Reaction of Acylpyruvic Acids and Their Esters with N-(2-Aminophenyl)acetamide

Russian Journal of Organic Chemistry - Acylpyruvic acids and their esters regioselectively reacted with N-(2-aminophenyl)acetamide to give acyclic enamines, substituted...     

2-Substituted 2-Propenoic Acid Esters via Reaction of a Masked Acrylate Ester with Carbonyl Compounds

β-Amino ester enolate reacts readily with selected aldehydes and ketones. Deprotection via the N-oxide provides good yields of the 2-substituted acrylate ester.     

（甲基）丙烯酸多环脂基酯单体及其聚合物

介绍部分(甲基)丙烯酸多环脂基酯及其聚合物的合成、性质与用途。     

Antifungal Activity of Salicylanilides and Their Esters with 4-(Trifluoromethyl)benzoic Acid

Searching for novel antimicrobial agents still represents a current topic in medicinal chemistry. In this study, the synthesis and analytical data of eighteen salicylanilide esters with 4-(trifluoromethyl)benzoic acid are presented. They were assayed in vitro as potential antimycotic agents against eight fungal strains, along with their parent salicylanilides. The antifungal activity of the presented derivatives was not uniform and moulds showed a higher susceptibility with minimum inhibitory concentrations (MIC) 3 0.49 μmol/L than yeasts (MIC 3 1.95 μmol/L). However, it was not possible to evaluate a range of 4-(trifluoromethyl)benzoates due to their low solubility. In general, the most active salicylanilide was N-(4-bromophenyl)-4-chloro-2-hydroxybenzamide and among esters, the corresponding 2-(4-bromophenylcarbamoyl)-5-chlorophenyl 4-(trifluoromethyl) benzoate exhibited the lowest MIC of 0.49 μmol/L. However, the esterification of salicylanilides by 4-(trifluoromethyl)benzoic acid did not result unequivocally in a higher antifungal potency.     

含P_H键苯并磷杂环化合物与醛反应的研究

利用含P_H键苯并磷杂环化合物与醛的反应,设计合成了新的A2羟基膦酸衍生化喹唑啉酮含磷类似物2或Ò,并研究了含P_C_O结构的2或Ò转化为含P_O_C结构的3或Ó的重排反应,目标化合物的结构经NMR,IR,MS和元素分析证实.结合NMR数据,探讨了化合物2因具有C^*和P^*两个手性中心而产生的非对映异构现象及其氢谱特征.对所合成的化合物进行了初步生物活性测试,发现部分化合物具有很好的抗植物病原真菌(苹果斑点落叶病菌)作用和一定的人体疱疹病毒抑制活性.     

S-2-(苄氧羰基)氨基-6-(三苯甲基)巯基-正己酸甲酯的简便合成

以L-赖氨酸为原料研究了新化合物S-2-（苄氧羰基）氨基-6-（三苯甲基）巯基．正己酸甲酯的合成,合成的总收率为27％．该方法简便高效,同时可作为半胱氨酸同系物的通用合成方法．     

Iron-Catalyzed Cleavage Reaction of Keto Acids with Aliphatic Aldehydes for the Synthesis of Ketones and Ketone Esters

The radical–radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical–radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphatic aldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained instead of ketones. The gram-scale preparation of aryl ketone through this strategy was easily achieved by using only 3 mol % of the iron catalyst. As a proof-of-concept, the bioactive molecule flurprimidol was synthesized in two steps by using this strategy.     

丙二腈及氰乙酸酯参与的3-脱氢莽草酸甲酯缩合-芳构化-环合串联反应

3-脱氢莽草酸甲酯与丙二腈、氰乙酸乙酯及氰乙酸甲酯等活性亚甲基化合物在一定条件下发生缩合、芳构化及环合反应,可方便地构建C—C键并得到多取代的2-氨基苯并呋喃类化合物(3a~3e,4a和4b),其中化合物3a中的氰基和甲氧羰基可分别进行选择性水解.该方法具有原料易得、条件温和、操作简单及收率高等优点,为可再生生物质资源莽草酸的多样化转化和利用提供了新思路.     

Convenient and One-pot Method for Synthesis of the Amino-methylene Bisphosphonic Acid Derivatives from Aldehydes

Bisphosphonic acids and their ester derivatives, carbon analogues of inorganic pyrophos- phate, are the most important organophosphorus compounds and exhibit unique physical and chemical properties in interaction with the alkaline earth cations or heavy m…     

A Convenient Synthesis of the Monodimethylacetal of Fumaraldehydic Acid and the Corresponding Chiral Esters

A short synthesis of the monodimethylacetal of fumaraldehydic acid 3 and the corresponding chiral esters 4 and 5 is reported. The key step is the oxidation of the fumaraldehyde monodimethylacetal 2.     

