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Pd-catalyzed asymmetric carbonyl alkynylation:Synthesis of axial chiral ynones

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Chinese chemical Letters 2024年第6期35卷 293-297页

作者： Long Jin Jian Han Dongmei Fang Min Wang Jian Liao natural products research Center Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China College of chemical Engineering Sichuan UniversityChengdu 610065China University of Chinese Academy of Sciences Beijing 100049China

Ynones are important skeletons in bioactive molecules and valuable building blocks for organic synthesis,thus great efforts have been devoted to their ***,introducing prochiral substrates to construct ynones bearing a chiral framework is unrealized to ***,we reported the first example of Pd/SOP-catalyzed asymmetric carbonylative alkynylation via a non-classical carbonylative Sonogashiratype approach(acyl-Pd(Ⅱ)species generated from nucleophiles).By using cyclic diaryliodonium salts as prochiral substrates,various axial chiral ynones with good functional group tolerance(39 examples),satisfied yields(71%-96%)and excellent enantioselectivities(generally 94%-99%ee)were *** of bioactive compounds,scale-up experiment and useful transformations were also conducted to demonstrate the utility of this process.

关键词： Pd-catalyzed Axial chiral ynones Cyclic diaryliodonium High-valent palladium catalyzed Asymmetric carbonyl alkynylation

Rearranged 19-nor-7,8-seco-labdane diterpenoids and Diels-Alder cycloadducts from the Chinese liverwort Pallavicinia ambigua:Structural elucidation,photoinduced rearrangement,and cytotoxic activity

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Chinese chemical Letters 2024年第3期35卷 415-418页

作者： Chunyang Zhang Yuelan Li Zhaojun Chu Shuangzhi Yuan Yanan Qiao Jiaozhen Zhang Lin Li Yueqing Zhang Ruifeng Tian Yajie Tang Hongxiang Lou Department of natural products Chemistry Key Lab of Chemical Biology(MOE)School of Pharmaceutical SciencesShandong UniversityJi'nan 250012China State Key Laboratory of Microbial Technology Shandong UniversityQingdao 266237China

Two distinctive rearranged 19-nor-7,8-seco-labdane diterpenoids(1 and 2)with a novel tetracyclo[5.***.1.0^(2,5.)0^(4,10)]decane skeleton,a derivative of the open tetrahydrofuran ring(7),three dimeric compounds(8-10),and four revised homologs(3-6)were obtained from Chinese liverwort Pallavicinia *** structures were identified via combined analysis of their spectroscopic data,single-crystal X-ray diffraction patterns,and ECD *** light-driven conversion of compound 5 to compounds 1-4 demonstrated that photochemically induced postmodification involved in biosynthesis is an important way to diversify natural structures.A preliminary cytotoxicity assay revealed that compound 5 showed significant inhibition in the human prostate cancer(PC-3)cell line via an apoptotic pathway.

关键词： Liverwort Pallavicinia ambigua 19-nor-7 8-seco-Labdan diterpenoid Photoinduced rearrangement Cytotoxic activity

Phenylhydrazone anions excitation for the photochemical carbonylation of aryl iodides with aldehydes

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Chinese chemical Letters 2024年第4期35卷 346-351页

作者： Lei Shen Yang Zhang Linlin Zhang Chuanwang Liu Zhixian Ma Kangjiang Liang Chengfeng Xia Key Laboratory of Medicinal Chemistry for natural Resource Ministry of EducationYunnan Provincial Center for Research&Development of Natural ProductsSchool of PharmacyYunnan UniversityKunming 650500China

Spectroscopic investigations discovered that the in-situ generated phenylhydrazone anion was significantly bathochromically shifted to visible light region for photoactivation under irradiation. The photoexcited phenylhydrazone anion was potential to reduce aryl iodides via single electron transfer process for the subsequent radical chain reaction. A redox-neutral photochemical carbonylation of aryl iodides was developed on basis of the special spectroscopic features of phenylhydrazone anion. This protocol provided a convenient and efficient synthetic tool for accessing carbonylation products under redox neutral conditions without the need of transition-metals.

