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Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-Sheng Nong Hao-fan qian Ying-Chun Chen Pu-Sheng Wang Liu-Zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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Poisson Equation on Some Complete Noncompact Manifolds

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Acta Mathematica Sinica,English Series 2007年第4期23卷 623-638页

作者： Xu qian fan Department of Mathematics Ji'nan University Guangzhou 510632 P. R. China

We study the Poisson equation on some complete noncompact manifolds with asymptotically nonnegative curvature. We will also study the limiting behavior of the nonhomogeneous heat equation on some complete noncompact m... 详细信息

关键词： Poisson equation heat equation Green's function

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Influence of Xingnao Jieyu capsule on hippocampal and frontal lobe neuronal growth in a rat model of post-stroke depression

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Neural Regeneration Research 2012年第3期7卷 187-190页

作者： Wentao fan qian Wang Yongmei Yan Shaanxi University of Chinese Medicine Xianyang 712000 Shaanxi Province China

The present study established a rat model of post-stroke depression using incomplete ischemia induced by unilateral carotid artery ligation in combination with solitary raising and subcutaneous injection of a small dose of reserpine. After intragastric perfusion with 45 mg/100 g, 15 mg/100 g, and 7.5 mg/100 g of Xingnao Jieyu for 7, 14 and 21 days, neuronal morphology in the frontal lobe and hippocampus was improved, depression state and voluntary behaviors were also effectively improved in rats with post-stroke depression. Moreover, the effects of Xingnao Jieyu at a dose of 45 and 15 mg/100 g were similar to the traditional antidepressant Prozac.

关键词： Xingnao Jieyu capsule poststroke depression hippocampus neuron traditional Chinese medicine neural regeneration

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Hyperactivity of the Lateral Septum Leads to Hypersensitivity in Susceptible Mice

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Neuroscience Bulletin 2023年第9期39卷 1466-1468页

作者： fan qian Xia Zhang Bin Zhang Jie Li Neuropsychiatry Research Institute The Affiliated Hospital of Qingdao UniversityQingdao266000China Department of Neurology West China Hospital of Sichuan UniversityChengdu610041China

Everyone needs social interactions,not only humans but also most *** social interaction feedback is a reward,promoting more social behaviors and acting as a stress *** the contrary,negative social interactions such as school bullying may become a type of stress that leads to mental illnesses including anxiety and depression *** social defeat stress(CSDS)is a widely accepted social trauma model in rodents based on repeated social attacks,following which the defeated mice can be classified as susceptible(SUS)and resilient(RES)according to their social performance.

关键词： stress illness contrary

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Plant-Derived Enzymes Producing Chiral Aroma Compounds and Potential Application

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Phyton-International Journal of Experimental Botany 2023年第2期92卷 383-398页

作者： fang Dong qian fan Xinguo Su Lanting Zeng Guangdong Food and Drug Vocational College Guangzhou510520China National Navel Orange Engineering Research Center College of Life SciencesGannan Normal UniversityGanzhou341000China Tropical Agriculture and Forestry Department Guangdong AIB Polytechnic CollegeGuangzhou510650China Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement&Guangdong Provincial Key Laboratory of Applied Botany South China Botanical GardenChinese Academy of SciencesGuangzhou510650China

Aroma(volatile)compounds play important ecological functions in plants,and also contribute to the quality of plant-derived ***,chiral aroma compounds affect their functions in plants and lead to different flavor quality *** of chiral aroma compounds are due to the presence of enzymes producing these compounds in plants,which are generally involved in the final biosynthetic step of the aroma ***,we review recent progress in research on the plant-derived enzymes producing chiral aroma compounds,and their changes in response to environmental *** chiral aroma enzymes that have been reported produce(R)-linalool,(S)-linalool,(R)-limonene,and(S)-limonene,etc.,and these enzymes are found in various plant *** also discuss the origins of enantioselectivity in the plant-derived enzymes producing chiral aroma compounds and summarize the potential use of plants containing enzymes producing chiral aroma compounds for producing chiral flavors/fragrances.

