Study Objectives: To examine the association between sleep structure and amnesic mild cognitive impairment (aMCI) in patients with insomnia disorder.
Methods: A total of 256 patients with insomnia disorder were diagnosed by neurologists, 45 of whom were diagnosed with aMCI according to the Petersen criteria, and 45 participants with intact cognition were chosen as controls matched for age and education. A case-control study was conducted to compare sleep structure between aMCI and control patients with insomnia disorder.
Seryl-histidine dipeptide (Ser-His) has been recognized as the shortest peptide with hydrolysis cleavage activity; however, its protein cleavage spectrum has not yet been fully explored. Here, four differently folded proteins were treated with Ser-His, and the digestion products were evaluated with high-resolution mass spectrometry. The cleavage efficiency and cleavage propensity of Ser-His against these protein substrates were calculated at both the primary and secondary sequence levels.
View Article and Find Full Text PDFA novel gold-catalyzed tandem cycloisomerization/hydrogenation of chiral homopropargyl sulfonamides has been developed. Various enantioenriched pyrrolidines can be obtained in excellent yields and excellent enantioselectivities by combination of chiral tert-butylsulfinimine chemistry with gold catalysis. Importantly, this represents the first example of a pyrrolidine synthesis from homopropargyl sulfonamide.
View Article and Find Full Text PDFThe generation of gold carbenes the gold-catalyzed intermolecular reaction of nucleophiles containing relatively labile N-O or N-N bonds with alkynes has received considerable attention during recent years. However, this protocol is not atom-economic as the reaction produces a stoichiometric amount of pyridine or quinoline waste, the cleaved part of the N-O or N-N bonds. In this article, we disclose an unprecedented gold-catalyzed formal [3+2] cycloaddition between ynamides and isoxazoles, allowing rapid and practical access to a wide range of synthetically-useful 2-aminopyrroles.
View Article and Find Full Text PDFA direct gold-catalyzed 5-endo-dig cycloisomerization of chiral homopropargyl sulfonamides has been developed. A range of enantioenriched 2,3-dihydropyrroles are readily accessed by utilizing this approach. Importantly, this gold-catalyzed cycloisomerization reaction proceeds through an anti-Markovnikov addition by using a catalytic base as the additive, which completely suppresses the undesired dimerization.
View Article and Find Full Text PDFA gold-catalyzed intermolecular alkyne oxidation for the preparation of 3-coumaranones has been developed. Using 8-isopropylquinoline N-oxides as oxidants, the reactions of o-ethynylanisoles afford versatile 3-coumaranones in moderate to good isolated yields. The synthetic utility of this chemistry is also indicated by the synthesis of the natural product sulfuretin.
View Article and Find Full Text PDFA gold-catalyzed tandem cycloisomerization/functionalization of in situ generated α-oxo gold carbenes in water has been developed, which provides ready access to highly functionalized indole derivatives from o-alkynyl anilines and ynamides. Importantly, gold serves dual catalytic roles to mediate both the cycloisomerization of o-alkynyl anilines and the intermolecular oxidation of ynamides at the same time, thus providing a new type of concurrent tandem catalysis. The use of readily available starting materials, a simple procedure, and mild reaction conditions are other notable features of this method.
View Article and Find Full Text PDFA novel gold-catalyzed intermolecular oxidation of o-alkynylbiaryls has been developed. A variety of functionalized fluorenes are readily accessed by utilizing this non-diazo approach, thus providing a viable alternative to synthetically useful fluorenes.
View Article and Find Full Text PDFA novel gold-catalyzed intermolecular oxidation of o-ethynylanilines has been developed. A range of functionalized 3-oxyindoles are readily accessed by utilizing this strategy. Importantly, this gold-catalyzed oxidative process outcompetes the typical indole formation.
View Article and Find Full Text PDFA gold-catalyzed intermolecular oxidation of chiral homopropargyl sulfonamides has been developed, which provides a reliable access to synthetically useful chiral pyrrolidin-3-ones with excellent ee, by combining the chiral tert-butylsulfinimine chemistry and gold catalysis. This methodology has also been used in the facile synthesis of natural product (-)-irniine. The use of readily available starting materials, a broad substrate scope, a simple procedure and the mild nature of this reaction render it a viable alternative for the synthesis of enantioenriched pyrrolidin-3-ones.
View Article and Find Full Text PDFChin Med J (Engl)
January 2009
Background: The present study was aimed to investigate the usage of aspirin for the secondary prevention of ischemic stroke, evaluate the correlated factors, and analyze the reasons for not taking and irregularly taking aspirin.
Methods: The patients in this group were all stroke survivors who have formerly been diagnosed with a cerebral infarction or transient ischemic attack (TIA) in our hospital. We investigated their use of aspirin over a three-year period following their hospitalization.