关键词： Organic anion Hydrazone Carbonylation Visible light Single electron transfer

Constituents from leaves of Macaranga hemsleyana

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Chinese Herbal Medicines 2024年第3期16卷 481-486页

作者： Joseph Sakah Kaunda Jia Liu Yaojun Xu Yuansi Chen Chenfang Yue Xingjie Zhang Ruihan Zhang Muhammad Amin Weilie Xiao Hongliang Li Xiaoli Li Key Laboratory of Medicinal Chemistry for natural Resource Ministry of EducationYunnan Characteristic Plant Extraction LaboratoryYunnan Provincial Center for Research & Development of Natural ProductsState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of PharmacySchool of MedicineChemical Science and TechnologyYunnan University Yunnan Key Laboratory of Pharmacology for natural products Haiyuan CollegeKunming Medical University

Objective:To study constituents of the leaves of Macaranga hemsleyana,and evaluate their inhibitory effects against NOD-like receptor thermal protein domain associated protein 3(NLRP3) inflammasome activation,and antiproliferative ***:The constituents were isolated and purified by column chromatography on MCI gel CHP20P/P120,silica gel,Sephadex LH-20,and *** structures of compounds were determined by 1D,2D NMR,and HR-ESI-MS *** inhibitory effect of compounds on inflammasome activation was determined by lactate dehydrogenase(LDH) *** antiproliferative activity was evaluated using MTT ***:The study led to the isolation of 23 compounds,including one new compound,identified as(2Z)-3-[4-(β-D-glucopyranosyloxy)-2'-hydroxy-5'-methoxyphenyl]-2-propenoic acid(1),together with 22known compounds recognized as 1,4-dihydro-4-oxo-3-pyridinecarbonitrile(2),methyl 4-methoxynicotinate(3),4-methoxynicotinonitrile(4),1-(3-O-β-D-glucopyranosyl-4,5-dihydroxyphenyl)-ethanone(5),neoisoastilbin(6),isoastilbin(7),aromadendrin(8),neoastilbin(9),astilbin(10),quercitrin(11),neoschaftoside(12),apigenin 6,8-bis-C-α-L-arabinoside(13),vitexin(14),bergenin(15),scopoletin(16),glucopyranoside salicyl(17),koaburside(18),benzyl β-D-glucoside(19),icariside B5(20),roseoside(21),loliolide(22),and adenosine(23).The tested compounds did not show LDH inhibition nor antiproliferative ***:Compound 1 was a new *** 2 and 3 were obtained for the first time from natural *** 22 known compounds constituted of alkaloids(2-4,23),phenolics(5,15,17,18),flavonoids(6-14),coumarin(16),benzyl glycoside(19),and norsesquiterpenes(20-22).All the compounds,1-23,were revealed from *** for the first *** is the initial uncovering of molecules 1-10,12,13,17-19,and 23 from the genus Macaranga,The isolated compounds,11,14-16,and 20-22established taxonomic classification of *** in Euphorbiaceae *** were outstanding a

关键词： antiproliferative activity chemotaxonomic significance flavonoids glycoside Macaranga hemsleyana Pax et Hoffm NLRP3 inflammasome

Mechanism of action of the bile acid receptor TGR5 in obesity

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Acta Pharmaceutica Sinica B 2024年第2期14卷 468-491页

作者： Weijun Lun Qihao Yan Xinghua Guo Minchuan Zhou Yan Bai Jincan He Hua Cao Qishi Che Jiao Guo Zhengquan Su Guangdong Engineering research Center of natural products and New Drugs Guangdong Provincial University Engineering Technology Research Center of Natural Products and DrugsGuangdong Pharmaceutical UniversityGuangzhou 510006China Guangdong Metabolic Disease research Center of Integrated Chinese and Western Medicine Key Laboratory of Glucolipid Metabolic DisorderMinistry of Education of ChinaGuangdong TCM Key Laboratory for Metabolic DiseasesGuangdong Pharmaceutical UniversityGuangzhou 510006China School of Public Health Guangdong Pharmaceutical UniversityGuangzhou 510310China School of Chemistry and chemical Engineering Guangdong Pharmaceutical UniversityZhongshan 528458China Guangzhou Rainhome Pharm&Tech Co. Ltd.Science CityGuangzhou 510663China

