Synthesis of Ethyl 2-Hydroxy-3-[aryl(2-naphthylamino)methyl]-2-cyclopentenecarboxylates and Ethyl 3-Arylmethylene-2-(2-naphthylamino)-1-cyclopentenecarboxylates

Condensation of N-arylmethylene-2-naphthylamines with ethyl 2-oxocycopentanecarboxylate in the presence of HCl or CH₃COOH yields ethyl 2-hydroxy-3-[aryl(2-naphthylamino)methyl]-2-cyclopentenecarboxylates and ethyl 3-arylmethylene-2-(2-naphthylamino)-1-cyclopentenecarboxylates, respectively.     

Functional Derivatives of Ethyl 4-(Chloromethyl)-2,6-dimethylpyridine-3-carboxylate

The condensation of ethyl 4-(chloromethyl)-2,6-dimethylpyridine-3-carboxylate with substituted phenols in ethanol in the presence of potassium carbonate afforded the corresponding aryl pyridin-4-ylmethyl ethers. Analogous condensation with substituted anilines gave 2-aryl-4,6-dimethyl-1,2-dihydropyrrolo[3,4-c]- pyridin-3-ones. Esters containing 1,2-azole fragments were synthesized by acylation of hydroxymethylsubstituted ethers with 5-arylisoxazole- and 4,5-dichloroisothiazole-3-carbonyl chlorides.     

(S)-2-乙氧基-3-(4-羟基苯基)丙酸乙酯的合成

(S)-2-乙氧基-3-(4-羟基苯基)丙酸乙酯的合成;二乙氧基乙酸乙酯;Horner Wadswordth Emmons反应;催化氢化;化学拆分;（S） 乙氧基（羟基苯基）     

重组大肠杆菌细胞不对称还原4-氯乙酰乙酸乙酯合成(R)-(+)-4-氯-3-羟基丁酸乙酯

 从赭色掷孢酵母(Sporobolomyces salmonicolor ZJU0105)中克隆出NADPH依赖型醛基还原酶基因,构建了重组大肠杆菌E.coli BL21(pET28-ALR0105), 该工程菌可以高效地表达醛基还原酶. 将重组细胞用于催化4-氯乙酰乙酸乙酯不对称还原,合成出具有光学活性的(R)-(+)-4-氯-3-羟基丁酸乙酯. 实验发现,在加入适量辅酶及辅酶再生酶的条件下,利用重组细胞催化还原反应可以获得比使用赭色掷孢酵母更高的转化率、产率和ee值,得到了几乎是光学纯的(R)-(+)-型产物,从而解决了酵母细胞催化此类反应ee值较低的问题. 考察了辅酶及共底物的添加、底物和产物的浓度、pH值、温度以及菌体密度等因素对还原反应的影响. 结果表明,不对称还原反应必须在辅酶NADPH和辅酶再生酶系及共底物葡萄糖的参与下进行; 底物和高浓度的产物对还原反应有一定的抑制作用; 当pH＞6.0时,反应的转化率及产率都显著降低; 高密度重组细胞可以减小底物的抑制作用.     

Radical copolymerization of γ-methylene-Δα,β-butenolide derivative: Ethyl(E)-5-oxo-2,5-dihydrofuran-2-ylidene-acetate

Radical polymerications including co- and terpolymerizations of a γ-methylene-Δ^α,β-butenolide derivative, ethyl (E)-5-oxo-2,5-dihydrofuran-2-ylideneacetate(EODY) was investigated. The monomer had no homopolymerizability but copolymerized with styrene (ST) and 1,3-cyclohexadiene to yield alternating copolymers. From IR and ¹H-NMR spectra of the copolymers, the 1,4-addition was confirmed to exclusively occur for the conjugated double bond of EODY. Terpolymerization for the system involving an acceptor monomer such as maleic anhydride, α-chloromaleic anhydride, or 7,7,8,8-tetracyanoquinodimethane in addition to ST and EODY gave the terpolymer containing about 50 mol% of ST, in spite of a high fraction of ST in the feed. It was inferred that such an apparent behavior of EODY as an acceptor monomer could be due to a resonance-stabilization of the propagating radical having EODY as a terminal unit, which is also responsible for the poor yields of the copolymers and terpolymers.     

