2-取代芳基苯并呋喃类化合物生物活性及合成研究进展

综述了近十几年来报道的具有良好生物活性的2-芳基苯并呋喃类化合物, 以及这一类化合物结构骨架的构建与合成方法.     

水介质中N-芳基-N'-(2-苯并呋喃甲酰基)硫脲及1-芳甲酰基-4-(2'-苯并呋喃甲酰基)氨基硫脲的合成

苄基三乙基氯化铵(TEBA)存在的水介质中, 2-苯并呋喃甲酰氯、硫氰酸铵与芳胺或芳甲酰肼在室温条件下经一步反应合成N-芳基-N'-(2-苯并呋喃甲酰基)硫脲或1-芳甲酰基-4-(2'-苯并呋喃甲酰基)氨基硫脲, 其中前者尚未见文献报道. 与其它合成方法相比, 该法操作简单、反应条件温和、环境友好.     

微波促进下1-芳甲酰基-4-（2’-苯并呋喃甲酰基）氨基硫脲及其衍生物的合成

微波辐射条件下，首先由2-苯并呋喃甲酰氯在相转移条件下依次与硫氰酸铵和 芳甲酰肼反应合成了一系列1-芳甲酰基-4-（2’-苯并呋喃甲酰基）氨基硫脲，进 一步在微波辐射的条件下由这些氨基硫脲分别与碘酸钾、醋酸或醋酸汞等试剂作用 高产率地制得了1-芳甲酰基-4-（2’-苯并呋喃甲酰基）氨基脲、2-芳基-5-（2’- 苯并呋喃甲酰胺基）-1，3，4-噻二唑和2-芳基-5-（2’-苯并呋喃甲酰胺基）-1， 3，4-（口恶）二唑。     

微波促进下1-芳甲酰基-4-(2′-苯并呋喃甲酰基)氨基硫脲及其衍生物的合成

微波辐射条件下 ,首先由 2 苯并呋喃甲酰氯在相转移条件下依次与硫氰酸铵和芳甲酰肼反应合成了一系列 1 芳甲酰基 4 ( 2′ 苯并呋喃甲酰基 )氨基硫脲 .进一步在微波辐射的条件下由这些氨基硫脲分别与碘酸钾、醋酸或醋酸汞等试剂作用高产率地制得了 1 芳甲酰基 4 ( 2′ 苯并呋喃甲酰基 )氨基脲、2 芳基 5 ( 2′ 苯并呋喃甲酰胺基 ) 1,3 ,4 噻二唑和 2 芳基 5 ( 2′ 苯并呋喃甲酰胺基 ) 1,3 ,4 二唑 .     

基于钯纳米粒子催化分子内Heck反应合成3-取代苯并呋喃衍生物的研究

发展了一个简单、高效合成3-取代苯并呋喃类化合物的方法.该方法是利用邻溴芳基苯丙烯基醚的分子内Heck反应实现的,简单的钯纳米粒子催化体系对该分子内Heck反应表现出了很高的催化活性,能以高达96%的收率得到一系列3-取代苯并呋喃类化合物.     

微波辐射条件下N-芳基-N''''-(5-苯并呋喃基-1,3,4-噻二唑-2-基)脲的合成

在微波辐射条件下,以2-氨基-5-苯并呋喃基-1,3,4-噻二唑和N-取代三氯乙酰苯胺为原料,在固体氢氧化钠作用下,"一锅法"高产率合成了10种N-(5-苯并呋喃基-1,3,4-噻二唑-2-基)-N'-芳基脲,并通过IR、1H NMR和元素分析表征了目标产物的结构.     

微波辐射条件下N-芳基-N′-(5-苯并呋喃基-1,3,4-噻二唑-2-基)脲的合成

在微波辐射条件下,以2-氨基-5-苯并呋喃基-1,3,4-噻二唑和N-取代三氯乙酰苯胺为原料,在固体氢氧化钠作用下,"一锅法"高产率合成了10种N-(5-苯并呋喃基-1,3,4-噻二唑-2-基)-N'-芳基脲,并通过IR1、H NMR和元素分析表征了目标产物的结构.     