关键词： Aroma chiral enantioselectivity enzyme plant volatile stereochemistry

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TRPC6:an underlying target for human glaucoma

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International Journal of Ophthalmology(English edition) 2012年第4期5卷 523-526页

作者： qian fan Wen-Bin Huang and Xiu-Lan Zhang Zhongshan Ophthalmic Center State Key Laboratory of Ophthalmology Sun Yat-sen University Guangzhou 510060 Guangdong Province China

Glaucoma is one of the leading causes of visual impairment and blindness worldwide. Of known risk factors for glaucoma, an increased in intraocular pressure is most highly correlated with glaucomatous damage. Irrespective of the cause, apoptosis of the retinal ganglion cells is the eventual outcome. It is widely accepted that glaucoma is a neurodegenerative disease that is strongly correlated with central nervous system disorders, such as Alzheimer's disease. These two disorders also share some similarities in pathogenic mechanisms. Recent studies suggest that the transient receptor potential canonical 6 channel could work together with brain-derived neurotrophic factor to promote neuron survival in brain and retina. In this study, we propose that transient receptor potential canonical 6 may contribute to the pathogenesis of human glaucoma and become a potential therapeutic target.

关键词： glaucoma transient receptor potential canonical 6 channel neuroprotection

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Cod liver oil: a potential protective supplement for human glaucoma

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International Journal of Ophthalmology(English edition) 2011年第6期4卷 648-651页

作者： Wen-Bin Huang qian fan and Xiu-Lan Zhang Zhongshan Ophthalmic Center State Key Laboratory of Ophthalmology Sun Yat-sen University Guangzhou 510060 Guangdong Province China

Glaucoma is one of the leading causes of visual impairment and blindness. Improved knowledge of the pathogenesis of this disease has allowed the exploration of new therapeutic methods. In general, elevated intraocular pressure (IOP), oxidative stress, and vascular insufficiency are accepted as the major risk factors for the progression of glaucoma. Many natural compounds have been found beneficial for glaucoma. Nutritional therapies are now emerging as potentially effective in glaucomatous therapy. One nutritional supplement with potential therapeutic value is cod liver oil, a dietary supplement that contains vitamin A and omega-3 polyunsaturated fatty acids (PUFAs). Vitamin A is important for preserving normal vision and it is a well-known antioxidant that prevents the oxidative damage that contributes to the etiology and progression of glaucoma. Vitamin A is also a crucial factor for maintaining the integrity of conjunctival and corneal ocular surfaces, and preventing the impairment of ocular epithelium caused by topical antiglaucomatous drugs. Omega-3 fatty acids are beneficial for glaucoma patients as they decrease IOP, increase ocular blood flow, and improve optic neuroprotective function. In this article, we propose that cod liver oil, as a combination of vitamin A and omega-3 fatty acids, should be beneficial for the treatment of glaucoma. However, further studies are needed to explore the relationship between cod liver oil and glaucoma.

关键词： cod liver oil glaucoma omega-3 fatty acids vitamin A

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Unleashing the Power of Bio-based Thermotropic Liquid Crystal Modifiers:Toughening and Reinforcing Petroleum-based Epoxy Resin without Compromising Other Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1093-1102页

作者： Qing-Yun Lu Hong-Wei Gu Jia-Hui Li qian-qian fan Bei-Tao Liu Yan Kou Xi-Gao Jian Zhi-Huan Weng State Key Laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsLiaoning Technology Innovation Center of High Performance Resin MaterialsDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China Thermochemistry Laboratory Liaoning Province Key Laboratory of Thermochemistry for Energy and MaterialsDalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the *** this study,a bio-based liquid crystal epoxy resin(THMT-E P)with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin(E51)with 4,4'-diaminodiphenylsulfone(DDS)as a curing agent,and the blended systems were evaluated for their thermal stability,mechanical properties,and flame *** results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content,and it reached the a maximum value of 26.5 kJ/m^(2)when the THMT-EP content was 5%,which was 31.2%higher than that of E51/***,the flexural strength,modulus,and glass transition tem perature of the blended system were all simultaneously improved with the addition of *** the same time,the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700℃and decreasing the peak heat release rate and total heat release *** work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin.

