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cyclization mechanism of monoterpenes catalyzed by monoterpene synthases in dipterocarpaceae

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Synthetic and Systems Biotechnology 2024年第1期9卷 11-18页

作者： Xiaoyun Lu Jie Bai Zunzhe Tian Congyu Li Nida Ahmed Xiaonan Liu Jian Cheng Lina Lu Jing Cai Huifeng Jiang Wen Wang School of Ecology and Environment Northwestern Polytechnical UniversityXi’anShanxi710072China Key Laboratory of Engineering Biology for Low-Carbon Manufacturing Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308China

Monoterpenoids are typically present in the secretory tissues of higher plants,and their biosynthesis is catalyzed by the action of monoterpene synthases(MTSs).However,the knowledge about these enzymes is restricted in a few plant *** are responsible for the complex cyclization of monoterpene precursors,resulting in the production of diverse monoterpene *** enzymatic reactions are considered exceptionally complex in ***,it is crucial to understand the catalytic mechanism of MTSs to elucidate their ability to produce diverse or specific monoterpenoid *** our study,we analyzed thirteen genomes of Dipterocarpaceae and identified 38 MTSs that generate a variety of monoterpene *** focusing on four MTSs with different product spectra and analyzing the formation mechanism of acyclic,monocyclic and bicyclic products in MTSs,we observed that even a single amino acid mutation can change the specificity and diversity of MTS products,which is due to the synergistic effect between the shape of the active cavity and the stabilization of carbon-positive intermediates that the mutation ***,residues N340,I448,and phosphoric acid groups were found to be significant contributors to the stabilization of intermediate terpinyl and pinene *** in these residues,either directly or indirectly,can impact the synthesis of single monoterpenes or their *** revealing the role of key residues in the catalytic process and establishing the interaction model between specific residues and complex monoterpenes in MTSs,it will be possible to reasonably design and engineer different catalytic activities into existing MTSs,laying a foundation for the artificial design and industrial application of MTSs.

关键词： cyclization Monoterpene synthases Intermediate stabilization

cyclization Reaction of α-Triazolyl-α, β-unsaturated Ketones with Phenyl hydrazine

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Chinese Chemical Letters 1998年第11期9卷 979-982页

作者： Guo Feng ZHAO Jun REN Yu Chang LI Gui Yu JIN (Institute of Elemento-Organic Chemistry, National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071) Nankai Univ Inst Elementoorgan Chem Natl Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China

The reaction of α-triazolyl-α, β-unsaturated ketones with phenyl hydrazine was studied. The result indicated that cyclization took place and new heterocyclic compounds of substituted 4,5-2H-pyrazoles were obtained,... 详细信息

关键词： α β-unsaturated ketones phenyl hydrazine triazole cyclization pyrazoles

cyclization and halogenation of substituted o-allylphenols with diacetoxyiodobenzene in the presence of iodine or bromine

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Chinese Chemical Letters 2008年第6期19卷 661-664页

作者： Qi Zhong Zhou Chun Lin He Zhen Chu Chen Department of Chemistry Zhejiang University Hangzhou 310027 China

Substituted 2-halomethyl-2,3-dihydrobenzofurans were synthesized in one pot and in mild yield from substituted o-allylphenols with diacetoxyiodobenzene in the presence of 12 or Br2 in dry CH2Cl2 under reflux.

关键词： 2-Halomethyl-2,3-dihydrobcnzofuran Diacetoxyiodobenzene cyclization Halogenation

Michael addition-based cyclization strategy in the total synthesis of Lycopodium alkaloids

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Science China Chemistry 2016年第9期59卷 1079-1087页

作者： Lin-Rui Zhong Zhu-Jun Yao State Key Laboratory of Coordination Chemistry Institute of Chemical Biology and Drug Innovation School of Chemistry and Chemical Engineering Collaborative Innovation Center of Chemistry for Life Sciences Nanjing University

Lycopodium alkaloids, a unique family of biologically important natural products isolated and characterized from various species of Lycopodium(sensu lato), have attracted extensive attention from chemists and pharmacists in the past three decades. Michael addition-based cyclization has been successfully employed as an elegant and efficient ring-construction protocol of constructing key cyclohexanone intermediates in the total synthesis of Lycopodium alkaloids. This mini-review chooses and summarizes several representative total syntheses of various Lycopodium alkaloids in which intramolecular Michael addition severed as the key methodology.

