Expedient Synthesis of 6-Aryl Derivatives of 3,4-Dihydro-1,4,4a,6a-tetraaza-benzo[a]fluoren-2-one: A New Heterocyclic Framework

3,4-Dihydro-1,4,4a,6a-tetraaza-benzo[a]fluoren-2-one, a new tetracyclic heterocyclic framework, is designed through a simple and convenient synthetic sequence. Its 6-aryl derivatives are synthesized starting from 1H-indole-2-carboxylic acid. The reaction of differently substituted phenacyl bromides with 1H-indole-2-carboxylic acid and POCl₃-mediated cyclization of the resultant 1H-indole-2-carboxylic acid phenacyl ester provided 2-oxa-4a-aza-fluoren-1-one, and its sequential reaction with hydrazine and 2-chloro-acetamide furnished the desired new heterocyclic compounds 7a–f.     

1,2,4,6-四芳基-1,4-二氢吡嗪的合成

吡嗪类化合物是许多具有生物活性的分子的结构单元 ,也可以作为生物试剂 ,特别是多芳基1 ,4 二氢吡嗪类化合物 1本身就可以作为食品香料和染料[1～ 6] 。对于这一类具有生理活性的化合物 ,至今还少有报道。Ｆｏｕｒｒｅｙ .Ｊ[3] 等人曾经在相转移催化的条件下 ,利用固相反应合成了这类化合物。但是一般反应时间很长、步骤多 ,总产率不尽人意 ,一般在 1 0 %左右 ,本文报道一种一锅法合成这类化合物的新方法。合成路线为 :1　实验1 .1　仪器与试剂ＡＺ 30 0ＭＨｚ1 ＨＮＭＲ仪 ,ＴＭＳ作内标 ;Ｆｉｎｉｇａｎ82 30型质谱仪 ;Ｓｈｉｍａｄｚｕ…     

Updates on synthesis and biological activities of 1,3,4-oxadiazole: A review

The new era of heterocyclic moieties which are developed in the decades plays a very important role in the treatment of various diseases. Among them are 1,3,4-oxadiazoles, a heterocyclic five-membered ring which plays an vital role in the development of newer medicinal compounds for treating various biological activities, such as proliferation of cells, tuberculosis, allergy, viral diseases, etc. The present review will summarize the various synthetic approaches which will be correlated with the biological activities so that the information in future may be used by many researches to give a path breaking lead in the field of medicinal chemistry.     

膦酰基杂环化合物的合成方法研究进展

综述了利用含膦酰基的开链前体合成子通过环合成来获得膦酰基杂环化合物的各种方法。     

The synthesis of N-containing heterocyclic compounds catalyzed by copper/L-proline

N-containing heterocyclic compounds are one of the most important motifs prevalent in various bioactive natural products and pharmaceuticals. Given the significance of N-containing heterocyclic compounds, various synthetic strategies have been developed. Copper/ligand (abbreviated as [CuL])-catalyzed cascade reaction is a powerful and efficient tool for the construction of N-containing heterocyclic compounds. L-proline is one universal ligand and has been utilized in the copper-catalyzed reactions. In this review, copper/L-proline-catalyzed tandem reaction to synthesize the five- and six-membered compounds is emphatically introduced. By comparing the yields in the presence and absence of the ligand, the importance of L-proline is recorded. Moreover, the function of L-proline is expounded on the basis of the reaction mechanism from original article.     

Review of Synthesis of Multispiro Heterocyclic Compounds from Isatin

Because of its various biological activities, isatin plays important roles in organic chemistry. The C-3 carbonyl group of the isatin possesses very high reactivity and thus isatin possesses many diverse applications in organic synthesis. This carbonyl group reacts like a prochiral center. For the organic synthetic chemist, the conception of a spiroheterocyclic building block has always been interesting, as it often requires synthetic design based on specific strategies. This review summarizes the synthesis of various multispiro heterocyclic compounds by using isatin through 1,3-dipolar cycloaddition reactions and multicomponent reactions.     

