A novel, highly stereoselective gold-catalyzed spirocyclization of 2-benzyl-3-alkynyl chromone with nitrone is described. This cascade reaction involves gold-catalyzed cycloisomerization, nitrone-olefin [3 + 2]-annulation, alkene oxidation, and rearrangement for the formation of spirocyclic products. Interestingly, the isoxazolidine ring generated from [3 + 2]-annulation donates oxygen to alkene to generate a new pyran-3(4)-one and azetidine ring for dispiro-benzofuran formation upon heating.
View Article and Find Full Text PDFHepatocellular carcinoma is one of the most common malignant tumors in the world and shows strong metastatic potential. Current medicine for hepatocellular carcinoma therapy is invalid, while Georgi exhibits the pharmaceutical potential to treat liver diseases and liver cancer. Herein, we verified the inhibitory properties and the pivotal molecules regimented by on advanced hepatocellular carcinoma.
View Article and Find Full Text PDFA novel cascade Pd(II)-catalyzed - cycloisomerization and olefination reaction of 2-benzyl-3-alkynyl chromones with activated/unactivated alkenes has been developed for the synthesis of fused oxatricyclic compounds. This concise one-pot synthetic approach was applied to the difunctionalization of unbiased alkynes based on 2-benzyl-3-(alkynyl)-4-chromen-4-one via -attack - cycloisomerization, followed by olefination with both activated and unactivated alkenes.
View Article and Find Full Text PDFPsoriasis is a chronic and recurrent skin problem that affects 3% of the global population. Nowadays, most medicines may not promise a complete cure for patients with psoriasis because of the development of pharmacoresistance and the side effects of drugs due to the microenvironment impact in the context of skin imbalance. Herein, we attempt to explore the pharmaceutical efficacy of Scutellaria baicalensis (S.
View Article and Find Full Text PDFA novel Pd-catalyzed chemo- and regiocontrolled tandem cyclization/cross-coupling reaction of 3-alkynyl chromone with aryl iodide was developed for the synthesis of 4-furo[3,2-]chromenes and xanthones. The difunctionalization of alkynes through O-attack/5-- and C-attack/6-- cyclization was reported by this rare approach, which was selectively controlled by the addition of KF or a bidentate phosphine ligand. A one-pot tandem process was demonstrated directly from γ-alkynyl-1,3-diketone for this method.
View Article and Find Full Text PDFChem Commun (Camb)
November 2021
Palladium-catalyzed and ligand-enabled C-H functionalization methods have emerged as a powerful approach for the preparation of therapeutically important motifs and complex natural products. Olefins, owing to their natural abundance, have been extensively employed for the formation of C-C and C-X bonds and the generation of various heterocycles. Traditionally, activated as well as starting materials with preinstalled functional groups, and also halide substrates under transition metal catalysis, have been employed for olefin difunctionalization.
View Article and Find Full Text PDFThe effects of chymosin on the physicochemical and hydrolysis characteristics of casein micelles and individual caseins were investigated. Adding 0.03 units of chymosin/mL led to the casein micelles in skim milk coagulating after a 3 h incubation period at 30 °C.
View Article and Find Full Text PDFHepatic fibrosis is a wound-healing process caused by prolonged liver damage and often occurs due to hepatic stellate cell activation in response to reactive oxygen species (ROS). Red raspberry has been found to attenuate oxidative stress, mainly because it is rich in bioactive components. In the current study, we investigated the inhibitory effects and associated molecular mechanisms of red raspberry extract (RBE) upon activated hepatic stellate cell (aHSC) in cellular and rat models.
View Article and Find Full Text PDFThe inhibitory properties of epicatechin-(4,8)-epicatechingallate (B2-3'gallate), epicatechin gallate (ECG), and epicatechin (EC) isolated from toward maltase and sucrase were investigated. The half-maximal inhibitory concentration (IC) values for maltase were as follows: B2-3'--gallate (1.73 ± 1.
View Article and Find Full Text PDFOrg Biomol Chem
August 2019
In this paper, a novel approach to regioselective α- or γ-hydroarylation of 3-allylchromones with electron-rich arenes has been presented. Results of this study indicated that the regioselectivity was dependent on the substituent at the γ-position of the allyl group. Hydrogen or alkyl substitution favored α-hydroarylation, whereas aryl substitution favored γ-hydroarylation.
View Article and Find Full Text PDFNeuron damage contributes to ischemic brain injury. Although FMS-like tyrosine kinase-3 (FLT3) plays a critical role in neuron survival, its function and molecular mechanism in cerebral ischemia/reperfusion injury is unclear. In the present study, we exposed SH-SY5Y cells to oxygen and glucose deprivation/reoxygenation (OGD/R) to mimic ischemia/reperfusion injury.
View Article and Find Full Text PDFExtensive exposure to UVB (280-320 nm) is the major risk responsible for various skin injuries. Numerous reports have shown that natural products could demonstrate photochemopreventive efficacy against UVB damage. We investigated the preventive effects and associated molecular mechanisms of red raspberry extract upon UVB-caused damage in human epidermal keratinocytes and a nude mouse model.