三乙烯二胺促进炔酸聚乙二醇酯与苯酚的加成反应研究

以单甲氧基聚乙二醇和2-丁炔酸为起始原料,制得2-丁炔酸聚乙二醇酯（1）;以异丙醇为溶剂,三乙烯二胺（DABCO）为催化剂,1与苯酚经Michael加成反应合成了苯酚的聚乙二醇化产物（2）,其结构经¹H NMR和FT-IR确证。在最优反应条件［n（苯酚）:n（1）: n（DABCO）=20:1:20,异丙醇0.5 mL,于室温反应12 h］下,2产率99%。     

L-Amino Acid Esters Studies: Part II: Synthesis of N-(Dimethoxy/3,5-Diacetoxybenzoyl)-L-Amino Acid Hydrazides and their Reactions with Aldehydes and Ketones

The synthesis of N-(dimethoxy and 3, 5-diacetoxybenzoyl) -L- amino acid hydrazides, and their reactions with some aldehydes and ketones are described.     

杂多酸(盐)催化合成双季戊四醇六正戊酸单己二酸酯的研究

研究了以杂多酸 (盐 )为催化剂 ,合成双季戊四醇六正戊酸单己二酸酯的优化条件 :催化剂为反应物的 0 .8% ,季戊四醇∶己二酸∶正戊酸为1∶0 .3∶0 .5(mol) ,反应在回流温度下进行 3 .0h ,酯的产率在 93 %以上。     

Microwave Synthesis of Copolymers Based on Itaconic Acid Moiety and Their Utility for Scavenging of Copper (II) and Lead (II)

We report here the preparation of the two copolymers, itaconic acid-methyl methacrylate and itaconic acid-acrylamide, in different ratios using microwave irradiation in the presence of azobisisobutyronitrile (AIBN) as initiator and 2-butanone as a solvent. All the prepared copolymers were characterized by different techniques; FT-IR, thermal analysis and elemental microanalysis. The thermal stability property of the prepared copolymers correlated with the changing of the itaconic acid ratio, as the ratio of itaconic acid increased, the crystallinity of the copolymer decreases. The itaconic acid-based copolymers also showed a good scavenging behavior in alkaline media for Cu (II) and Pb (II). The chelation behavior of both Cu (II) and Pb (II) complexes were checked using FT-IR, thermogravimetric analysis (TGA), and differential scanning calorimetery (DSC).     

A Convenient Method for the Large Scale Preparation of (E)-4-Oxo-2-Butenoic Acid Ethyl Ester

A one step synthesis of (E)-4-oxo-2-butenoic acid ethyl ester via the reaction of ethyl 2-ethoxy-2-hydroxyacetate and (formylmethylene)triphenylphosphorane is described. The method proceeds in good yield on a molar scale.     

Synthesis of Substituted 1,2-Dihydropyridines by the Reaction of (Ethoxymethylidene)cyanoacetic Ester and Arylamides of Acetoacetic Acid

Russian Journal of Organic Chemistry - The reaction of (ethoxymethylidene)cyanoacetic ester with arylamides of acetoacetic acid proceeds under heating in the presence of triethylamine or at room...     

Studies on the Wittig Reaction (V) Trans Stereoselectivity in the Reaction of Benzylidene Alkyl Diphenylphosphorane and Aldehydes

Abstract

In previous papers, we reported the E-selectivity in the Wittig reaction of phosphorus ylid of the general formula Ph₂R′CH₂P=CHR (R=alkenyl; R′=H, alkenyl) and aldehydes. This continuing research for the stereochemistry of diphenylphosphorane in the title reaction of Ph₂R′CH₂P=CHR and R″CHO, where R=Ph, R′=H,Ph and R″=Ph,p-substituted phenyl, has led to thosimilar results. However, the E-selectivity is dependent on the ylid structure, reaction condition and the nature of the substituents on the aromatic ring. Generally the effect is stronger with benzyl diphenylphosphorane(R=H), the proportion of E olefin is produced in a larger quantity in salt-free condition than in the salt-containing medium, and the aromatic aldehyde bearing an electronwithdrawing group on the ring gives a higher E/Z ratio. Moreover, we also found that the logarithms of the E/Z ratio of the substituted stilbene products are linear with the σ constant of the substituents of the aromatic aldehydes: log E/Z=aσ+ b