过渡金属催化合成含氮杂环化合物的研究进展

含氮杂环化合物是一类非常重要的有机杂环化合物,也是有机合成化学的研究热点之一。本文首先简要介绍了含氮杂环化合物在天然产物、合成药物和功能材料中的分布及其广泛应用;然后以不同过渡金属催化剂为线索,按照时间由远至近的顺序分别概述了Pd、Ag、Fe、Ni、Zn、Cu等六类过渡金属催化剂在合成五、六元含氮杂环化合物方面的研究进展,对反应条件、反应特征进行了概括;最后对含氮杂环化合物合成领域的过渡金属催化剂的整体发展趋势进行了归纳总结。     

(N‐heterocyclic carbene)PdCl(N‐heterocyclic carboxylate) complexes: Synthesis and catalytic activities towards arylation of benzoxazoles with aryl halides

A series of N‐heterocyclic carboxylate‐stabilized N‐heterocyclic carbene palladium complexes have been synthesized and fully characterized. The solid‐state structures indicate that each of the palladium centers is coordinated by an N‐heterocyclic carbene, a chloride and a bidentate N,O‐donor N‐heterocyclic carboxylate ligand. The catalytic performance of the complexes was screened and the results revealed that the complexes exhibit moderate to high catalytic activities for the direct C─H bond arylation of benzoxazoles with aryl bromides.     

Synthesis and Properties of 1,3-Diaryl-5,6-dihydro-8H-imidazo[2,1-c]-1,4-oxazinium Bromides

It has been established that the condensation of 3-(4-methoxyphenylamino)-5,6-dihydro-2H-1,4-oxazine with substituted phenacyl bromides occurs at the exocyclic nitrogen atom with formation of 3-aryl-3-hydroxy-1-(4-methoxyphenyl)-2,5,6,8-tetrahydro-3H-imidazo[2,1-c]-1,4-oxazinium bromides. By treatment of the latter with acetic anhydride 3-aryl-1-(4-methoxyphenyl)-5,6-dihydro-8H-imidazo[2,1-c]-1,4-oxazinium bromides are formed. The structures of the compounds synthesized were determined via ¹H NMR spectroscopy and X-ray diffraction.     

系列烯基化芳香杂环化合物的合成及结构表征

报道了一个简单、 高选择性合成烯基化芳香杂环化合物的反应体系. 在钯的催化作用下, 以乙酸/乙酸酐或四氢呋喃为溶剂, 芳香杂环化合物与烯基化试剂进行交叉脱氢偶联, 合成了系列具有潜在光学活性的烯基化芳香杂环化合物, 确定了最佳反应条件. 采用紫外光谱、 核磁共振氢谱和X射线单晶衍射对目标化合物进行了表征, 并对反应机理进行了探讨.     

Access to Spiro and Fused Indole Derivatives from α,β‐Unsaturated Aldehydes Enabled by N‐Heterocyclic Carbene Catalysis

Spiro and fused indoles are attractive heterocyclic compounds with broad and promising activities in various therapeutic fields, and thus, have become the synthetic targets of organic chemists. In this account, we describe our recent progress in the synthesis of a series of spiro and fused indole derivatives through N‐heterocyclic carbene (NHC)‐catalyzed annulations of diverse NHC‐bound intermediates derived from α,β‐unsaturated aldehydes. Particularly, the novel synthesized isatin‐derived α‐bromoenals may be used as versatile 1,3‐biselectrophile synthons for combination with a range of bisnucleophiles for potentially divergent syntheses of skeletally diverse spirooxindoles in the future.     

杂环化合物氮氧化反应研究的新进展

杂环化合物的N-氧化物是一类重要的有机中间体, 也可以直接用作催化剂、炸药等. 综述了杂环化合物N-氧化反应的最新进展, 包括单氮、双氮和多氮杂环化合物的N-氧化反应, 以及在形成N→O基团的同时合成目标产物的反应, 并重点讨论了具有复杂结构的杂环化合物N-氧化反应.     

Synthetic Strategies for Fused Benzothiazoles: Past,Present, and Future

Benzothiazole is used as a building block in organic synthesis, which serves as a key template for the development of various therapeutic agents and shows a wide spectrum of activities. The attractive application of benzothiazole in organic synthesis is undoubtedly due to the highly reactive C-2 amino group, which is responsible for the change in its bioactivity. The construction of a poly-heterocyclic compound with the fused hetero-systems has attracted increasing attention because of the diverse range of potential therapeutic activities. Significant efforts have been undertaken to exploit different synthetic routes to these compounds. This article gives a comprehensive account of the synthetic utility of benzothiazole employed in the design and synthesis of different types of compounds containing fused heterocyclic rings with greater emphasis on recent literature.     

