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The Studies of the Reactions of 2,4,6-Triphenylpyrylium Tetrafluoroborate with Amino Acids

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Chinese Chemical Letters 2003年第9期14卷 907-910页

作者： shrong shi lin College of Chemical and Molecular Engineering Peking UniversityBeijing 100871

The reactions of triphenylpyrylium salt 1 with various anuno acids were explored and compared. The reactions with most α-amino acids yielded decarboxylation products 2 via decarboxylation. The reactions with glutamic acid, lysine and ACC (1-aminocyclopropyl-carboxylic acid) gave triphenylpyndine 8, dimer 9 and acid 5a-acc, respectively. The reactions with βand γ-amino acids yielded triphenylpyridine by intramolecular elinunation.

关键词： Triphenylpyrylium salt pyridinium betaine pyridinium ylid decarboxylation amino acids intramolecular elimination.

The Synthesis and Regioselective Hydrolysis of Dialkyl 2-Phenylfuran (and 2-Phenyltetrahydrofuran) -3,4-dicarboxylates

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Chinese Chemical Letters 2002年第9期13卷 826-829页

作者： shrong shi lin Bo YANG College of Chemical and Molecular Engineering Peking UniversityBeijing 100871

Dialkyl 2-phenylfuran (and 2-phenyltetrahydrofuran)-3,4-dicarboxylates (1, 2, 5-7), which are potential precursors of the synthesis of furofuran and tetrahydrofurofuran lignans, can be selectively hydrolyzed to monoacid (3, 8) by potassium hydroxide. The regioselective hydrolysis was affected significantly by the 2-phenyl group of the furan or tetrahydrofuran skeleton. The geometric structures of 3, 8 and related compounds were elucidated and verified by NMR spectra.

关键词： Regioselective hydrolysis NMR spectra dimethyl 2-phenylfuran-3,4-dicarboxylate.

Efficient Synthesis of 2,6-Diphenyl-4-arylpyrylium Tetrafluoroborate

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Chinese Chemical Letters 2002年第7期13卷 605-606页

作者： shrong shi lin Cheng Yong LI Xuan WANG Department of Chemistry Peking UniversityBeijing 100871

Four pyrylium salts, (2,6-diphenyl-4-arylpyrylium tetrafluoroborate, aryl = C6H5, 4-MeO C6H4, 4-Me2NC6H4, 4-NO2C6H4) were synthesized efficiently and economically from acetophenone and substituted chalcones in the pre... 详细信息

关键词： Diphenyl-4-arylpyrylium tetrafluoroborate chalcone acetophenone borontrifuo- ride.

The Reactivity of 2,4,6-Tirphenylpyridinium Ylids

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Chinese Chemical Letters 2003年第2期14卷 111-114页

作者： shrong shi lin Jian Mei WANG Cheng Yong LI Department of Chemistry Peking UniversityBeijing 100871

Triphenylpyridinium ylid 2, generated by the decarboxylation of betaine 1, were noted to react with acetyl chloride, chloroform or acetone to form addition-elimination product and proton extraction - carbanion addition products, respectively. The reaction with chloroform was determined as pseudo first order from kinetic experiments. The values of kobsd and t1/2 for decarboxylation at 20, 40 and 50C were calculated to be 4.6 x 10-4, 8.8 x 10-3, 2.8 x 10-2 min-1 and 1.5 x 103, 78, 24 minutes, respectively.

关键词： Pyridinium ylid pyridinium betaine 4-H pyridine kinetic experiment.

The Synthesis of a Novel Phosphorus Containing Antigen

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Chinese Chemical Letters 2001年第6期12卷 497-498页

作者： Gui Yang XIE Jia Hua CHEN shrong shi lin Sheng JIN Ministry of Education Key Lab of Bioorganic Chemistry&Molecular Engineering College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871

Antigen 12, containing a phosphonyl peptide hapten with free C-terminal carboxylic group, was synthesized by 11 reaction steps. The design of the hapten was based on the transition state of peptide hydrolysis catalyze... 详细信息

关键词： Phosphonyl peptide hapten peptide hydrolysis

Preparation and Reactions of Pyridinium Ylids via Decarboxylation of Pyridinium Betaines

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Chinese Chemical Letters 2002年第7期13卷 597-600页

作者： shrong shi lin Jian Mei WANG Xuan WANG Cheng Yong LI College of Chemical and Molecular Engineering Peking UniversityBeijing 100871

Pyridinium ylids 4 were generated as reaction intermediates from the decarboxylation of pyridinium betaines 3, which were prepared from the reactions of a-amino acid ester hydrochlorides with 2, 4, 6-triphenylpyrylium tetrafluoroborate. Protonation, addition and substitution reactions of 4 with electrophiles were studied in this paper.

关键词： Pyridinium betaine pyridinium ylid decarboxylation electrophile.

Spectral and Mechanistic Studies of the Reactions of Substituted 1,5-Benzothiazepine with Dichloroacetyl Chloride and Triethylamine

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Chinese Chemical Letters 2001年第10期12卷 851-854页

作者： Xin ZHOU shrong shi lin Jin Fang YUAN Zhe Ming WANG Hong Zhong WANG College of Chemical and Molecular Engineering Peking UniversityBeijing 100871 Department of Biological Sciences&Biotechnology Tsinghua UniversityBeijing 100084

A [2+2] cycloaddition adduct 2 and a novel ring-opening product 3 were obtained from the reactions of 2,3-benzothiazepines 1 with dichloroacetyl chloride and triethylamine. The relative ratios of 2 and 3 were affected by the addition order of reactants and reaction temperature. The structures were determined by spectral data and the reaction mechanisms for the formation of 2 and 3 were elucidated.

关键词： benzothiazepine dichloroacetyl chloride cycloaddition adduct ring-opening product

The Synthesis of 4-Arylcarbonyl-3-methoxycarbonyl-2-phenylfurans by Friedel-Crafts Acylation Reactions

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Chinese Chemical Letters 2000年第1期11卷 11-14页

作者： shrong shi lin Jun Hua YU Jian Mei WANG Bo YANG Xiu lin YE (Department of Chemistry. Peking University, Beijing 100871) Department of Chemistry Peking University Beijing 100871 China

Keto esters 8, 4-arylcarbonyl-3-methoxycarbonyl-2-phenylfurans, potential precursors of the synthesis of furofuran lignans, were obtained from dimethyl 2-phenylfuran-3,4-dicarboxylate 2. Diester 2 was selectively hydrolyzed to monoacid 6 followed by converting to its acid chloride 7. Friedel-Crafts acylation reactions of 7 with aromatic compounds afforded keto esters 8. The geometric structures of 8 and its precursors were elucidated and verified by NMR spectra.

关键词： Friedel-Crafts acylation selective mono hydrolysis furofuran lignan

Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

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Neural Regeneration Research 2025年第8期20卷 2153-2168页

作者： Xinyu You lin Niu Jiafeng Fu shining Ge Jiangwei shi Yanjun Zhang Pengwei Zhuang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjinChina Haihe Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjinChina First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina

Traumatic brain injury is a prevalent disorder of the central nervous *** addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are *** dysfunction is a significant consequence of traumatic brain *** the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous *** gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated *** comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut ***,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain *** review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effec

关键词： traumatic brain injury brain-gut-microbiome axis gut microbiota neuroimmune immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry