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Amino‐single benzene‐based fluorophores (SBBFs) are representative small‐size fluorescent dyes that have an electron push‐pull structure within the benzene core. In this work, a new library of amino‐SBBFs, which have trifluoroacetyl moiety at the electron‐pushing amine group (named SBBF‐TFA), featuring a variety of methylamines, dimethylamines, as well as acetyl. To explore the SBBF‐TFA library, we conducted (i) library synthesis, (ii) assessment of various photophysical properties in nine different types of organic/aqueous solvents, and (iii) evaluation of cytotoxicity in the HeLa cell line. We believe that our findings provide valuable insights for advancing novel small‐molecule fluorescent probes and materials with diverse applications across pharmacochemical fields. [ABSTRACT FROM AUTHOR]

We investigated the off‐target binding of amyloid‐beta (Aβ) target [18F]florapronol ([18F]FC119S) using postmortem Alzheimer's disease (AD) brain tissue, compared with a known Aβ target imaging agent, [125I]TZDM and tau targeting [125I]MK as positive and negative controls, respectively. Off‐target binding of monoamine oxidase‐A and ‐B (MAO‐A and ‐B) was screened for FC119S and Pittsburgh compound B (PiB). Autoradiography (ARG) was performed to screen the Aβ‐binding potential using human AD postmortem brain tissue sections. Colocalization was quantitatively analyzed by using image analysis software. Pathological analysis was performed for screening of specific binding of amyloid‐beta and phospho‐tau. Amyloid‐beta targeting [18F]FC119S and [125I]TZDM tracers were showed a similar binding pattern in ARG, but [125I]MK was showed a different binding patterns. In the blocking experiment, [18F]FC119S binding was effectively blocked by a cold TZDM compound. FC119S and PiB were not showed specific binding with MAO‐A and MAO‐B. The autoradiographic binding pattern was positively correlated with the Aβ expression. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), which are porous inorganic–organic hybrid materials, act as versatile catalyst platforms for various organic transformations. In particular, the aerobic oxidation of alcohols to the corresponding aldehydes (or ketones) has been extensively studied using various MOFs and their analogs. In this account, we summarize the performance of MOF‐based catalysts for the aerobic oxidation of alcohols based on the position of the catalytic species and the type of functionalization. Moreover, recent advances in MOF‐based catalysts for aerobic oxidation are discussed in terms of catalytic efficiency and substrate size discrimination. [ABSTRACT FROM AUTHOR]

Herein, to elucidate the effect of substituent electronic properties on the photophysical properties of indium‐based organometallic luminophores, we prepare a series of indium complexes (1–5) with salen ligands bridged by an electron‐withdrawing 4,5‐dichlorophenylene (Cl2Ph) unit. The structures of all the complexes are fully confirmed by 1H and 13C NMR spectroscopy as well as elemental analysis. In particular, the molecular structure of 3, confirmed by X‐ray crystallography, is monomeric and the central indium atom adopts a square‐pyramidal geometry. The UV/Vis and fluorescence spectra of 1–5 show typically salen‐centered intramolecular charge transfer transitions with gradual bathochromic shifts as the electron‐donating ability of the substituents increases. This feature is further supported by electrochimical studies. Furthermore, the lowest unoccupied molecular orbital energy levels of 1–5 are considerably lower (approximately −3.70 eV) than those of salen‐based indium complexes with other aryl‐bridging units owing to the reduced electron‐donating effect of the (Cl2Ph)salen group. [ABSTRACT FROM AUTHOR]