四溴化碳促进下2-(1H-苯并[d]咪唑)-3-芳基丙烯腈的高效合成

2-苯并咪唑-3-芳基丙烯腈衍生物具有广谱的生物活性,同时还是一类重要的合成中间体,在有机合成领域具有广泛的应用.以芳醛和2-氰甲基苯并咪唑为原料,乙醇为溶剂,在四溴化碳促进下,高效合成了2-(1H-苯并[d]咪唑)-3-芳基丙烯腈.反应在回流条件下搅拌5～10 min即可完成,以74%～96%的产率得到目标产物.该方法为2-苯并咪唑-3-芳基丙烯腈衍生物的制备提供了反应条件温和、后处理方便和底物适用范围广的合成策略.     

苯胺促进的异苯并呋喃酮类衍生物的合成

异苯并呋喃酮类化合物广泛存在于自然界中,并具有广泛的生物活性.报道了以邻羧基苯甲醛和不同取代的苯乙酮为原料,苯胺促进的串联反应构建异苯并呋喃酮类骨架结构的合成新方法,该方法具有适用范围广、反应条件温和、高产率和简单易处理等优点,为异苯并呋喃酮类化合物的合成提供了新思路.     

加兰他敏类生物碱的不对称合成研究进展

加兰他敏类生物碱是氢化二苯并呋喃类生物碱的重要组成部分.它们独特的结构、良好的生物活性和前景广阔的药用价值吸引了众多化学家和药物学家的兴趣.其合成难点是其中的含芳基手性全碳季碳的构筑.本综述旨在阐述到目前为止加兰他敏类生物碱的不对称合成方法,根据合成路线中手性季碳的构筑方式分类进行说明,并尝试对每种合成方法进行评述.     

Preparation of 2-, 3-, 4- and 7-(2-alkylcarbamoyl-1-alkylvinyl)benzo[b]furans and their BLT1 and/or BLT2 inhibitory activities

Several 2-alkylcarbamoyl-1-alkylvinylbenzo[b]furans were designed to find a selective leukotriene B4 (LTB4) receptor antagonist. 2-(2-Alkylcarbamoyl-1-alkylvinyl)benzo[b]furans having a substituent group at the 3-position, 4-(2-alkylcarbamoyl-1-methylvinyl)benzo[b]furans having a substituent group at the 3-position, and 7-(2-alkylcarbamoyl-1-methylvinyl)benzo[b]furans and 3-(2-alkylcarbamoyl-1-alkylvinyl)benzo[b]furans were prepared and evaluated for LTB4 receptor (BLT1 and BLT2) inhibitory activities. (E)-3-Amino-4-[2-[2-(3,4-dimethoxyphenyl)ethylcarbamoyl]-1-methylvinyl]benzo[b]furan ((E)-17c) showed potent and selective inhibitory activity for BLT2. On the other hand, (E)-7-(2-diethylcarbamoyl-1-methylvinyl)benzo[b]furan ((E)-27a) showed potent inhibitory activity for both BLT1 and BLT2.     

Syntheses of 3-acetoacetylaminobenzo[b]furan derivatives having cysteinyl leukotriene 2 receptor antagonistic activity

Novel 3-acetoacetylaminobenzo[b]furan derivatives having a modified triene system at the 3-position were synthesized starting with 3-aminobenzo[b]furans. The enol isomers, 3-[(3-hydroxybut-2-enonyl)amino]benzo[b]furans (), of the 3-acetoacetylaminobenzo[b]furans were obtained as stable isomers owing to formation of a hydrogen bonding between the enol hydroxyl group and the amidocarbonyl group. The planarity of the C-2 substituent through the C-3 side chain suggested the existence of a modified conjugational triene system in the enol compound. Cysteinyl leukotriene 1 and 2 receptor antagonistic activities for these compounds were evaluated. 2-(4-Cyanobenzoyl or ethoxycarbonyl)-3-[(2-cyano-3-hydroxybut-2-enonyl)amino]benzo[b]furans (, ) were moderately active.     

