Publications by authors named "Guo Shu-Chen"

Article Synopsis
  • The study focuses on a method for functionalizing β-CFH-1,3-enynes with nucleophiles through base-mediated reactions, yielding terminal monofluoroalkenes with an alkynyl group in good yields and selectivities.
  • The mixtures produced can be effectively separated using flash chromatography, leading to stereoisomerically pure monofluoroenynes.
  • Further modifications of these monofluoroenynes were conducted, demonstrating the ability to create a variety of different molecular structures, with computational studies explaining the observed diastereoselectivity.
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A 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-catalyzed cascade annulation reaction between -quinamines and 3-formylchromones was developed, affording a series of benzopyrone-fused hydrobenzo[,]indoles in moderate to high yields with excellent diastereoselectivity.

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A base-controlled divergent cyclization between 2-mercaptobenzimidazoles and β-CF-1,3-enynes providing either trifluoromethylated or fluorinated benzo[4,5]imidazo[2,1-][1,3]thiazines has been developed. The β-CF-1,3-enyne, as a three-carbon synthon, underwent a 1,8-diazabicyclo[5.4.

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A new class of Michael acceptor, tetrazolyl-trifluoromethyl alkenes, has been discovered. They readily undergo Michael-type addition instead of addition-elimination reaction with aliphatic amines and azoles to furnish β-trifluoromethyl alkylamines and CF-substituted 1,2-bisazole derivatives, respectively. Additionally, some of the products are capable of engaging in microwave-assisted intramolecular denitrogenative annulation, leading to the formation of CF-substituted 1,4,5,6-tetrahydro-1,2,4-triazines that are otherwise difficult to access by other methodologies.

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Installing a fluoroalkyl group onto the nitrogen atom of azoles represents a potential strategy for lead optimization in medicinal chemistry. Herein, we describe a method for the -trifluoropropylation of azoles. This process is accomplished using a combination of regioselective -vinylation and sequential hydrogenation.

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A base-catalyzed divergent synthesis of multisubstituted imidazoles through TosMIC-based [3 + 2] cyclization reaction has been developed. In the presence of ketenimines and BuONa, 1,4,5-trisubstituted imidazoles were obtained. Nonetheless, in the absence of ketenimines, 1,4-disubstituted imidazole was produced through cyclodimerization of TosMIC.

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Clarifying the mechanisms of Chinese medicinal processing is pivotal to the modernization of Chinese medicine. Research on Chinese medicinal processing gives priority to the mechanisms of the processing in enhancing efficacy, reducing toxicity, and repurposing medicinals. During the past 20 years, scholars have carried out in-depth studies on the mechanisms of Chinese medicinal processing via modern system biology.

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The research on the processing mechanism of Chinese medicine is the key and core foundation to improve processing technologies of Chinese medicine, formulate the quality standards of Chinese medicinal pieces, enhance the clinical efficacy of Chinese medicine, enrich Chinese medicine processing theories, and promote the development of Chinese medicine processing. Many researc-hers have conducted in-depth exploration on the processing mechanism of Chinese medicine in the 20 years in the 21 st century. Significant progress has been made in the transformation of chemical components during the processing, the change of active components in the body, the law of toxicity attenuation in the processing of toxic Chinese medicine, the mechanism of efficacy enhancement and toxicity attenuation of processing with auxiliary materials, and the application of new biomedical technologies.

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Chinese medicine undergoes complex chemical changes during processing and identifying these changes is the key to the processing mechanism. In the past 20 years of the 21 st century, research on the chemical changes in Chinese medicine after processing has focused the changes in the biopharmaceutical process in addition to the variation during processing. With the surging of information technologies, various identification technologies(instrumental analysis techniques, molecular biological techniques, data mining techniques, and biotransformation techniques) have developed rapidly and been widely applied to the research on processing mechanism.

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Although trifluoromethyl alkenes have great synthetic potential, their 1,2-difunctionalization has been a challenge. In this Letter, we disclose the first 1,2-dicarbofunctionalization of trifluoromethyl alkenes with pyridinium salts via a cascade process involving a base-promoted [3 + 2] cycloaddition followed by a visible-light-mediated Norrish-type-II fragmentation. This protocol allows for the formation of pyridines bearing a trifluoromethyl-substituted quaternary center in moderate to excellent yields under mild conditions.

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An interesting β-isoquinidine catalyzed divergent reaction was developed to produce either spirocyclopentene oxindoles, spirocyclopentadiene oxindoles or bisoxindoles in a high enantioselective fashion. The utility of this protocol was demonstrated by the versatile transformations of the products. This work not only represents the first highly stereoselective intermolecular catalytic asymmetric allylic alkylation reaction between two isatin-derived MBH carbonate molecules but also constitutes a rare example of isatin-derived MBH carbonate-based enantioselective and α-regioselective [3+2] cycloaddition reactions.