Lubiprostone (LPT), a novel laxative, is commercially available as a soft gelatin capsule with oily ingredient, complementing its poor water‐solubility and oxygen‐labile property. In the present study, in order to address drawbacks associated with soft capsule formulations such as difficulty in process control or high production costs, conversion of the drug‐loaded oil solution into powder dosage form was attempted using several oily ingredients and porous solid carriers. Drug solubilization in medium chain triglycerides (MCT) drastically improved the drug stability compared to that in powder or other oily ingredients, exhibiting over 95% of the drug remaining after 5 days of storage at 60 °C. However, conversion of drug‐loaded MCT into a free‐flowing powder using porous carriers markedly deteriorated drug stability. Although the drug stability in the solidified formulations prepared using Avicel PH 102 or Aerosil 200 were relatively higher than those prepared using metallic adsorbents (Florite, DCP A/T, and Neusilin US2), they were less stable than in the intact oil solution under stress and accelerated condition. This implied that the decreased thickness of the oily barrier in the solidified formula failed to inhibit the exposure of the labile compound to oxygen and/or moisture, thereby accelerating drug degradation. In vitro drug release from the adsorbent progressed rapidly, providing complete drug release within 15 min, under sink condition. This study suggests that the kind of oily vehicle and the thickness of the barrier are important factors for ensuring the stability of LPT, an oxygen‐labile compound, and additional pharmaceutical approaches are required for the construction of stable solid preparations. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (NIBs) are promising alternatives to lithium‐ion batteries for large‐scale energy applications such as energy storage systems, owing to the earth‐abundance and low cost of sodium resources. Among layered oxide cathode materials for NIBs, O3‐type NaCrO2 has attracted considerable attention owing to its electrochemically active Cr3+/4+, which is unlike that of LiCrO2, and potential for carbon coating with a high thermal stability. In this study, we propose a new facile and eco‐friendly method for applying nitrogen‐doped carbon to NaCrO2 using coffee waste as a carbon source. The synthesized O3‐type NaCrO2/coffee waste–derived N‐doped carbon composite exhibits an outstanding electrochemical performance as an NIB cathode material. The sodium/composite cell achieved a 73.7% capacity retention after 500 charge/discharge cycles and an approximate 50% discharge capacity during 43 s of charge. The results demonstrate the potential use of coffee waste for battery materials with improved electrochemical performances. [ABSTRACT FROM AUTHOR]

Eukaryotic expression systems are used widely and have the advantages of protein processing, proteolytic cleavage, disulfide bond formation, and posttranslational modification in contrast to the prokaryotic expression system. In the present study, peptide gene (olive flounder beta‐defensin or hepcidin) was inserted into the vector of pPIC9K, which involved the secretion signal and promoter AOX1. The colonies with high copy numbers of the target gene for high‐level expression were selected by G418. Approximately 30 mg/L for beta‐defensin and 25 mg/L for hepcidin was obtained from the culture medium supernatant. An ammonium sulfate salting‐out method was used for purification; this one‐step purification simplified the procedures, and the purification effect was good in terms of the purity and yield. The proteins from yeast itself could be isolated easily using the ammonium sulfate salting‐out method. [ABSTRACT FROM AUTHOR]

A kinetic study on nucleophilic substitution reactions of 4-pyridyl benzoate ( 2a) and O-4-pyridyl thionobenzoate ( 2b) with a series of cyclic secondary amines in acetonitrile at 25.0°C is reported. Plots of pseudo-first-order rate constant ( kobsd) vs. [amine] are linear and pass through the origin for the reactions of 2a but curve upward for those of 2b. The upward curvature observed for the reactions of 2b is typical for reactions that proceed through a stepwise mechanism with a zwitterionic intermediate T±, which decomposes to the products via uncatalyzed and catalyzed routes competitively. The reaction of 2a has been suggested to proceed through a stepwise mechanism with T±, in which expulsion of the leaving group occurs in the rate-determining step on the basis of a linear Brønsted-type plot with βnuc = 0.77. The catalyzed reaction of 2b from T± has been proposed to proceed through a concerted mechanism with a six-membered cyclic transition state rather than via a stepwise pathway with an anionic intermediate T−. Factors influencing reactivity and reaction mechanism are discussed in detail. [ABSTRACT FROM AUTHOR]