View Article and Find Full Text PDFAn efficient strategy for synthesizing 3-(2-olefinbenzyl)-4H-chromen-4-one in two steps was developed. The first step is a cyclobenzylation reaction between (E)-3-(dimethylamino)-1-(2-hydroxyphenyl)prop-2-en-1-one and benzyl bromide to produce homoisoflavonoid. The second step involves intermolecular Pd-catalyzed π-chelating-assisted C-H bond olefination.
View Article and Find Full Text PDFParkinson's disease (PD), the second most common neurodegenerative disorder, is characterized by a progressive loss of dopaminergic neurons in the midbrain. Several pathogenetic factors have been involved in the onset and progression of PD, including inflammation, oxidative stress, unfolded protein accumulation, and apoptosis. Ample evidence indicates that miRNAs could regulate post-transcriptional gene expression and neuronal disease.
View Article and Find Full Text PDFThe drugs currently used to treat Alzheimer's disease (AD) are limited in the benefits they confer, and no medication has been clearly proven to cure or delay the progression of AD. Most candidate AD drugs are meant to reduce the production, aggregation, and toxicity of amyloid β (Aβ) or to promote Aβ clearance. Herein, we demonstrate the efficient synthesis of hydroxyl-functionalized stilbene and 2-arylbenzo[b]furan derivatives and report on the neuroprotective and anti-inflammatory effects of these phenolic compounds in vitro and in an animal model.
View Article and Find Full Text PDFThis study investigated the glucono-δ-lactone (GDL)-induced aggregation of isoflavones and soy proteins in soymilk. High-performance liquid chromatography (HPLC) analysis indicated that isoflavones mixed with β-conglycinin (7S) and glycinin (11S) proteins formed 7S-isoflavone and 11S-isoflavone complexes in soymilk supernatant fraction (SSF). Most of the soy protein-isoflavone complexes then precipitated into the soymilk pellet fraction (SPF) following the addition of 4 mM GDL, whereupon the pH value of the soymilk dropped from 6.
View Article and Find Full Text PDFCordyceps sinensis (C. sinensis) has been reported to treat liver diseases. Here, we investigated the inhibitory effect of C.
View Article and Find Full Text PDFUncontrolled inflammation is a leading cause of various chronic diseases. Cinnamaldehyde (CA) is a major bioactive compound isolated from the essential oil of the leaves of Cinnamomum osmophloeum kaneh that exhibits anti-inflammatory activity; however, the use of CA is limited by its cytotoxicity. Here, we synthesized three CA derivatives and identified 4-hydroxycinnamaldehyde-galactosamine (HCAG) as a low toxicity anti-inflammatory compound in vitro (HCAG IC50 ≫ 1600 µM; CA IC50=40 µM) and in vivo.
View Article and Find Full Text PDFTandem reactions use consecutive reaction steps to efficiently synthesize compounds of high molecular complexity. This paper presents a tandem Pd-catalyzed Heck and alkoxycarbonylation reaction for the stereoselective synthesis of (E)-oxindolylidene acetates. The mechanism underlying the Pd-catalyzed tandem reaction involves the syn-carbopalladation of ynamides followed by alkoxycarbonylation with CO and alcohol.
View Article and Find Full Text PDFThe coagulation of β-conglycinin (7S), glycinin (11S) and isoflavones induced by calcium chloride was investigated. Approximately 92.6% of the soymilk proteins were coagulated into the soymilk pellet fraction (SPF) after the addition of 5 mM calcium chloride.
View Article and Find Full Text PDFIndirubin, an active component in the traditional Chinese medicine formula Danggui Longhui Wan, shows promising anticancer effects. Meisoindigo is an analog derived from indirubin, which is less toxic and appears to be even more potent against cancer. In considering meisoindigo as a structural template for the development of new drugs, we designed and synthesized a series of 3-ylideneoxindole acetamides as novel anticancer agents.
View Article and Find Full Text PDFThis study synthesized a series of hydroxyl-functionalized 2-arylbenzo[b]furans based on the structure of tournefolic acid A and evaluated them for antioxidant and α-glucosidase inhibitory activities. Compounds 5a, 5e, and 5n showed remarkable inhibition of α-glucosidase (IC50 values of 1.9-3.
View Article and Find Full Text PDFBPR0C305 is a novel N-substituted indolyl glyoxylamide previously reported with in-vitro cytotoxic activity against a panel of human cancer cells including P-gp-expressing multiple drug-resistant cell sublines. The present study further examined the underlying molecular mechanism of anticancer action and evaluated the in-vivo antitumor activities of BPR0C305. BPR0C305 is a novel synthetic small indole derivative that demonstrates in-vitro activities against human cancer cell growth by inhibiting tubulin polymerization, disrupting cellular microtubule assembly, and causing cell cycle arrest at the G2/M phase.
View Article and Find Full Text PDFWheatgrass is one of the most widely used health foods, but its functional components and mechanisms remain unexplored. Herein, wheatgrass-derived oligosaccharides (WG-PS3) were isolated and found to induce CD69 and Th1 cytokine expression in human peripheral blood mononuclear cells. In particular, WG-PS3 directly activated the purified monocytes by inducing the expression of CD69, CD80, CD86, IL-12, and TNF-α but affected NK and T cells only in the presence of monocytes.
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