Heterocyclic Chemistry Applied to the Design of N-Acyl Homoserine Lactone Analogues as Bacterial Quorum Sensing Signals Mimics

N-acyl homoserine lactones (AHLs) are small signaling molecules used by many Gram-negative bacteria for coordinating their behavior as a function of their population density. This process, based on the biosynthesis and the sensing of such molecular signals, and referred to as Quorum Sensing (QS), regulates various gene expressions, including growth, virulence, biofilms formation, and toxin production. Considering the role of QS in bacterial pathogenicity, its modulation appears as a possible complementary approach in antibacterial strategies. Analogues and mimics of AHLs are therefore biologically relevant targets, including several families in which heterocyclic chemistry provides a strategic contribution in the molecular design and the synthetic approach. AHLs consist of three main sections, the homoserine lactone ring, the central amide group, and the side chain, which can vary in length and level of oxygenation. The purpose of this review is to summarize the contribution of heterocyclic chemistry in the design of AHLs analogues, insisting on the way heterocyclic building blocks can serve as replacements of the lactone moiety, as a bioisostere for the amide group, or as an additional pattern appended to the side chain. A few non-AHL-related heterocyclic compounds with AHL-like QS activity are also mentioned.     

Synthesis,In Vitro α-Amylase Activity,and Molecular Docking Study of New Benzimidazole Derivatives

Russian Journal of Organic Chemistry - New benzimidazole derivatives were synthesized by reacting substituted phenacyl bromides with 1H-benzimidazole-2-thiols. The synthesized compounds were...     

2,3-位稠杂环喹唑啉酮类化合物的合成研究进展

2,3-位稠环喹唑啉酮类化合物由于具有多种优良的生物和生理活性而广泛应用于药物领域,其合成方法是目前药物研究的热点领域之一.本文主要介绍了包括以2-氨基苯甲酸类化合物、2-氨基苯甲酸甲酯类化合物、靛红酸酐类化合物、喹唑啉酮类化合物等为原料合成2,3-位稠环喹唑啉酮类化合物的方法,并对这些方法进行了简单的评述.     

无溶剂反应在杂环合成中的应用进展

杂环化合物在药物和农药领域具有多种优良的生物活性,其合成方法是目前药物和农药研究的热点领域之一.以绿色合成为主题,介绍了无溶剂杂环有机合成在产率高、选择性好、操作简便、成本低及环境友好等绿色化学方面的优点,综述了近四年无溶剂反应在杂环合成方面研究的最新进展.     

THE CHEMISTRY OF 3-AMINOTHIOACRYLAMIDES; PART II: 3-AMINOTHIOACRYLAMIDES AS USEFUL SYNTHONS IN ORGANIC SYNTHESIS

Abstract

3-Aminothioacrylamides are a class of organic sulfur containing compounds that are easily available and exhibit polyfunctional reaction behaviour. They can be used widely in the synthesis of a variety of heterocyclic and open chain compounds. The synthetic utility of 3-aminothioacrylamides can be further extended if additional functionalities are incorporated.     

Regioselective alkylation of isopropylidene- and cyclohexylidenepropanedinitrile with phenacyl bromides

Alkylation of isopropylidene- and cyclohexylidenepropanedinitrile with phenacyl bromides gave 2,2-bis(2-aryl-2-oxoethyl)propanedinitriles. Direct alkylation of propanedinitrile with phenacyl bromides afforded only 2-(2-aryl-2-oxoethyl)propanedinitriles.     

Pyridine Scaffolds,Phenols and Derivatives of Azo Moiety: Current Therapeutic Perspectives

Synthetic heterocyclic compounds have incredible potential against different diseases; pyridines, phenolic compounds and the derivatives of azo moiety have shown excellent antimicrobial, antiviral, antidiabetic, anti-melanogenic, anti-ulcer, anticancer, anti-mycobacterial, anti-inflammatory, DNA binding and chemosensing activities. In the present review, the above-mentioned activities of the nitrogen-containing heterocyclic compounds (pyridines), hydroxyl (phenols) and azo derivatives are discussed with reference to the minimum inhibitory concentration and structure–activity relationship, which clearly indicate that the presence of nitrogen in the phenyl ring; in addition, the hydroxyl substituent and the incorporation of a diazo group is crucial for the improved efficacies of the compounds in probing different diseases. The comparison was made with the reported drugs and new synthetic derivatives that showed recent therapeutic perspectives made in the last five years.