim Young‐Kwan Kim Sunbum Kwon Kyungtae Kang 《化学:亚洲杂志》2020,15(1):91-97
The properties of eumelanin‐like particles (EMPs) and pheomelanin‐like particles (PMPs) in regulating the process of amyloid formation of amyloid‐beta 42 (Aβ42) were examined. EMPs and PMPs are effective both in interfering with amyloid aggregation of Aβ42 and in remodeling matured Αβ42 fibers. The results suggest that some (but not all) molecular species consisting of melanin‐like particles (MPs) are responsible for their inhibiting property toward amyloid formation, and the influence is likely manifested by long‐range interactions. Incubating preformed Aβ42 fibers with catechols or MPs leads to the formation of mesh‐like, interconnected Aβ42 fibers encapsulated with melanin‐like material. MPs are kinetically more effective than catechol monomers in this process, and a detailed investigation reveals that 4,5‐dihydroxyindole, a major intermediate in the formation of melanin‐like species, and its derivatives are mainly responsible for remodeling amyloid fibers. 相似文献
92.
Dr. Kwan Yin Cheung Prof. Yasutomo Segawa Prof. Kenichiro Itami 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(65):14791-14801
The development of carbon nanobelts and related belt-shaped polycyclic aromatic hydrocarbons has gained momentum in recent years. This Minireview focuses on the synthetic strategies used in constructing these aesthetically appealing molecular nanocarbons. Examples of carbon nanobelts and related belt-shaped polycyclic aromatic hydrocarbons reported in recent years as well as some representative synthetic attempts in earlier times are discussed. 相似文献
93.
94.
Tamil Selvi Gopal Soon Kwan Jeong Tahani A. Alrebdi Saravanan Pandiaraj Abdullah Alodhayb Muthumareeswaran Muthuramamoorthy 《Materials Today Chemistry》2022
A recently discovered 2D transition titanium metal carbides also called as MXenes (Ti3C2Tx)-based nanocomposite was prepared with Cu2O through wet precipitation technique, and these materials were further developed as the electrode for sensing glucose by chronoamperometry technique. The prepared MXene-Cu2O (Ti3C2Tx-Cu2O) nanocomposite was characterized by XRD, FTIR, UV–Vis spectroscopy, FE-SEM, EDAX, and Raman spectroscopy. Morphological studies of the composites revealed that the micro-octahedral shape of Cu2O is distributed on the surface of MXene with size larger than bare Cu2O. Further, the prepared composite material was fabricated as a sensing probe, and the electrochemical activities were examined by cyclic voltammetric analysis (CV) and chronoamperometric (CA) methods. From the CV and CA investigation, the current response was higher for the composite than the bare material (Cu2O & MXene) in the presence of glucose. The amperometric investigation of MXene-Cu2O composite for the detection of glucose shows a broad linear range (0.01–30 mM) with a sensitivity of 11.061/μAmM cm?2 and a detection limit of 2.83 μM. Further, the fabricated sensor exhibits good selectivity with interfering species like NaCl, fructose, sucrose, urea, ascorbic acid, lactose, short response time, stability, good reproducibility, and compatibility with human serum sample. From the investigation, the prepared MXene-Cu2O composite is a good candidate for the direct detection of glucose molecules and is also well suitable for clinical diagnosis. 相似文献
95.
96.
Inside Back Cover: Selective Inhibition of Lysine‐Specific Demethylase 5A (KDM5A) Using a Rhodium(III) Complex for Triple‐Negative Breast Cancer Therapy (Angew. Chem. Int. Ed. 40/2018) 下载免费PDF全文
Guan‐Jun Yang Wanhe Wang Dr. Simon Wing Fai Mok Chun Wu Betty Yuen Kwan Law Dr. Xiang‐Min Miao Ke‐Jia Wu Dr. Hai‐Jing Zhong Prof. Dr. Chun‐Yuen Wong Prof. Dr. Vincent Kam Wai Wong Prof. Dr. Dik‐Lung Ma Prof. Dr. Chung‐Hang Leung 《Angewandte Chemie (International ed. in English)》2018,57(40):13349-13349
97.
A collection of the cyanobacterium Lyngbya confervoides off Grassy Key in Florida yielded grassypeptolide (1), a 31-membered macrocyclic depsipeptide with unusually high D-amino acid content, two thiazolines, and one beta-amino acid. We report the rigorous 3D structure determination and conformational analysis in solution and solid state by NMR, MS, X-ray crystallography, chemical degradation, and molecular modeling involving distance geometry and restrained molecular dynamics. Grassypeptolide (1) inhibited cancer cell growth with IC50 values from 1.0 to 4.2 microM. 相似文献
98.
Qin B Chen X Fang X Shu Y Yip YK Yan Y Pan S Ong WQ Ren C Su H Zeng H 《Organic letters》2008,10(22):5127-5130
Introduction of a continuous hydrogen-bonding network suppressed the conformational flexibility of an oligomeric backbone. Cyclization of a rigidified, suitably sized oligomer led to a circular aromatic pentamer. Its crystal structure determined by X-ray crystallography reveals a pseudo five-fold symmetric planarity in the solid state, which is quite unusual among all the previously described shape-persistent macrocycles and synthetic foldamers with biased conformations enforced by noncovalent forces. 相似文献
99.
Choi MG Ryu de H Jeon HL Cha S Cho J Joo HH Hong KS Lee C Ahn S Chang SK 《Organic letters》2008,10(17):3717-3720
The chemodosimetric behavior of dichlorofluorescein derivatives toward Hg(2+) ions was investigated. Simple chemodosimetric systems showed selective and efficient signaling behaviors toward micromolar concentrations of Hg(2+) ions over other common interfering metal ions in an aqueous environment. The signaling mechanism is selective mercuration of the 4',5'-position of the xanthene moiety, which results in efficient chromogenic and fluorogenic signaling of Hg(2+) ions in aqueous environment. 相似文献
100.
Microfabricated HZSM-5 micromembranes were successfully employed as a proton-exchange membrane in a micro fuel cell and the energy generation is strongly dependent on the Al-content of the HZSM-5. 相似文献