Visible light-promoted α-aminoalkyl radical-triggered α-aminoalkylation and α-diaminoalkylation of Morita-Baylis-Hillman acetates with -methyl arylamines to synthesize -containing alkyl acrylates and γ,γ-diaminobutyl esters was reported. Photoinduced α-aminoalkylation is carried out with Na-eosin Y as an organophotocatalyst at room temperature under metal- and oxidant-free conditions. In particular, the α-diaminoalkylation is performed via α-aminoalkyl radical addition/elimination followed by a catalyst-controlled selective α-aminoalkyl radical addition strategy in one step under the [Ir(dtbbpy)(bpy))]PF/KF catalytic system.
View Article and Find Full Text PDFTwo categories of supramolecular polymer monomers were produced by introducing the ureidopyrimidone quadruple-hydrogen bonding assemblies on the calix[4]arene and the β-cyclodextrin host units. The adsorption capacity of these supramolecular polymers for different metal ions was investigated by static adsorption. The results showed that at pH = 6 and when the adsorption equilibrium was reached, the supramolecular polymer with calixarene and β-cyclodextrin as the main body adsorbed up to 99% of Pb and Cd, respectively.
View Article and Find Full Text PDFA novel photocatalytic protocol for effective and efficient synthesis of cyclic 1,5-diketones containing chroman-4-one skeletons in moderate to good yields radical cascade acylmethylation/cyclization of 2-(allyloxy)arylaldehydes with α-bromo ketones has been described. This reaction features a broad substrate scope, good functional group tolerance, and metal- and oxidant-free conditions. An acylmethyl radical-triggered cascade cyclization was involved.
View Article and Find Full Text PDFRecent years have witnessed a significant advancement in brain imaging techniques that offer a non-invasive approach to mapping the structure and function of the brain. Concurrently, generative artificial intelligence (AI) has experienced substantial growth, involving using existing data to create new content with a similar underlying pattern to real-world data. The integration of these two domains, generative AI in neuroimaging, presents a promising avenue for exploring various fields of brain imaging and brain network computing, particularly in the areas of extracting spatiotemporal brain features and reconstructing the topological connectivity of brain networks.
View Article and Find Full Text PDFA novel three-component Pd/norbornene cooperative catalysis cascade decarboxylative [2+2+2]/[2+2+3]cyclization of 4-iodoisoquinolin-1(2)-ones and -bromobenzoic acids or 8-bromo-1-naphthoic acid has been developed. The method affords a range of fused phenanthridinones and hepta[1,2-]isoquinolinones and displays unique regioselectivity and broad substrate scope. Palladium/norbornene (Pd/NBE)-catalyzed C-H activation and subsequent decarboxylative coupling reactions were involved, and NBE acts as a building block for the construction of rigid nonplanar molecular architectures.
View Article and Find Full Text PDFTwelve dihydrostilbenes (including five new analogues) were prepared by the Witting-Hornor reaction from appropriate aromatic aldehydes and phosphonate esters, followed by hydrogenation in five steps. The inhibition activity against human neutrophil elastase (HNE) of these dihydrostilbenes was evaluated, and three 1,2-dihydroxylated dihydrostilbenes (, , and ) exhibited stronger inhibitory activity against HNE than other analogues.
View Article and Find Full Text PDFA new abietane mono-norditerpenoid, nagiol A (1), along with three known diterpenoids were isolated from the leaves of Podocarpus nagi. Their structures were elucidated by means of extensive spectroscopic analysis. This is the first report of abietane mono-norditerpenoid separated from plant of the genus Podocarpus.
View Article and Find Full Text PDFA new cyclopeptide, neriitide A (1) and a new lignan, neriilignan (2), along with six known compounds including two diterpenoids, three sesquiterpenoids and one sterol were isolated from the leaves of Podocarpus neriifolius. Their structures were elucidated by means of extensive spectroscopic analysis including HREIMS, 1D and 2D NMR techniques. This is the first report of cyclopeptide and lignan separated from this plant.
View Article and Find Full Text PDFHuman neutrophil elastase (HNE) has been implicated as a major contributor in the pathogenesis of diseases, such as lung disorders and other inflammatory diseases. A series of 12 new nigranoic acid esters were regioselectively synthesised in good yields and evaluated for HNE inhibitory activity. Nigranoic acid exhibited significant inhibitory activity against HNE with the IC50 value of 3.
View Article and Find Full Text PDFA new naphthol, 7-hydroxy-6-methyl-1-naphthoic acid methyl ester (1), together with eight known compounds, 6-hydroxy-7-(hydroxymethyl)-1-isopropyl-4-methyl-naphthalene (2), α-hydroxyacetosyringone (3), hexadecyl ferulate (4), scoparone (5), (+)-syringaresinol (6), stigmast-1,5-dien-3β-ol (7), β-sitosterol (8) and daucosterol (9), were isolated from the twigs and leaves of Pterospermum yunnanense Hsue. Their structures were elucidated by using spectroscopic analysis. All the compounds were isolated for the first time from P.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
October 2013
Theasymmetric unit of the title salt, C19H17N2S(+)·Cl(-)·0.75H2O, contains two symmetrically independent formula units of the carbenium salt along with three water mol-ecules. The water mol-ecules are only 50% occupated, and one of them is positioned in a hydro-phobic pocket not forming any hydrogen bonds.
View Article and Find Full Text PDFAn effective, regioselective C-2 arylation of imidazo[2,1-b]thiazoles catalyzed by Cu(I) has been developed. This arylation proceeded smoothly without promotion of the ligands, and various functional (22 samples) groups were well tolerated. Preliminary mechanistic studies of this arylation are also reported.
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