Synthesis of phosphinic and phosphoric analogs of aspartic acid

Approaches to the synthesis of 1-amino- and 2-amino-2-carboxyethylphosphinic and-phosphoric acids have been studied. A convenient method for the preparation of phosphinic acids is the reactions of ethyl diethoxymethylphosphonite with ethyl acetamidomethylenemalonate and ethyl 2-acetamidoacrylate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 2066–2069, August, 1996.     

Synthesis of phosphinic and phosphonic analogs of aromatic amino acids

The reaction of aryl and aralkyl aldoximes with hypophosphorous acid resulted in aminophosphinic acids, which were oxidized into the corresponding aminophosphonic acids. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 137–140, January, 1997.     

Synthesis of phosphinic analogs of sulfur-containing amino acids

Phosphinic analogs of the key compounds of the metabolism of methionine were synthesized. The compounds obtained were selectively oxidized either at the phosphinic group or at the sulfur-containing fragment. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1360–1363, July, 1999.     

含氨基的金刚烷桥头二取代化合物合成研究

采用金刚烷甲酸为原料,经溴代、叠氮化、库尔提斯重排、水解等四步反应合成了3-氨基-1-金刚烷醇(糖尿病药物中间体),总收率为34%;以金刚烷甲酸为原料,在无需卤素取代下,通过里特反应、水解反应合成了3-氨基-1-金刚烷甲酸盐酸盐(抗肿瘤药物中间体),总收率为73%.采用元素分析、红外光谱、质谱、核磁共振谱等手段对两种产物的进行了结构鉴定,分别提出了可能的反应机理.     

Synthesis of derivatives of 2-hydroxyimino- and 2-alkoxyimino-3-(acylhydrazono)butanoic acids

Esters andN-methylamides of 2-hydroxyimino- and 2-alkoxyimino-3-(acylhydrazono)-butanoic acids were synthesized by condensation of acyl hydrazines with the corresponding alkyl 2-hydroxyimino- and 2-alkoxyimino-3-oxobutanoates andN-methyl-2-methoxyimino-3-oxobutanamide. The compounds obtained are analogs of strobilurins, fungicidal antibiotics. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 499–504, March, 1999.     

New phosphonic analogs of aspartic and glutamic acid by aminoalkylation of trivalent phosphorus chlorides with ethyl acetyloacetate or ethyl levulinate and benzyl carbamate

Preparation of the phosphonic analogs of -methylaspartic (4 a–d), glutamic (7 a–b) and -methylpyroglutamic (5 a–b) acids by aminoalkylation of trivalent phosphorus chlorides with ethyl esters of oxoalkyloacids and benzyl carbamate is described. The phosphonic analogs of pyroglutamic acid (8 a–b) was obtained by the cyclization of the corresponding esters (9 a–b). The stability of the phosphonic analogs of pyroglutamic acid in acidic and alkaline media was also studied.

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Die Herstellung von neuen Phosphonanalogen der Asparagin- und Glutaminsäure in der Reaktion von trivalenten Phosphorchloriden mit Ethyl-acetyloacetat oder Ethyl-lävulinat bzw. Benzylcarbaminat

Zusammenfassung Es wurde die Darstellung der Phosphonanalogen der -Methylasparaginsäure (4 a–d), Glutamin- (7 a–b) und -Methylpyroglutaminsäure (5 a–b) in der Reaktion der trivalenten Phosphorchloride und der Oxoalkansäureethylester sowie des Benzylcarbaminats beschrieben. In der Ringschlußreaktion der Ester (9 a–b) erhält man Phosphonanaloge der Pyroglutaminsäure. Die Stabilität der Analogen der Pyroglutaminsäure wurde in sauren und alkalischen Medien geprüft.

     

二茂铁基Tamoxifen类似物的合成、结构与性质

合成了一系列二茂铁基Tamoxifen类似物并作了初步生化试验(RBA试验),研究了代表化合物二茂铁基羟基Tamoxifen的晶体结构和顺-反异构化。     

Synthesis of mono- and polyhydroxylated cyclobutane nucleoside analogs

Enantiomerically enriched cyclobutene compounds 13 and 24 are good precursors of several cyclobutane nucleoside analogs. The synthetic ways involve, in the key step, either hydroboration or dihydroxylation.     