G protein-coupled receptors(GPCRs)are a large family of membrane protein receptors,and Takeda G protein-coupled receptor 5(TGR5)is a member of this *** a membrane receptor,TGR5 is widely distributed in different parts of the human body and plays a vital role in regulating metabolism,including the processes of energy consumption,weight loss and blood glucose *** studies have shown that TGR5 plays an important role in glucose and lipid metabolism disorders such as fatty liver,obesity and *** the global obesity situation becoming more and more serious,a comprehensive explanation of the mechanism of TGR5 and filling the gaps in knowledge concerning clinical ligand drugs are urgently *** this review,we mainly explain the anti-obesity mechanism of TGR5 to promote the further study of this target,and show the electron microscope structure of TGR5 and review recent studies on TGR5 ligands to illustrate the specific binding between TGR5 receptor binding sites and ligands,which can effectively provide new ideas for ligand research and promote drug research.

关键词： Obesity TGR5 Bile acids Ligand Appetite Metabolism GLP-1 Inflammation

A multi-enzymatic cascade reaction for the synthesis of bioactive C-oligosaccharides

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Chinese chemical Letters 2024年第6期35卷 451-455页

作者： Kebo Xie Qian Zhang Fei Ye Jungui Dai State Key Laboratory of Bioactive Substance and Function of natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs and NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

C-Oligosaccharides are rare in nature and possess diverse ***,their chemical synthesis faces many *** this work,enzymatic introduction of C-linked sugar chains to target aglycones was successfully achieved by multi-enzymatic cascade reactions.A C-glycosyltransferase from Aloe barbadensis was employed to introduce the first C-linked glucose and then a cyclomaltodextrin glucanotransferase from Bacillus licheniformis was used to extend the sugar chain.A total of twenty C-oligosaccharides with 2-6 sugars were synthesized from scale-up reactions and exhibited good water solubility and sodium-dependent glucose transporter 2(SGLT2)inhibitory ***,a glucoamylase was used to control the length of the sugar chain and the C-maltosides were efficiently *** findings not only expanded the structural diversity of C-oligosaccharides,but also provided a strategy for the modification of C-glycoside drugs to improve the druggability.

关键词： C-Oligosaccharides C-Glycosyltransferase Cyclomaltodextrin glucanotransferase Glucoamylase Enzymatic synthesis SGLT2 inhibitory activity

A fungal CYP from Beauveria bassiana with promiscuous steroid hydroxylation capabilities

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Chinese chemical Letters 2024年第5期35卷 218-222页

作者： Yu Peng Yue Wang Tian-Jiao Chen Jing-Jing Chen Jin-Ling Yang Ting Gong Ping Zhu State Key Laboratory of Bioactive Substance and Function of natural Medicines NHC Key Laboratory of Biosynthesis of Natural ProductsCAMS Key Laboratory of Enzyme and Biocatalysis of Natural DrugsInstitute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Hydroxylation of steroid core is critical to the synthesis of steroid *** sp^(3) C-H hydroxylation is challenging through chemical catalysis,alternatively,fungal biotransformation offers a possible solution to this ***,mining and metabolic engineering of cytochrome P450 monooxygenases(CYPs)is usually regarded as a more eco-friendly and efficient ***,we report the mining and identification of a new steroid CYP(CYP68BE1)from Beauveria bassiana by transcriptomics,heterologous expression,in vivo and in vitro functional *** catalytic promiscuity of CYP68BE1 was explored,and CYP68BE1 showed promiscuously and catalytically versatile,which is qualified for monohydroxylation on C11α,C1α,C6βand dihydroxylation on C1β,11αand C6β,11αof six steroids,leading to the production of key steroid intermediates required in the industrial synthesis of some indispensable steroid *** dynamics simulations were performed,revealing the molecular basis of different binding orientations of CYP68BE1 with different *** discovery of CYP68BE1 offers a promising biocatalyst for enriching the steroid structural and functional diversity,which also can be applied to biosynthesize valuable steroid drug intermediates.

