Here, we present a metal-free photosensitized three-component reaction for the carboimination of alkenes based on oxime carbonates. Homolysis of oxime carbonates via light-mediated energy transfer enables the simultaneous generation of iminyl radicals and alkoxycarbonyloxyl radicals. The alkoxycarbonyloxyl and alkoxy radicals can act as an effective hydrogen atom transfer reagent, abstracting hydrogen atoms from alkanes and aldehydes, silanes, and phosphine oxide.
View Article and Find Full Text PDFA new two-step, one-pot synthesis of benzo[][1,2]thiazepine 1,1-dioxides was developed, which contains a visible-light mediated aza Paternò-Büchi reaction of benzo[]isothiazole 1,1-dioxides with alkenes and a Lewis acid catalyzed ring-expansion of azetidine. In this work, the mechanism of the aza Paternò-Büchi reaction was also investigated.
View Article and Find Full Text PDFA Sc(OTf) catalyzed intramolecular cyclization reaction of 2-alkyl-1,4-benzoquinone derived from D-A cyclopropane was discovered. This reaction involves single-electron transfer, proton-transfer, an aromatization driven spin center shift, and radical coupling processes, and offers an efficient method for the synthesis of 6-chromanols from D-A cyclopropanes.
View Article and Find Full Text PDFPyridinium 1,4-zwitterionic thiolates are usually used to develop ionic annulation reactions. However, radical reactions were rare. We developed a photoredox catalyzed [3 + 2]-annulation reaction of pyridinium 1,4-zwitterionic thiolates with alkenes, disclosed the new reactivity of pyridinium 1,4-zwitterionic thiolate, and provided a new synthetic method for dihydrothiophene.
View Article and Find Full Text PDF[2 + 2]-Cycloaddition is the most straightforward approach to the construction of cyclobutanes. In this paper, the intermolecular [2 + 2]-cycloaddition reaction of 3-alkylideneindolin-2-ones with alkenes was achieved. This reaction can be used in the synthesis of 3-spirocyclobutyl oxindoles, polycyclic oxindoles, and late stage modification of some drug molecules.
View Article and Find Full Text PDFOver 400,000 people are estimated to have been exposed to World Trade Center particulate matter (WTC) since the attack on the Twin Towers in Lower Manhattan on September 11, 2001. Epidemiological studies have found that exposure to dust may cause respiratory ailments and cardiovascular diseases. However, limited studies have performed a systematic analysis of transcriptomic data to elucidate the biological responses to WTC exposure and the therapeutic options.
View Article and Find Full Text PDFBackground: Diabetes mellitus (DM) is a major risk factor for tuberculosis (TB). Evidence has linked the DM-related dysbiosis of gut microbiota to modifiable host immunity to Mycobacterium tuberculosis infection. However, the crosslinks between gut microbiota composition and immunological effects on the development of latent TB infection (LTBI) in DM patients remain uncertain.
View Article and Find Full Text PDFBackground: Drug repurposing is a fast and effective way to develop drugs for an emerging disease such as COVID-19. The main challenges of effective drug repurposing are the discoveries of the right therapeutic targets and the right drugs for combating the disease.
Methods: Here, we present a systematic repurposing approach, combining Homopharma and hierarchal systems biology networks (HiSBiN), to predict 327 therapeutic targets and 21,233 drug-target interactions of 1,592 FDA drugs for COVID-19.
BMC Bioinformatics
April 2022
Background: The gene signatures have been considered as a promising early diagnosis and prognostic analysis to identify disease subtypes and to determine subsequent treatments. Tissue-specific gene signatures of a specific disease are an emergency requirement for precision medicine to improve the accuracy and reduce the side effects. Currently, many approaches have been proposed for identifying gene signatures for diagnosis and prognostic.
View Article and Find Full Text PDFUsing diverse carbon-centered radical precursors and electron-rich (hetero)aromatics and alcohols as nucleophiles, a visible-light driven chiral phosphoric acid (CPA) catalyzed asymmetric intermolecular, three-component radical-initiated dicarbofunctionalization and oxytrifluoromethylation of enamines was developed, which provides a straightforward access to chiral arylmethylamines, aza-hemiacetals and γ-amino acid derivatives with excellent enantioselectivity. As far as we know, this is the first example of constructing a chiral C-O bond using simple alcohols visible-light photocatalysis. Chiral phosphoric acid played multiple roles in the reaction, including controlling the reaction stereoselectivity and promoting the generation of radical intermediates by activating Togni's reagent.
View Article and Find Full Text PDFExcitatory-inhibitory imbalance (E/I) is a fundamental mechanism underlying autism spectrum disorders (ASD). TRIM32 is a risk gene genetically associated with ASD. The absence of TRIM32 causes impaired generation of inhibitory GABAergic interneurons, neural network hyperexcitability, and autism-like behavior in mice, emphasizing the role of TRIM32 in maintaining E/I balance, but despite the description of TRIM32 in regulating proliferation and differentiation of cultured mouse neural progenitor cells (NPCs), the role of TRIM32 in cerebral cortical development, particularly in the production of excitatory pyramidal neurons, remains unknown.
View Article and Find Full Text PDFHere we describe a metal-free amino-heteroarylation of unactivated olefins organic photoredox catalysis, providing a concise and efficient approach for the rapid synthesis of various δ (β, ε)-amino ketones under mild conditions. This protocol demonstrates that the new photocatalyst Cz-NI developed by our group has an excellent photoredox catalytic performance. Finally, a series of mechanistic experiments and DFT calculations indicate that this transformation undergoes a photoredox catalytic sequential radical addition/functional group migration process.