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Breast cancer is the second leading cause of cancer-related mortality in women, mainly due to metastasis, which is strongly associated with cancer stemness. Our previous studies showed that the eradication of cancer stem-like cells (CSCs) may be related to the activation of dopamine D1 receptor (D1DR). This study aimed to explicitly demonstrate the target-role of D1DR activation in antimetastatic therapy and to investigate the potential efficacy and the underlying D1DR-related mechanisms of QAP14, a new oral compound.

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Stephaniae tetrandrae radix (STR) is a commonly used traditional Chinese medicine in alleviating edema by inducing diuresis. In the clinic, STR extracts or its components are widely used in the treatment of edema, dysuria, and rheumatism for the regulation of water metabolism. Furthermore, STR has been used in treating emotional problems for years by combining with other Chinese herbs.

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The aim of this study was to predict the anti-microbial components in the aerial part of Bupleurum chinense fermented by Lactobacillus plantarum through analyzing the correlation between contents of bioactive components and their inhibitory action for pathogenic bacteria. In this study, the UPLC-MS-MS detection method was established for eight flavonoids(kaempferol-3-O-β-D-rutinoside, isoquercitrin, quercetin, isorhamnetin, rutin, iridin, quercetin-3-O-β-L-arabinoside, kaempferol) and DL-3-phenyllactic acid, and the dynamic change of their contents at fermentation course were monitored. Meanwhile, the experiment employed five common no-naquatic pathogenic bacteria(Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Bacillus subtilis), and four common aquatic pathogenic bacteria(Aeruginosa hydrophila, Delayed Edwards, Vibrio alginolyticus, and Vibrio harveyi) to validate in vitro anti-microbial activity of the fermented aerial part of B.

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The development of catalytic enantioselective isocyanide-based reactions is currently of great interest because the resulting products are valuable in organic synthesis, pharmacological chemistry, and materials science. This review assembles and comprehensively summarizes the recent achievements in this rapidly growing area according to the reaction types. Special attention is paid to the advantages, limitations, possible mechanisms, and synthetic applications of each reaction.

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An expedient and economic approach for constructing O,O,N-spiro compounds consisting of both a 1,3-oxazine and a furan ring through a catalyst-free formal [4+1]/[4+2] cycloaddition cascade sequence of isocyanides with two molecules of acylketene formed in situ through thermal-induced Wolff rearrangement of 2-diazo-1,3-diketones was developed. The reaction displayed good functional group tolerance and was compatible with different isocyanides and 2-diazo-1,3-diketones. Furthermore, preliminary asymmetric attempts of this reaction are made by utilizing optically pure isocyanides as inputs, and moderate diastereomeric induction was observed.

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A one-pot synthesis of 1,3-diyne-tethered trifluoromethylcyclopropanes starting from 2-CF-3,5-diyne-1-enes and sulfur ylides via a sulfur ylide mediated cyclopropanation and a DBU-mediated epimerization sequence is described in this work. This process is highly diastereoselective with broad substrate scope. Moreover, a series of synthetic transformations based on the diyne moieties were conducted smoothly, affording cyclopropanes featuring trifluoromethyl-substituted all-carbon quaternary centers.

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Tandem reactions of Pd-catalyzed cross-coupling of 3-(2-isocyanoethyl)indoles with diazoacetates and subsequent spirocyclization/Mannich-type reaction have been developed to assemble polycyclic spiroindoline skeletons. Formation of spiroindolenines has been proven as the crucial step for the following Mannich-type cyclization reaction. Accordingly, a novel approach on chiral phosphoric acid catalyzed Mannich-type cyclization toward the formation of diastereomerically and enantiomerically enriched pentacyclic spiroindolines has been established.

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Gut microbiota play an important role in metabolism of intake saponins, and parallelly, the polysaccharides deriving from herbal products possess effects on gut microbiota. Ophiopogonis Radix is a common Chinese herb that is popularly used as functional food in China. Polysaccharide and steroidal saponin, e.

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The combined usage of Ginseng Radix et Rhizoma (ginseng) and Ophiopogonis Radix is common in oriental countries for thousands of years. The major active constituents of ginseng are ginsenosides, and the conversion of ginsenosides to different metabolites by gut microbiota has been reported. However, the effect of Ophiopogonis Radix, especially its polysaccharides, on the metabolism of ginsenosides by gut microbiota is not known.

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Leaves of Platycladus orientalis have been used as blood cooling and homeostatic therapy for thousands of years in traditional Chinese medicine. Emerging evidences of modern pharmacology have proved flavonoids as the key elements responsible for the efficacies. However, there has been no report on pharmacokinetic study of the flavonoids from Platycladus orientalis leaves extract.

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Ethnopharmacological Relevance: Schizonepeta tenuifolia Briq. (ST) herbs have been used as a Traditional Chinese Medicine (TCM) for treating colds for thousands of years. The volatile oil is considered as the main material basis responsible for the efficacy of ST and has attracted lots of attention on its anti-inflammatory effect recently.

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Annona squamosa L. fruit played great anti-neoplastic activities. Its pericarps were discarded as waste.

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