关键词： Fungal CYPs Steroid hydroxylase Beauveria bassiana Promiscuous biocatalyst Molecular dynamics

Bovine and Goat Milk Fat Globule Membrane Supplementation Alleviates Autism-like Behavior by Modulating Lipid Metabolism and Gut Microbiota

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Food Science and Human Wellness 2024年

作者： Rui Guo Xiao Xiao Chuanchuan Wang Tian Yuan Qianhui Zou Tian Zhang Jiarui Liang Ying He Zhuo Liu Xuebo Liu Shan Wu Zhigang Liu Northwest A&F University Shenzhen research Institute Shaanxi Precision Nutrition and Health research Institute research and Development Center Xi'an Yinqiao Dairy (Group) Co. Ltd Laboratory of Functional Chemistry and Nutrition of Food College of Food Science and Engineering Northwest A&F University Shaanxi Key Laboratory of natural products & chemical biology College of Chemistry & Pharmacy Northwest A&F University

ASD (autism spectrum disorder) is a neurodevelopmental disorder influenced by genes and the environment. This study investigated the protective effects of bovine MFGM (BMFGM) and goat MFGM (GMFGM) supplementation on ASD model mice. Analysis of phospholipid composition showed higher levels of phosphatidylcholine in BMFGM and phosphatidylethanolamine in GMFGM. Behavioral results indicated MFGMs ameliorated social deficits， with GMFGM being more effective. MFGMs mitigated neuroinflammation by suppressing microglial overactivation and proinflammatory cytokines expression， meanwhile GMFGM increased the anti-inflammatory factor IL-10. MFGMs also altered gut microbiota composition and maintained gut barrier integrity. Uniquely， GMFGM increased butyrate production. Correlation analysis revealed positive associations between social behavior， levels of phosphatidylcholine， sphingomyelin， and the abundance of Allobaculum， Clostridium＿sensu＿stricto， and Turicibacter. Overall， these findings revealed the protective effects of MFGMs on neurodevelopment in ASD animal models and the underlying mechanism could be partly explained by their regulation of gut microbiota by the phospholipid components in MFGMs.

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Chiral transfer amidst one-dimensional linear polymers and twodimensional network covalent organic frameworks:Striking a fine balance between helicity and crystallinity

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Nano research 2024年第6期17卷 5726-5734页

作者： Xinlin Zha Mengjuan Zuo Guilin Xu Zhong Yan Haining You Yi Xiong Ying Liu Yingying Li Liyan Yang Ke Liu Mufang Li Tao Zhao Dong Wang College of Chemistry and chemical Engineering Donghua UniversityShanghai 201620China Key Laboratory of Textile Fiber and products Ministry of EducationWuhan Textile UniversityWuhan 430200China

The current landscape of chiral covalent organic frameworks(COFs)predominantly centered on constructing asymmetric molecular-scale chirality,often introducing an inherent contradiction to the COF symmetry and limiting ***,we overcome these challenges by achieving chiral transfer between one-dimensional(1D)imine linear polymers(LPs)and two-dimensional(2D)networkβ-ketoenamine COFs composed of achiral *** successfully synthesize several 1D imine LPs with mesoscopic helical chirality,comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription *** the irreversible tautomerism mechanism within the linker replacement approach,terephthalaldehyde(TPA)units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol(TP),yielding the corresponding 2D networkβ-ketoenamine *** and helicity of the resultantβ-ketoenamine COFs intimately hinge on reaction conditions,including the aldehyde stoichiometry of Tp and TPA,as well as the quantity and concentration of the catalyst *** optimized conditions,the nucleation and growth were precisely governed,achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D networkβ-ketoenamine COFs,even with covalent bond rupture,recombination,and topological transition(from[C2+C2]to[C3+C2]).Impressively,the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D networkβ-ketoenamine *** study not only offers new perspectives on the development of chiral functional COFs,but also provides fresh insights into the precise control of COFs'microscopic morphology.

关键词： chiral covalent organic frameworks chiral transfer dimensional transformation helicity