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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

The remarkable but varied photosensitized oxidation by atmospheric humic-like substances at the air-water interface

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Science China chemistry 2024年

作者： Ning Yang Chu Gong Dongmei Zhang Xufeng Gao Lifeng Han Pingqing Fu Xinxing Zhang Institute of Surface-Earth System Science School of Earth System Science Tianjin University College of chemistry Frontiers Science Center for New Organic Matter State Key Laboratory of Advanced Chemical Power SourcesKey Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Tianjin Key Laboratory of Biosensing and Molecular Recognition Renewable Energy Conversion and Storage Center (ReCAST) Nankai University State Key laboratory of Component-Based Chinese Medicine Haihe Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese Medicine

Humic-like substances(HULIS), a class of macromolecular photosensitizers, are major components of light-absorbing aerosols in the atmosphere. Due to the amphiphilic nature of HULIS, they tend to appear at the air-water interface of atmospheric ***, there have been limited studies on the photosensitized chemistry of HULIS at the air-water interface owing to the lack of methods with high interface selectivity. Here, a unique field-induced droplet ionization mass spectrometry(FIDI-MS)technique was used to investigate the photosensitized chemistry of several samples at the air-water interface. These samples include commercially available humic acid and the PM2.5sample collected during Beijing′s severe winter haze in December2016. Ultrahigh-resolution Fourier transform-ion cyclotron resonance mass spectrometry(FT-ICR MS) was also applied to analyze the atomic compositions, the degree of unsaturation and the aromaticity of these samples. Both Type I and Type II photosensitized oxidation pathways were observed, which were postulated to be dictated by the packing density of the molecules at the air-water interface. These findings reveal that the photosensitization of HULIS at the air-water interface contributes greatly to the formation of atmospheric aerosols, further advancing our understanding of the important roles played by photosensitized chemistry in the atmosphere.

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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.

Synthesis of new heterocycles 1,3,2,6-dioxaphosphaselenacyclooctanes

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Chinese Journal of chemistry 1997年第5期15卷 450-458页

作者： Li, JL Tian, B Zhao, CQ Wang, YM Meng, JB Wang, HG nankai Univ Dept Chem Tianjin 300071 Peoples R China nankai Univ Cent Lab Tianjin 300071 Peoples R China

New phosphorus-and selenium containing heterocyclyes, 1,3,2,6-dioxaphosphaselena-cyclooctanes (1a-1h), were synthesized by the reaction of bis(2-hydroxyethyl)selenide with RP(X)Cl-2 where R=alkoxyl, aroxyl, aryl. and X=O or lone pair. Their structures were determined by spectroscopies and elemental analyses and finally confirmed by the X-ray crystallographic analysis of 1c. The molecular structures of the heterocycles were discussed in term of conformational analysis.

关键词： heterocycles synthesis structure

First Total Synthesis of 4,5-Sccoeudesmane-type and Iphionane-type Compounds-Synthesis of 4,5-Dioxo-seco-γ-eudesmol and 5β,11-Dihydroxyiphionan-4-one

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Chinese Chemical Letters 2000年第2期11卷 113-114页

作者： Zhao Ming XIONG Gang ZHOU Xiao Lei GAO Yong Gang CHEN Yu lin LI (national laboratory of Applied organic chemistry and Institute of organic chemistry, Lanzhou university, Lanzhou 730000) Natl. Lab. of Appl. Organ. chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 730000 China

4, 5-Secoeudesmane-type and iphionane-type compounds are sesquiterpenes with new carbon skeletons found in natrual sources in recent years.1-6 The co-occurence of 4, 5-secoeudesmanes, iphionanes and eudesmanes as natrual products suggests that 4, 5-secoeudesmanes, iphionanes most likely are generated biogenetically from eudesmanes, and iphionanes are formed biogenetically by aldol reaction of 4, 5-dioxosecoeudesmanes1,4,6,7. The study on the synthesis of this two kind of new sesquiterpenes has not been reported in the literature.

关键词： type First Total Synthesis of 4,5-Sccoeudesmane-type and Iphionane-type Compounds-Synthesis of 4,5-Dioxo-seco eudesmol and 5 Dihydroxyiphionan-4-one

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.