Regioselective preparation of benzo[b]furans from phenols and α-bromoketones

In this paper, a fully regiocontrolled synthesis of either 2- and 3-substituted benzo[b]furans is described. Direct reaction between phenols and α-bromoacetophenones in the presence of neutral alumina yields 2-substituted benzo[b]furans with complete regiocontrol. When a basic salt such as potassium carbonate is used, the corresponding 2-oxoether is obtained. Cyclization of these latter compounds promoted by neutral alumina yields the corresponding 3-substituted benzo[b]furans. Using the former method, Moracin M and other analogues can be obtained from commercial sources in two preparative steps. DFT calculations provide reasonable reaction paths to understand the formation of 2-substituted benzo[b]furans.     

Synthesis of 2-arylbenzo[b]furans via copper(I)-catalyzed coupling of o-iodophenols and aryl acetylenes

[reaction: see text] We report a copper(I)-catalyzed procedure for the synthesis of 2-arylbenzo[b]furans. This protocol can be used to synthesize a variety of 2-arylbenzo[b]furans in good to excellent yields. This method can tolerate a variety of functional groups, does not require the use of expensive additives, and is palladium-free.     

Sequential and one-pot reactions of phenols with bromoalkynes for the synthesis of (Z)-2-bromovinyl phenyl ethers and benzo[b]furans

Benzo[b]furans were prepared in one pot based on the addition/palladium-catalyzed C-H bond functionalization of phenols with bromoalkynes. The addition reactions of phenols to bromoalkynes generated (Z)-2-bromovinyl phenyl ethers in high yields with excellent regio- and stereoselectivity. The obtained (Z)-2-bromovinyl phenyl ethers subsequently proceeded by intramolecular cyclization to afford 2-substituted benzo[b]furans in good yields through palladium-catalyzed direct C-H bond functionalizations. It is important to note that the transformation of phenols with bromoalkynes into benzo[b]furans could be carried out in one pot with a simple and efficient tandem procedure.     

Novel and selective palladium-catalyzed annulations of 2-alkynylphenols to form 2-substituted 3-halobenzo[b]furans

[reaction: see text] A novel and selective palladium-catalyzed annulation of 2-alkynylphenols method for the synthesis of 2-substituted 3-halobenzo[b]furans is presented. In the presence of PdX(2), CuX(2), and HEt(3)NX, 2-substituted 3-halobenzo[b]furans were selectively obtained as the major products. The mechanism of the reaction was also discussed.     

An efficient synthesis and substitution of 3-aroyl-2-bromobenzo[b]furans

A convenient method for the synthesis of 2-bromo-3-aroyl-benzo[b]furans from readily accessible precursors has been developed. The 2-bromo group has been employed as a versatile synthetic handle in both palladium-mediated couplings and direct nucleophilic substitutions to give access to a wide range of 2-substituted-3-aroyl-benzo[b]furans.     

Iodine(III)-Mediated Tandem Oxidative Cyclization for Construction of 2-Nitrobenzo[b]furans

Various 3-alkyl-2-nitrobenzo[b]furans were synthesized from common intermediate 2-(2-nitroethyl)phenols via a hypervalent iodine-induced oxidative cyclization, with good to excellent yields. This facile route is able to efficiently functionalize 2-nitrobenzo[b]furans, which are difficult to obtain by classical methods.     

Synthesis and biological activities of novel furo[2,3,4-jk][2]benzazepin-4(3H)-one derivatives

A novel seven-membered lactam formation method has been established by intramolecular ring closure reaction of 4-bromo-(E)-3-[(2-alkylvinyl)carbonylamino]benzo[b]furans under Heck coupling conditions. A number of furo[2,3,4-jk][2]benzazepin-4(3H)-ones, tricyclicbenzo[b]furans, have been prepared by this method and evaluated for their leukotriene B(4) (LTB(4)) receptor and poly(ADP-ribose)polymerase-1 (PARP-1) inhibitory activities.