View Article and Find Full Text PDFHerein, we report an efficient photoinduced radical tandem trifluoromethylation/cyclization reaction of -cyanamide alkenes for the synthesis of functionalized quinazolinones. Importantly, the reaction is carried out under mild conditions without any additional photosensitizer, metal, or extra additives. A series of trifluoromethyl quinazolinones were prepared efficiently with good yields and excellent functional group tolerance.
View Article and Find Full Text PDFDiabetes mellitus (DM) is a major metabolic disorder and an increasing health problem worldwide. Effective non-invasive therapies for DM are still lacking. Here, we have developed Microcurrent electrical nerve stimulation (MENS), a non-invasive therapy, and tested on 46 mice clustered into five groups, such as control, STZ-induced DM, and MENS treatment groups.
View Article and Find Full Text PDFA novel one-pot triple-reaction strategy for the asymmetric construction of polycyclic skeletons with multiple consecutive chiral centers through aza-Michael/Michael/Wittig/ketyl radical addition/esterification processes is reported. A wide range of polycyclic tetrahydroquinoline derivatives were smoothly obtained from easily available starting materials with good results (up to 80% yield, >20:1 dr, >99% ee) under mild conditions. In this transformation, five chemical bonds and five consecutive chiral centers were successively formed.
View Article and Find Full Text PDFZhongguo Yi Xue Ke Xue Yuan Xue Bao
August 2020
To compare the short-and long-term effect of two minimal invasive surgical therapies including keyhole approach endoscopic surgery(KAES)and stereotactic aspiration plus urokinase(SAU)in treating basal ganglia hypertensive intracerebral hemorrhage(hICH). The clinical data of 117 hICH patients(63 received KAES and 54 received SAU)were retrospectively analyzed.The operation time,blood loss during surgery,and drainage time were compared between two groups.
View Article and Find Full Text PDFA series of novel biselectrophilic β,γ-unsaturated α-ketoesters were designed and synthesized from rhodanine. Under the catalysis of chiral squaramides, the enantioselective [3 + 3] annulation reaction of these novel ketoesters with pyrazolones was developed. This reaction offers an efficient method for the synthesis of chiral 2'-thioxo-5,6-dihydrospiro[pyrano[2,3-]pyrazole-4,5'-thiazolidin]-4'-ones.
View Article and Find Full Text PDFThe primary type of liver cancer, hepatocellular carcinoma (HCC), has been associated with nonalcoholic steatohepatitis, diabetes, and obesity. Previous studies have identified some genetic risk factors, such as hepatitis B virus X antigens, overexpression of SRC oncogene, and mutation of the p53 tumor suppressor gene; however, the synergism between diet and genetic risk factors is still unclear. To investigate the synergism between diet and genetic risk factors in hepatocarcinogenesis, we used zebrafish with four genetic backgrounds and overfeeding or high-fat-diet-induced obesity with an omics-based expression of genes and histopathological changes.
View Article and Find Full Text PDFA variety of axially chiral biaryldiols were synthesized in good yields with excellent atropo-enantioselectivities through construction of axially chiral indoles catalyzed by asymmetric hydrogen-bond donors. In addition, the new axially chiral compounds were proved to be efficient and practical catalysts for asymmetric catalysis. The strategy not only provides a novel method to synthesize axially chiral compounds but also extends the scope of chiral catalysts.
View Article and Find Full Text PDFSymmetric peripheral gangrene is a rare but devastating complication, scarcely reported after brain surgery. We present a case of symmetric peripheral gangrene shortly after brain surgery of intracranial hematoma removal and aneurysm clipping.
View Article and Find Full Text PDFA synergistic catalytic method combining photoredox catalysis, hydrogen-atom transfer, and proton-reduction catalysis for the dehydrogenative silylation of alkenes was developed. With this approach, a highly concise route to substituted allylsilanes has been achieved under very mild reaction conditions without using oxidants. This transformation features good to excellent yields, operational simplicity, and high atom economy.
View Article and Find Full Text PDFHere a highly efficient cascade approach is reported that combines a cycloaddition reaction with a regioselective strain-release process to afford diverse heterocyclic frameworks through bifunctional catalysis. The cooperation of hydrogen-bonding network activation and a regiodivergent strain-assisted effect is the key to promoting this complex chemical transformation, leading to the generation of two different ring systems in high yields with excellent stereoselectivities. The reaction proceeded by a mechanism involving a "spring-loaded" intermediate with switchable C-C bond cleavages achieved by controllable ring-strain release.
View Article and Find Full Text PDFA novel synthesis of five-membered cyclic nitrones has been developed based on the Lewis acid-catalysed [3+2]-annulation reaction of D-A cyclopropanes with 1,4,2-dioxazoles. Broad substrate scope and generally good yield make this reaction useful in the preparation of nitrones. When a suitable 1,4,2-dioxazole was used, nitrone and tetrahydrofuran could be prepared in one pot with high atom economy.
View Article and Find Full Text PDFA C-symmetric -heterocyclic carbene (NHC)-catalysed activation of isatin-derived enals under oxidative conditions was achieved. The generated α,β-unsaturated acyl azolium species was efficiently trapped by 1,3-dicarbonyl compounds a Michael addition/spiroannualtion cascade, delivering a series of synthetically important spirooxindole δ-lactones with up to 96% enantioselectivity.
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