查看更多>>摘要：The development of transition-metal free systems for multi-sites deuteration is important for the preparation of deuterium-labeled drugs and intermediates. We reported that ionic liquid [bmim]PF6 was able to promote highly efficient deuterodeborylation of boronic acids with D2O. The ionic liquid/boronic acid system was successfully applied to the selective H/D exchange at various sp(2)/sp(3) C-H positions. Moreover, unusual nucleophilic behaviors of nitrogen-containing heteroaromatics in ionic liquid were observed. (C) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：A 1,4,2-diazaborole-type heterocycle was obtained via addition of [(alkylamino)methyl]-trifluoroborate to 2H-azirine-2-carboxylate. The molecular structure of the product was confirmed by X-ray crystallog-raphy. The reaction proceeded at ambient temperature without metal catalysts and induced cleavage of the azirine C2-C3 bond without photoirradiation. This product can be regarded as a boron-containing peptidomimetic molecule that has potential applications in medicinal and synthetic chemistry.(c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Enantioselective construction of the central [3.2.1] oxa-bicyclic core of hedyosumins A-C was achieved via an enantioselective Diels-Alder reaction and a platinum(II)-catalyzed 1,3-dipolar [3+2] cycloaddition as key steps, which leads to the asymmetric total synthesis of hedyosumins A-C. (c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Three new sesquiterpenoids, gingerterpenes B-D (1-3), two new diterpenoids, gingerterpenes E-F (4-5), and two known sesquiterpenoids (6-7) were isolated from Zingiberis Rhizoma. The structures of com-pounds (1-5) were determined by their 1D-NMR, 2D-NMR data and mass spectrometry. Their absolute configurations were determined by comparing their experimental and theoretically calculated ECD curve and quantum mechanical (QM) NMR approach. Compounds 2-7 were evaluated their cell viability, anti-apoptosis levels on human normal lung bronchial epithelial cells, which induced by lipopolysaccharide at 10 lM. (c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Although a number of palladium(II) probes have been developed, most of them have small Stokes shifts and lack good subcellular targeting ability. In this paper, a reaction-based probe (DCF-MPYM-Pd) has been designed and synthesized for palladium(II) detection. The probe was constructed by a fluorescein derivative as the fluorophore and an allyl ester group as the recognition group. The probe exhibited fast response time (5 min), high sensitivity and specificity. Importantly, it has a large Stokes shift and lysoso-mal targeting capability. In addition, it was demonstrated that the probe can be used to sense palladium (II) in living cells and can accumulate specifically in lysosomes.(c) 2022 Elsevier Ltd. All rights reserved.
Kumar, YogendraPalluruthiyil, Mary AntonyIniyavan, PethaperumalIla, Hiriyakkanavar...
6页
查看更多>>摘要：An efficient one-pot, three-component synthesis of novel push-pull 1,3-benzodithiol-2-ylidenes, involv-ing reaction of active methylene compounds with CS2 in the presence of NaH as the base, followed by in situ Cu-catalyzed bis-C-S coupling of the resulting dithioate salts with 1-bromo-2-iodobenzenes has been reported. The methodology involves readily available starting materials and tolerates a broad range of functional groups. (C) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Sulfilimines, the aza-analogs of sulfoxides, are valuable building blocks in organic synthesis and serve as important functional groups in medicinal chemistry. Herein we reported an efficient and environmen-tally friendly method of preparing sulfilimines from readily available thioether and sulfonamide as sub-strate. The reaction proceeds via the in-situ produced hypervalent iodine from catalytic simple iodobenzene under electrooxidation conditions. A series of sulfilimines were obtained in moderate to good yields.(c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Histone post-translational modifications (hPTMs) regulate series fundamental cellular processes through the specific recognition of "reader" or "effector" proteins. The chemical probes containing photo-cross -linking groups, especially diazirine group has been developed to capture proteins recognized by hPTMs. However, the construction of diazirine-based photo-reactive amino acids requires multiple syn-thetic steps. Herein, we report the efficient synthesis of a new diazirine-based histone peptide probes through the construction of terminal diazirine via phenyliodonium diacetate (PIDA) mediated transfor-mation. The key building block tert-butyl 3-(3H-diazirin-3-yl)propanoate can be obtained in one step with 90% yield. The synthetic H3K4Me3 photo-cross-linking probe was demonstrated to label H3K4Me3 specific reader in vitro and in cell lysates. (c) 2022 Published by Elsevier Ltd.
查看更多>>摘要：Though the physical blending polymeric preceramic and photosensitive compounds has been proved an easily scaled-up and cost-effective approach to prepare photocurable precursors for most of silicon-based ceramics, there is still scarce of practical photocurable precursor system to SiC ceramic, due to poor com-patibility between polycarbosilane and commercially available photosensitizers. Also, in contrast to intensive research on polymeric precursor, no attention has been paid on development of photosensitive compounds for preceramic polymers. In this work, a series of photosensitive carbosilanes containing Si-C backbone and acrylate group was designed and synthesized, which showed good compatibility with polycarbosilanes. The calculation result on the solubility parameters of the carbosilanes and polycarbosi-lanes well explained their good compatibility. The UV-curing behavior and thermal properties of the pho-tosensitive carbosilanes and their blend systems with polycarbosilanes were also studied. This work provides useful guidelines for selecting and designing photosensitive compounds have good compatibil-ity with preceramic polymers. (c) 2022 Elsevier Ltd. All rights reserved.
查看更多>>摘要：Aryldiazonium ions have been proven to catalyze effective cleavage of aziridines for the installation of varied aryl groups, providing access to a variety of 2-arylphenethylamines. This highly regioselective pro-cess, which can be performed at gram-scale, enjoys operational simplicity, as well as mild and metal-free conditions.(c) 2022 Elsevier Ltd. All rights reserved.
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