Enantiomeric separation of α-phenylethylamine and its analogs by mixed chiral and achiral stationary phase

A mixed stationary phase of modified β-cyclodextrin, 2,6-di-O-butyl-3-O-butyryl-β-cyclodextrin (phase A), and SE-54 (phase B) was used for enantiomeric separation of α-phenylethylami-ne, o,m,p-methyl and o,m,p-methoxy-substituted analogs. The composition of mixed phase was selected by comparison of each calculated amin(= (γm,i+1)/(γm,i))> the relative retention values of the most adjacent peaks, and γm,last, the relative retention values of the last eluting peak at each preselected ratio. Values of γm,i,α calculated by derived equations were in good agreement with the experimental results obtained with two specified mixed phases. All solutes investigated were almost baseline separated at a predicted composition of phase A and phase B in a single run within 18 minutes.     

Synthesis and conformation studies of rubiyunnanin B analogs

Five new analogs 4–8 of rubiyunnanin B (1), mainly modified on the tetrapeptide subunit, were synthesized. These agents 4–8 were substituted d-Ala-l-Ala-l-Tyr(OMe)-l-Ala, d-Ala-l-Ala-l-Phe-l-Ala, d-Ala-l-Ala-l-Try-l-Ala, d-Ala-l-Ala-l-Pro-l-Ala, and d-Ala-l-Ala-l-Ala for the d-Ala-l-Ala-l-N-Me-Tyr(OMe)-l-Ala tetrapeptide subunit. Unlike the natural product, the synthetic agents 4–8 adopt only a single solution conformation, and the central peptide bond in the cyclodityrosine subunit of compounds 4–8 adopt trans stereochemistry. Cytotoxic activities of analogs 4–8 against three human cancer cell lines including A549, BGC-823, and HeLa were evaluated and all the five synthesized peptides exhibited no effects against the test cell lines. These compounds were also evaluated for their antiinsulin resistance and insulin sensitizing activities and none of them showed activity in these assays.     

革兰氏阴性细菌群体感应信号分子AHL结构类似物的合成及活性研究

基于组氨酸的结构基础,以82.7～85.2％的产率合成了4种N-酰基高丝氨酸内酯(AHL)的结构类似物(His-7,His-8,His-10和His-12),经IR、1 H NMR、13 C NMR和MS确认了产物的结构.将四种化合物与紫色色杆菌共培养考察其对革兰氏阴性细菌群体感应系统的影响.结果表明:His-7对紫色...     

Reaction of Barbituric, 2-Thiobarbituric Acids and Their Derivatives with 2-Carboxybenzaldehyde and Opianic Acid: Synthesis and Tautomerism of 5-(3'-Oxo-1',3'-dihydroisobenzofuran-1'-yl)barbituric Acids and Their 2-Thio Analogs

The reaction of barbituric, N-alkylbarbituric acids, and their 2-thio analogs with carboxybenzaldehyde and 2-carboxy-3,4-dimethoxybenzaldehyde leads to the formation of the corresponding 5-(3'-oxo-1',3'-dihydroisobenzofuran-1'-yl)barbituric and 2-thiobarbituric acids, the structures of which were studied by ¹H and ¹³C NMR spectroscopy and mass spectrometry. In DMSO the derivatives of barbituric acid exist in the form of mixtures of the ketone and enol tautomers, while their 2-thio analogs exist in the enol form. In chloroform the tautomeric equilibrium is displaced fully toward the ketone form.     

