Inulin ethers carrying primary amino groups have many potential applications. O-(Aminopropyl)inulin is obtained from O-(cyanoethyl)inulin by reduction of the nitrile groups. Heterogeneously catalyzed hydrogenation using Raney-cobalt as the catalyst resulted in only partial conversion of the O-cyanoethyl into O-aminopropyl groups. Complete conversion of the nitriles to primary amines was achieved by a homogeneous reduction with an excess of sodium borohydride and cobaltous chloride or with metals in liquid ammonia-methanol. Optimal results were obtained with the latter method; 83% of the substituents were converted into primary amines and 17% were lost by dealkylation.
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http://dx.doi.org/10.1016/s0008-6215(98)00174-8 | DOI Listing |
Pediatr Pulmonol
January 2025
Hôpital Femme Mère Enfant, Hospices Civils de Lyon, 59 Boulevard Pinel, Lyon, France.
Background: New CFTR Modulator triple therapy Elexacaftor-Ivacaftor-Tezacaftor (ETI) prove efficacy in pulmonary outcomes. However, its impact on nasal sinus symptoms in children has not been specifically studied. The aim of this study is to evaluate the impact of this therapy on nasal sinus symptomatology in children aged 6-12 years.
View Article and Find Full Text PDFACS Omega
January 2025
Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan.
Various symmetric and asymmetric imines were synthesized using the novel amine oxidase, obtained as variants of d-amino acid oxidase (pkDAO) from porcine kidney (Y228L/R283G) and (I230A/R283G). Active primary imines produced as intermediates in the oxidation of methylbenzylamine (MBA) derivatives were trapped by aliphatic, aromatic amines and diamines as nucleophiles forming new imines. ()-Fluoro-MBA was the best substrate for symmetric imine synthesis, providing almost stoichiometric conversion (100 mM) and achieving nearly 100% yield.
View Article and Find Full Text PDFACS Omega
January 2025
School of Chemistry, University of Southampton, Southampton SO17 1BJ, United Kingdom.
Seventeen 3-alkylaminoquinoxaline-2(1)-thiones and 3-alkyloxyquinoxaline-2(1)-thiones were prepared by a novel thionation protocol from the readily available quinoxaline-2,3-dione in excellent overall yields. This protocol starts with the chlorination of dione using thionyl chloride to give 2,3-dichloroquinoxaline followed by the reaction with equimolar amounts of -nucleophiles (primary amines and secondary amines) or -nucleophiles (phenols and alcohols) to principally afford 2-alkanamino-3-chloroquinoxalines or 2-alkyloxy-3-chloroquinoxalines, respectively. The chloroquinoxalines reacted with the thionation reagent -cyclohexyl dithiocarbamate cyclohexyl ammonium salt in ethanol under reflux to principally give the corresponding quinoxalin-2-yl cyclohexylcarbamodithioate that finally rearranges to give the corresponding thiones in 76-93% overall yields.
View Article and Find Full Text PDFMicrosurgery
January 2025
Service de Chirurgie Plastique et Reconstructrice, Hôpital européen Georges-Pompidou, Paris, France.
Objective: The optimal method for maintaining intraoperative blood pressure during microsurgical procedures remains controversial. While intravenous fluid administration is essential, overfilling can lead to complications. Vasopressor agents are used cautiously due to their vasoconstrictive effects, which could potentially lead to flap failure.
View Article and Find Full Text PDFJ Integr Neurosci
January 2025
Neuroscience Department, University of Connecticut Health, School of Medicine, Institute for Systems Genomics, Farmington, CT 06030, USA.
Background: In neuroscience, Ca imaging is a prevalent technique used to infer neuronal electrical activity, often relying on optical signals recorded at low sampling rates (3 to 30 Hz) across multiple neurons simultaneously. This study investigated whether increasing the sampling rate preserves critical information that may be missed at slower acquisition speeds.
Methods: Primary neuronal cultures were prepared from the cortex of newborn pups.
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