[structure: see text] The parent and dipropyl-substituted anti (1a,b) and syn doublebent (2a,b) [5]phenylenes have been assembled by CpCo-catalyzed double cyclization of regiospecifically constructed appropriate hexaynes. (1)H NMR, NICS, and an X-ray structural analysis of 1a reflect the aromatizing effect of double angular fusion on the central ring of the linear [3]phenylene substructure.
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http://dx.doi.org/10.1021/ol049225v | DOI Listing |
Int J Biol Macromol
January 2025
Henan Key Laboratory of Natural Medicine Innovation and Transformation, Henan University, Kaifeng, Henan 475004, China; State Key Laboratory of Antiviral Drugs Henan University, Henan University, Kaifeng, Henan 475004, China. Electronic address:
Currently, the clinical drugs for Parkinson's disease (PD) only focus on motor symptoms, while non-motor symptoms like depression are usually neglected. Even though, the efficacy of existing neurotherapeutic drugs is extremely poor which is due to the blood brain barrier (BBB). Therefore, a biomimetic polydopamine carbon dots (PDA C-dots) at 2-4 nm was synthesized, while exosomes from macrophages were applied to encapsulate PDA C-dots for improving their BBB-crossing ability and inflammation-targeting effect.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Pharmacy, University of Naples Federico II, 80131 Napoli, Italy.
Thrombin binding aptamer (TBA) is one of the best-known G-quadruplex (G4)-forming aptamers that efficiently binds to thrombin, resulting in anticoagulant effects. TBA also possesses promising antiproliferative properties. As with most therapeutic oligonucleotides, chemical modifications are critical for therapeutic applications, particularly to improve thermodynamic stability, resistance in biological environment, and target affinity.
View Article and Find Full Text PDFMolecules
December 2024
"C. D. Nenitzescu" Institute of Organic and Supramolecular Chemistry, Splaiul Independentei 202B, 060023 Bucharest, Romania.
Azulene-1,3-bis(semicarbazone), , and azulene-1,3-bis(thiosemicarbazone), , were synthesized by the acid-catalyzed condensation reactions of semicarbazide and thiosemicarbazide, respectively, with azulene-1,3-dicarboxaldehyde in stoichiometric amounts. Compounds and were identified by high-resolution mass spectrometry and characterized by IR, H-NMR, C-NMR, and UV-vis spectroscopic techniques. Crystal structure determination of azulene-1,3-bis(thiosemicarbazone) shows that the thiosemicarbazone units exhibit a -closed conformation, with both arms oriented in the same direction and adopting an configuration with respect to the imine linkages.
View Article and Find Full Text PDFMonatsh Chem
December 2023
Institute of Applied Synthetic Chemistry, TU Wien, Vienna, Austria.
Unlabelled: In recent years, sugar alcohols have gained significant attention as organic phase change materials (PCMs) for thermal energy storage due to their comparably high thermal storage densities up to 350 J/g. In a computational study, outstandingly high values of up to ~ 450-500 J/g have been postulated for specific higher-carbon sugar alcohols. These optimized structures feature an even number of carbon atoms in the backbone and a stereochemical configuration in which all hydroxyl groups are in an 1,3--relationship, as found in the natural hexitol d-mannitol.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
New Cornerstone Science Laboratory, State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
The asymmetric Tsuji-Trost reaction has been extensively studied due to its importance in establishing stereogenic centers, often adjacent to an -olefin moiety in organic molecules. The generally preferential formation of chiral -olefin products is believed to result from the thermodynamically more stable -π-allylpalladium intermediate. The rapid associative π-σ-π isomerization makes it challenging to synthesize chiral -olefin products via the transient -π-allylpalladium intermediate.
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