Synthesis of 3(5)-(Nitroamino)-1,2,4-triazol-5(3)-carboxylic Acid and Its Ethyl Ester

Russian Journal of Organic Chemistry -     

Synthesis and Some Transformations of Ethyl 5-Alkoxymethyl-3-(2-methyl-3-oxobutyl)-2-oxotetrahydrofuran-3-carboxylates

Michael reaction of ethyl 5-alkoxymethyl-2-oxotetrahydrofuran-3-carboxylates with 3-methyl-3-buten-2-one gave ethyl 5-alkoxymethyl-3-(2-methyl-3-oxobutyl)-2-oxotetrahydrofuran-3-carboxylates. Alkaline hydrolysis of the latter, followed by decarboxylation afforded 5-alkoxymethyl-3-(2-methyl-3-oxobutyl)tetrahydrofuran-2-ones. The bromination of ethyl 5-alkoxymethyl-3-(2-methyl-3-oxobutyl)-2-oxotetrahydrofuran-3-carboxylates provides a convenient method for the preparation of 3-acetyl-8-alkoxymethyl-3-methyl- and 8-alkoxymethyl-3-bromoacetyl-3-methyl-2,7-dioxaspiro[4.4]nonane-1,6-diones in high yields.     

Production of (+)-(S)-Ethyl 3-Hydroxybutyrate and (-)-(R)-Ethyl 3-Hydroxybutyrate by Microbial Reduction of Ethyl Acetoacetate

The production of (S)-ethyl 3-hydroxybutyrate (2) from ethyl acetoacetate (1) in higher yields and with higher optical purity than with the usual procedures was achieved by continuous addition of the substrate 1 and sucrose to an aerated suspension of bakers' yeast. The microbial reduction of 1 by the fungus Geotrichum candidum LINK yields - for the first time - the antipode 3 .     

CTAB透性化酵母细胞生物催化合成(S)-(+)-3-羟基丁酸乙酯

 利用十六烷基三甲基溴化铵(CTAB)透性化啤酒酵母细胞中高活性的脱氢酶,借助于辅助底物乙醇和葡萄糖,对3-羰基丁酸乙酯(EOB)不对称还原合成(S)-(+)-3-羟基丁酸乙酯((S)-(+)-3-EHB)进行了研究. 结果表明,CTAB透性化酵母细胞中的醇脱氢酶和6-磷酸葡萄糖脱氢酶的活性分别比未经处理的酵母细胞高482倍和6.5倍. 在相同条件下,CTAB透性化细胞对EOB的还原比未经处理的酵母细胞快. 细胞浓度对反应有明显影响,当透性化酵母细胞浓度＜90 mg/ml时,(S)-(+)-3-EHB的产率和对映体过量值都较低; 当酵母细胞浓度≥90 mg/ml,在最佳进料速率、最适温度和pH条件下,振摇速度为125 r/min时, (S)-(+)-3-EHB的浓度达到最大值314 mmol/L. 在反应开始的6 h内,(S)-(+)-3-EHB的产率可达94%,对映体过量值≥98%,但24 h后产率和对映体过量值分别降低到85%和91%.     

合成3-(2-吡啶氨基)丙酸乙酯的工艺改进

以2-氨基吡啶(2)和丙烯酸乙酯(3)为起始原料,经一步反应合成了凝血酶因子抑制剂达比加群酯的关键中间体3-(2-吡啶氨基)丙酸乙酯,其结构经1H NMR和ESI-MS确证.最佳反应条件为:2 120 mmol,n(2)∶n(3) =1.00∶1.08,于100℃回流反应24h,收率79.6％.     

Synthesis of Ethyl 5-(Arylcarbamoyl)-6-methyl-2-oxo-1,2-dihydropyridine-3-carboxylates

Russian Journal of Organic Chemistry - A one-step procedure has been developed for the synthesis of previously unknown ethyl 5-(arylcarbamoyl)-6-methyl-2-oxo-1,2-dihydropyridine-3-carboxylates by...     

Synthesis of Ethyl 2-[Alkyl(benzyl)sulfanylmethyl]-3-oxobutanoates and 3H-Pyrazol-3-ones Based Thereon

Russian Journal of Organic Chemistry - Three-component condensation of ethyl acetoacetate with formaldehyde and alkanethiols in the presence of 0.1 equiv of sodium hydroxide afforded ethyl...