姜黄素类似物的合成及其清除自由基的研究

姜黄素(见图1)为中药姜黄的主要成分,是一种黄色色素。研究报道姜黄素具有抗氧化、抗炎、抗病毒、抗癌等生物活性[1-4]。本文通过芳香醛和环己酮催化缩合反应合成了一系列姜黄素类似物(见图2),研究了它们抗自由基的活性。图1姜黄素的化学结构F ig.1 Chem ical structure of cur     

Synthesis and Oxidation of 1,3-Diamino- and 1-Amino-3-azidoindazoles

The amination of 3-amino- and 3-azidoindazoles by hydroxylamine-O-sulfonic acid in an alkaline medium yields previously unreported 1,3-diamino- and 1-amino-3-azidoindazoles. These products undergo slow autoxidation in chloroform solution to give 4-aminobenzo-1,2,3-triazine. The action of formic or acetic acid on 3-amino-1-benzylideneaminoindazole leads to recyclization and formation of 3-amino-2-benzylindazole, which is also formed in the catalytic hydrogenation of 1-benzylamino-3-nitro- and 1-benzylideneamino-3-nitroindazoles.     

Synthesis and coordination chemistry of fluorinated phosphonic acids

Phosphonic acids [(HO)₂P(O)C₂H₄C_nF_2n+1] (n = 4, 6) and [(HO)₂P(O)C₆H₄-4-C_nF_2n+1] (n = 0, 1, 6) have been prepared in good yields. Deprotonation and reaction with cis-[PtCl₂(PPh₃)₂] affords fluorinated platinum complexes which have been characterised by elemental analysis, mass spectrometry, IR and NMR spectroscopies. The structures of [Pt{O₂P(O)C₆H₄-4-F}(PPh₃)₂], [Pt{O₂P(O)C₆H₄-4-CF₃}(PPh₃)₂] and [Pt{O₂P(O)C₂H₄C₆F₁₃}(PPh₃)₂] have been determined by single crystal X-ray diffraction.     

Synthetic analogs of naturally occurring flavolignans. XI. Reaction of synthetic flavone analogs with hydrazine hydrate and its derivatives

Reactions of 1,3-benzodioxane and 1,4-benzodioxane analogs of flavones with hydrazine derivatives are studied. The hydrazines recyclize the new flavones into 3,5-diarylpyrazoles. Their PMR spectra confirm their structures.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–41, January–February, 2000.     

Synthesis,Characterization and Structure of Chiral Amino Acids and Their Corresponding Amino Alcohols with Camphoric Backbone

1 INTRODUCTION Chiral amino acids and their versatile derivatives are very useful compounds in many fields[1]. In com- parison with well-documented chiral α and β amino acids and amino alcohols, the studies of chiral γ, δ… ω amino acids and amino alcohols deserve more attention. For example, there have been numerous reports on versatile functions of γ aminobutyric acid (GABA) produced from L-glutamic acid in the presence of L-glutamate decarboxylase (GAD)[2]. However, the stereo…     

Synthesis and antitubercular activity of tricyclic analogs of puupehenone

Tricyclic analogs 2a and 8 were prepared by four-step routes. The key step was an intermolecular hetero Diels-Alder reaction involving a quinone methide.     

3-三氟-2-羟基/氨基-1-氟代丙基膦酸酯的合成

Reaction of diethyl 2,2-difluoro-3-（a-methylbenzyl）imino-4,4,4-trifluoropropanephosphonate （3） with triethylamine afforded a mixture of normal [1,3]-proton shift reaction product 5 and its HF-eliminated compound 6Z in 1 ： 1 ratio. Upon hydrolysis, this reaction mixture gave solely 1,3,3,3-tetrafluoro-2-dioxypropanephosphonate （9）. Reaction of 3 with DBU provided only 6, in which the ratio of E/Z forms was dependent on the reaction conditions. Aqueous hydrolysis of 6 led to 9. Catalytic hydrogenation and hydrogenolysis of 6 gave geometric isomers of 11 as expected. The reaction mechanism involved was discussed.     

Exploring the N-terminus region: Synthesis,bioactivity and 3D-QSAR of allatostatin analogs as novel insect growth regulators

Two series of peptidomimetic analogs with different substituents on the N-terminus region were designed and synthesized to explore the relationship between the structure and the inhibition activity in vitro. In addition, 3D-QSAR study was performed to highlight the structural requirements of AST analogs.