关键词： Lycopodium alkaloid Michael addition cyclization total synthesis

Ni-catalyzed highly regio- and stereo-selective diborylative cyclization of 1,6-enynes with diboron reagent

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Science China Chemistry 2024年第3期67卷 981-989页

作者： Qitao Guan Zhen Shen Yiqiang Tian Genping Huang Chun Zhang Institute of Molecular Plus Tianjin Key Laboratory of Molecular Optoelectronic ScienceDepartment of ChemistrySchool of SciencesTianjin UniversityTianjin 300072China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

The Ni-catalyzed highly selective diborylative cyclization of 1,6-enynes with diboron reagent has been developed. When pinB-Bdan was used, multiple types of boron-containing functional groups could be installed into organic molecule with great chemoselectivity and regioselectivity though this reaction. Meanwhile, if B_2pai_2 was employed, the asymmetric diborylative cyclization could be well induced by using strategy of dynamic kinetic resolution. Importantly, the above reactions could afford desired product with 100% atomic economy, and could be compatible with different series of substituents. The studies of further transformation well illustrated that different type products could serve diverse synthetic strategy. Notably, the reaction mechanism was intensively studied by density functional theory(DFT) calculations, which could reveal the mechanism of regio- and enantio-selective control.

关键词： nickel-catalyzed organoboron cyclization regioselectivity enantioselectivity

Catalytic hydrative cyclization of aldehyde-ynamides with water for synthesis of medium-sized lactams

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Science China Chemistry 2021年第11期64卷 1985-1989页

作者： Bo-Han Zhu Yan-Xin Zheng Wei Kang Chao Deng Jin-Mei Zhou Long-Wu Ye Key Laboratory of Chemical Biology of Fujian Province State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Jiangsu Key Laboratory of Pesticide Science and Department of Chemistry College of SciencesNanjing Agricultural UniversityNanjing210095China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

A non-noble metal catalyzed hydrative cyclization of aldehyde-ynamides for efficient and practical synthesis of medium-sized lactams(7-to 9-membered rings)is *** with previous hydrative cyclization for the formation of six-membered lactams(cis-form),a totally inverse diastereoselectivity(trans-form)of medium-sized lactams is *** addition,this protocol delivers valuable medium-sized lactams in moderate to good yields with high ***,a rational mechanism to understand this inversion of diastereoselectivity is proposed based on theoretical calculations.

关键词： ynamides cyclization lactams diastereoselectivity N-heterocycles

Divergent Assembly of Functionalized Pyrazolo[1,5-a]pyridine Derivatives via[3+2]cyclization of N-Aminopyridinium Salts with Various Unsaturated Hydrocarbons

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Chinese Journal of Chemistry 2024年第24期42卷 3355-3361页

作者： Xiang Liu Shaohong Ma Shi Yan Xiaotian Shi Shuting Li Yanlong Ma Hua Cao School of Chemistry and Chemical Engineering Guangdong Pharmaceutical UniversityZhongshanGuangdong528458 China

Comprehensive Summary Two reaction modes for metal-free[3+2]cyclization of N-aminopyridinium derivatives withβ-alkoxyvinyl trifluoromethylketones have been described through selective C—O or C—O/C—C bond *** strategy can also be extended to the[3+2]cyclization of N-aminopyridinium derivatives with enaminones and bromoalkynes.A broad range of N-aminopyridinium,N-aminoquinolinium,and N-aminoisoquinolinium salts are well tolerated,enabling the divergent synthesis of trifluoroacylated,non-substituted,acylated,and brominated pyrazolo[1,5-a]pyridine derivatives(62 examples).

关键词： Synthetic methods Alkenes cyclization [3+2]Annulation N-Heterocycles

Rhodium(Ⅱ)-Catalyzed [4+3] cyclization of Triazoles with Indole Derivatives and Its Application in the Total Synthesis of (±)-Aurantioclavine

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Chinese Journal of Chemistry 2021年第5期39卷 1145-1152页

作者： Shengguo Duan Bing Xue Hui Meng Zihang Ye Ze-Feng Xu Chuan-Ying Li Department of Chemistry Zhejiang Sci-Tech UniversityHangzhouZhejiang 310018China

An efficient rhodium(Ⅱ)-catalyzed[4+3]cyclization reaction of 1-sulfonyl-1,2-3-triazoles and indoles was ***[5,4,3-ccflindoles,which are widely distributed in ergot alkaloids with various biological activities,could be obtained in good to excellent *** addition,the total synthesis of(±)-aurantioclavine was completed in four steps from the known compound 1a adopting this[4+3]cyclization as a key step.

关键词： Triazoles Rhodium Alkaloids cyclization Aurantioclavine

Transition-metal-free hydroamination/defluorination/cyclization of perfluoroalkyl alkynes with amidines

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Organic Chemistry Frontiers 2022年第1期9卷 109-116页

作者： Li-Wen Sun Zi-Lun Yu Xin-Long Luo Mengtao Ma Zhi-Liang Shen Xue-Qiang Chu Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China Department of Chemistry and Materials Science College of ScienceNanjing Forestry UniversityNanjing 210037China

An efficient defluorinative net-[3+3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was *** present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination,defluorination,and *** desired pyrimidines could be obtained with good functional group tolerance and moderate to good ***,the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative *** pendantπsystem would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp^(3))–F bond.

关键词： cyclization pyrimidine Transition