关键词： Epoxy resin Toughening Bio-based Thermotropic liquid crystal

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A search for Mg-poor stars using LAMOST survey data

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Research in Astronomy and Astrophysics 2015年第8期15卷 1275-1281页

作者： qian-fan Xing Gang Zhao Yong Zhang Yong-Hui Hou Yue-Fei Wang Yue Wu Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences Nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences

Most Galactic metal-poor stars exhibit enhanced α-abundances（e.g.[Mg/Fe] ～＋0.4） according to previous studies of stellar chemical ***, a handful of metal-poor stars with large deficiencies in Mg（e.g. [Mg/Fe]～-0.2） show severe departures from this α-enhancement trend. The sub-solar[Mg/Fe] ratios of these anomalous stars indicate that they possess different chemical enrichment histories than the majority of Galactic metal-poor stars. In previous work,we presented a method to select Mg-poor metal-poor stars from low-resolution SDSS spectra based on a spectral matching technique. In this paper, a similar method is applied to low-resolution（R ～ 1800） LAMOST spectra. Stellar [Mg/Fe] abundances are determined by using stellar parameters delivered by the LAMOST Data Release2 catalog. From a sample of ～ 60 000 stars with atmospheric parameters in the range Teff = [5500, 6500] K and [Fe/H] = [-2.4, ＋0.5], we select 15 candidate Mg-poor metal-poor stars.

关键词： methods: data analysis—stars: abundance—stars: atmospheres

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Myocardial bridge-related coronary heart disease:Independent influencing factors and their predicting value

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World Journal of Clinical Cases 2019年第15期7卷 1986-1995页

作者： Dong-Hui Zhao qian fan Jun-Xia Ning Xin Wang Jia-Yu Tian Department of Cardiology Beijing Anzhen Hospital Affiliated to Capital Medical UniversityBeijing 100029China Department of Cardiology The First People's Hospital of Pingyuan CountyDezhou 253100Shandong ProvinceChina

BACKGROUND Myocardial bridge(MB)will compress the mural coronary artery(MCA)during the systole and cause myocardial *** the diagnosis of coronary heart disease(CHD),because the structure of MB is difficult to be observed by coronary angiography(CAG),the clinical study of the influence of MB on CHD is *** the advancement of computed tomography coronary angiography technology,detailed observations of the MB anatomy have *** To explore the main influencing factors of MB-related CHD and to find potential indicators for predicting MB-related *** A total of 1718 patients with suspected CHD due to the symptoms of myocardial ischemia were enrolled as *** diagnosed with CHD were included in a CHD group,and patients with no significant abnormalities were included in a control *** the CHD group,patients were divided into an MB-CHD subgroup if MB-related CHD was *** the control group,patients were divided into a simple MB subgroup if MB was *** patient's clinical data and MB-related indicators,including the branch of MB,MB type(superficial/deep type),MB length,MB thickness,systolic and diastolic compression of the MCA,and MCA systolic stenosis rate were recorded and *** regression analysis was used to explore the independent influencing factors of MD-related *** curve was used to analyze the diagnostic efficacy of potential indicators for MB-related *** There were 1060 cases in the CHD group and 658 cases in the control group,and there were 236 cases in the MB-CHD subgroup and 52 cases in the simple MB *** logistic regression analysis showed that the combined MB had a significant effect on the occurrence of CHD(P<0.05).MB thickness,systolic compression,diastolic compression,and MCA systolic stenosis rate had significant effects on the occurrence of MB-related CHD(P<0.05).The area under the curve(AUC)of the combination of these influencing factors for the diagnosis of MB-r

关键词： Myocardial bridge Coronary heart disease Mural coronary artery Computed tomography coronary angiography Independent influencing factor

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