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Synthetic Studies toward Pseudolaric Acids:Radical Cyclization to Form Bridged Scaffold

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Chinese Journal of chemistry 2024年第15期42卷 1699-1705页

作者： Yujie Niu Minggui Lin Hao Cui Yanji Huang Yang Shen Yandong Zhang state key laboratoryof Physical chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian ProvinceicHEMCollege of Chemistryand Chemical EngineeringXiamen UniversityXiamenFujian 361005China

Pseudolaric acids are a family of diterpenoid natural products that exhibit a broad spectrum of biological *** main structural feature of their framework is a trans-fused perhydroazulene bearing a bridged lactone positioned at the junction of the ***,we have developed a radical cyclization strategy that allows flexible tuning of the cyclization process through diverse silicon substitutions on the *** strategy can assist in constructing a series of skeletons with structural resemblance to pseudolaric acids and expedites the construction of the bridged ***,it facilitates the synthesis of the entire skeletal structure of the pseudolaric acidfamily of natural products,excludingthe B-ringfunctionalization.

关键词： Terpenoids Total synthesis Radical cyclization Bridged cycles Regioselectivity

An Efficient Method for α-Alkylation of γ-Butyrolactone

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Chinese Chemical Letters 2002年第11期13卷 1039-1042页

作者： YuanRuMENG YeDiGUAN Departmentofchemistry PekingUniversityBeijing100871 statekeylaboratoryofelemento－organicchemistry NankaiUniversityTianjin300071

This paper provides a simple, convenient and mild condition method for -alkylation of g-butyrolactone. Three types of (E)-a-alkenyl-g-butyrolactone compounds were synthesized by condensation of corresponding aldehydes and g-butyrolactone, using MeONa and EtONa as base. Then the a-alkyl-g-butyrolactones were gained by reducing the former alkenyl compounds through catalytic transfer hydrogenation under Pd/C catalyst with sodium hypophosphite at room temperature.

关键词： Alkylation of -butyrolactone condensation catalytic transfer hydrogenation Pd / C-sodium hypophosphite.

Lipophilicity determination of N-( benzothiazol-2-yl )-α-amino alkyl phosphonic diesters by RP-HPLC and RP-HPTLC

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Chinese Journal of chemistry 2000年第6期18卷 872-876页

作者：张玲李在国黄润秋王琴孙 state key laboratory of elemento-organic chemistry Nankai University Tianjin 300071 China

Using methanol-water mixtures as the mobile phase, the chromatographic retention parameters k' and Rf were determined by reversed-phase high-performance liquid chromatography (RP-HPLC) and reversed-phase high-performance thin-layer chromatography (RP-HPTLC) for N-(benzothiazol-2-yl)-α-amino alkyl phosphoric diesters and the correlation with lipophilicity parameter (Clog P) was established. Log Kw values obtained from RP-HPLC and Rm values obtained from RP-HPTLC can be used to evaluate the lipophilicity of this kind of compounds. Chromatographic method is a good alternative for lipophilicity measurement.

关键词： Reversed-phase HPLC reversed-phase HPTLC N-(benzothiazol-2-yl])-α-amino alkyl phosphonic diesters lipophilicity determination

Thiazolidine Derivatives as Chiral Catalysts in the Enantioselective Addition of Diethylzinc to Benzaldehyde

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Chinese Chemical Letters 2000年第9期11卷 761-764页

作者： Qing Lin MENG Yue Lan LI Yan HE Ye Di GUAN Department of chemistry, Peking university, Beijing 100871 state key laboratory of elemento-organic chemistry, nankai university, Tianjin 300071 Peking Univ Dept Chem Beijing 100871 Peoples R China nankai Univ State Key Lab Elementoorgan Tianjin 300071 Peoples R China

Four types of chiral thiazolidine derivatives were synthesized conveniently from natural L-cysteine and showed good enantioselectivity in up to 90% ee in the addition of diethylzine to benzaldehyde. Their enantioselec... 详细信息

关键词： chiral catalysts enantioselective addition % ee (enantiomeric excess) thiazolidine derivatives

The Synthesis of Glycosyl Phosphite-Pt(II) Complexes

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Chinese Chemical Letters 2004年第2期15卷 171-174页

作者： LingHuaCAO HongYunGAO ChuanJianZHOU YuTingLIU CollegeofchemistryandChemicalEngineering XinjiangUniversityUrumqi830046 statekeylaboratoryofElements-organicchemistry NankaiUniversityTianjin300071

Ethylene glycol phosphorochloridite 1 or catechol phosphorochloridite 2 reacted with isopropylidene derivatives of D-glucose, D-galactose, D-mannose and D-fructose, a series of glycosyl phosphites were obtained. These glycosyl phosphites form optically active complexes with simple Pt (膊) salts. Pt (II) is coordinated to the phosphorus atom, most of the metal complexes are quite stable.

关键词： Glycosyl phosphite metal complex synthesis.

