[reaction: see text] Reduction of 4-(haloalkyl)azetidin-2-ones with chloroalane (AlH(2)Cl) afforded new 2-(haloalkyl)azetidines in high yields. The latter compounds proved to be very useful starting materials for rearrangements toward stereospecifically defined five- and six-membered azaheterocycles, such as 3,4-cis-disubstituted pyrrolidines and piperidines. During these reactions, bicyclic azetidinium intermediates were formed which were ring opened by a variety of nucleophiles. Hereby, reactions proceeding via 1-azoniabicyclo[2.2.0]hexanes are reported for the first time.
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http://dx.doi.org/10.1021/ol0530676 | DOI Listing |
J Phys Chem A
January 2025
Laboratoire de Chimie Hétérocyclique, Produits Naturels et Réactivité (LR11SE39), Faculté des Sciences de Monastir, Université de Monastir, Avenue de l'Environnement, Monastir 5019, Tunisie.
The kinetics of the σ-complexation reactions of 3,5-dicyanothiophene with a series of cyclic secondary amines - has been studied in water and acetonitrile at 20 °C. Through the linear free energy relationship (LFER) log = s ( + ), the electrophilicity parameter of 3,5-dicyanothiophene has been determined and then integrated into the electrophilicity scale established by Mayr. Molecular dynamics (MD) simulations have been employed to elucidate the reversal in reactivity order between piperidine and pyrrolidine observed in water.
View Article and Find Full Text PDFCurr Top Med Chem
January 2025
GITAM School of Pharmacy, GITAM Deemed to be University, Rudraram, Patancheru, Sanga Reddy, Telangana-502329, India.
Background: Piperidines are among the essential synthetic fragments for designing drugs and play a significant role in the pharmaceutical industry. The synthesis of newer derivatives by incorporating different amines paves the way for the introduction of novel drug combinations for current cancer treatments.
Method: The new combinations of 1-(4-bromo-2-(pyrrolidine-1-yl) benzyl) piperidine derivatives were synthesized by adding various amino groups.
Acta Crystallogr C Struct Chem
January 2025
Institute of General and Ecological Chemistry, Faculty of Chemistry, Łódź University of Technology, Żeromskiego 116, 90-924 Łódź, Poland.
Three new thiosemicarbazide derivatives are described in terms of synthesis, structure and biological activity. N'-(Morpholine-4-carbonothioyl)-4-(4-phenylpiperazin-1-yl)picolinohydrazonamide 2-methyltetrahydrofuran hemisolvate, 2CHNOS·CHO, 1, determined at 100 K, has orthorhombic (Pca2) symmetry and exhibits disorder. 4-(4-Phenylpiperazin-1-yl)-N'-(piperidine-1-carbonothioyl)picolinohydrazonamide-dimethylformamide-water (1/1/0.
View Article and Find Full Text PDFJ Org Chem
December 2024
College of Pharmacy & Graduate School of Pharmaceutical Sciences, Ewha Womans University, 52 Ewhayeodae-gil, Seodaemun-Gu, Seoul 03760, Republic of Korea.
The concise and efficient total synthesis of (±)-tetraponerine-2 () and (±)-tetraponerine-4 () was achieved in 9% and 14% overall yield, respectively. The key step included the diastereoselective gold(I)-catalyzed intramolecular dehydrative amination of an allylic alcohol-tethered sulfamide to produce the 1,3-diamine moiety. The resulting olefinic side chain was then elaborated by cross-metathesis and cyclized to a five-membered pyrrolidine or a six-membered piperidine ring by intramolecular Mitsunobu -alkylation.
View Article and Find Full Text PDFPLoS One
November 2024
Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Kanagawa, Japan.
Neuroinflammation, a hallmark of neurodegenerative diseases, is associated with neuronal cell loss and cognitive dysfunction. Monoacylglycerol lipase (MAGL) is involved in neuroinflammation in the brain via the degradation of endocannabinoid 2-arachidonoylglycerol to arachidonic acid, a precursor of some eicosanoids; therefore, MAGL inhibitors are expected to have anti-inflammatory effects. We recently developed a reversible, selective, central nervous system penetrant, and orally available MAGL inhibitor, compound 4f.
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