Synthesis of Novel Benzoylphenylurea Chitin Inhibitors from Chlorothalonil

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Chinese Chemical Letters 2003年第12期14卷 1219-1222页

作者： JunLIN ShengJiaoYAN DeShouMAO RongXU LiJuanYANG FuChuLIU DepartmentofAppliedchemistry YunnanUniversityKunming650091 statekeylaboratoryofelemento-organicchemistry NankaiUniversityTianjin300071

Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation ... 详细信息

关键词： Benzoylphenylureas chitin inhibitor chlorothalonil.

Design, Synthesis and Insecticidal Evaluation of Novel N-Pyridylpyrazolecarboxamide Derivatives Containing Isoxazole, Isoxazoline and 1,3,4-Thiadiazole Rings

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Chemical Research in Chinese Universities 2017年第6期33卷 882-889页

作者： HUA Xuewen LIU Chen ZHOU Sha CHEN Minggui XIONG Lixia LI Yongqiang LI Zhengming College of Agronomy Liaocheng University Liaocheng 252000 P. R. China Patent Examination Cooperation Hubei Center of the Patent Office SIPO Wuhan 430205 P. R. China state key laboratory of elemento-organic chemistry Collaborative Innovation Center of Chemical Science and Engineering(Tianfin) Nankai University Tianjin 300071 P. R. China

With the introduction of various heterocyclic rings at the benzene part of anthranilic diamides, a series of N-pylidylpyrazolecarboxamide derivatives containing isoxazole, isoxazoline and 1,3,4-thiadiazole rings was designed, synthesized and evaluated for their insecticidal activities. The structures of the obtained novel target compounds were confirmed by means of 1H NMR, 13C NMR and HRMS. The bioassay results indicated that most of the target compounds displayed moderate or good insecticidal activities against oriental armyworm and diamondback moth at the adopted concentrations compared with chlorantraniliprole, especially compounds Ii andII , of which the LC50 and LC95 values against oriental armyworm were further measured. The structure-activity relationship demonstrated that the introduction of chlorine in benzene ring, bromomethyl and acetoxyl substituents in 4,5-dihydroisoxazole part was more advantageous to improve the corresponding insecticidal activities than the introduction of other substitnents and heterocycles.

关键词： Diamide insecticide N-Pyridylpyrazolecarboxamide Insecticidal activity

Catalytic Asymmetric[2,3]-Sigmatropic Rearrangement of Sulfur Ylides Generated from Carbenoids and Allenic 2-Methylphenyl Sulfide

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Chinese Journal of chemistry 2003年第7期21卷 878-882页

作者：张晓梅马明王剑波 key laboratory of Bioorganic chemistry and Molecular Engineering of Ministry of Education Department of Chemical BiolegyCollege of Chemistry Peking University Beijing 100871 China key laboratory of Bioorganic chemistry and Molecular Engineering of Ministry of Education Department of Chemical Biology College of Chemistry Peking University Beijing 100871 China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071 China

The first investigation on catalytic asymmetric [2,3]-sigmatrop-ic rearrangement of sulfur ylides generated from carbenoids and allenic phenyl sulfide was carried out. Up to 55% ee value was obtained.

关键词： carbenoid sulfur ylide [2 3 ]-sigmatropic rear-rangement catalytic asymmetric synthesis

Research on controllable alkaline soil degradation of 5-substituted chlorsulfuron

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Chinese Chemical Letters 2018年第6期29卷 945-948页

作者： Shaa Zhou Xuewen Hua Wei Wei Minggui Chen Yucheng Gu Sha Zhou Haibin Song Zhengming Li state key laboratory of elemento-organic chemistry Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin) College of Chemistry Nankai University Tianjin 300071 China College of Agriculture Liaocheng University Liaocheng 252000 China Syngenta Jealott's Hill International Research Centre Bracknell RG42 6EY United Kingdom

Sulfonylurea（SU） has become one class of the most important herbicides worldwide due to their ultralow application rate and mammalian toxicity. Recently application licenses of 3 classical SU herbicides chlorsulfuron, metsulfuron-methyl and ethametsulfuron were suspended due to their undesirable long persistence which is incompatible with the particular rotation planting system in China. Our previous study has discovered that electron-donating groups, especially dimethylamino and diethylamino substituents, on the 5 th position of the benzene ring in chlorsulfuron, greatly accelerated its degradation rate in an acidic soil（p H 5.41）. Owing to the natural slower degradation of SUs in alkaline soil,dimethylamino and diethylamino substituted chlorsulfuron Ia and Ib were further studied in an alkaline soil（p H 8.46） with chlorsulfuron as a control. The experimental data indicated that the half-life of degradation（DT50） of Ia was 3.36 days while Ib was 6.25 days which amounted to 30 and 15 folds faster than chlorsulfuron（DT5084.53 days）, respectively. The research confirmed that our newly-designed structures Ia and Ib can hasten their degradation rate in alkaline soil as well as in acidic soil. This structural modification of the classical SU provided an opportunity to control the degradation rate to reduce their impact on relevant environment and ecology.

关键词： Chlorsulfuron Sulfonylurea herbicides Soil degradation Alkaline soil DT50