2-取代苯并噁唑类化合物合成研究进展

2-取代苯并噁唑类化合物在医药、农药以及配位催化等领域有广阔的应用前景,因而其合成方法备受关注.近年来,微波促进、水为介质、无溶剂合成、组合化学以及过渡金属催化等一系列高效、绿色的合成方法在2-取代苯并噁唑类化合物的合成中得到广泛的应用.按照不同的合成原料和合成方法进行分类,综述了近年来2-取代苯并噁唑类化合物合成研究的新进展.     

偏钒酸铵催化合成2-芳基取代苯并噁唑

在偏钒酸铵催化下,以2-氨基苯酚和芳醛为原料、乙醇为溶剂,在室温下合成了一系列2-芳基取代苯并噁唑类化合物.该方法具有操作简便、反应条件温和、产率高等优点.     

苯并双噁唑类聚合物的合成

详细介绍了以4,6-二氨基间苯二酚盐酸盐(DADHB)为原料,采用多聚磷酸法、三甲基硅烷基化法、中间相聚合法、单体成盐法合成聚对苯撑苯并双噁唑(PBO),还有以4,6-二硝基间苯二酚(DNR)为原料,先选择还原制得4-氨基-6-硝基间苯二酚盐酸盐,进而与对甲氧羰基苯甲酰氯进行缩环合获得苯并噁唑化合物,再催化加氢合成AB型PBO新单体2-(对甲氧羰基苯基)-5-氨基-6-羟基苯并噁唑,最后自缩聚反应制备PBO的新路线.另外,本文还介绍了直链烯烃型、直链脂肪烷烃型、稠环芳烃型、联苯取代基型、杂环型、聚醚型等苯并双噁唑类聚合物的合成方法.     

含苯并噁唑的L-酪氨酸衍生物的合成

从L-酪氨酸乙酯出发,经氨基保护、硝化、还原反应制得3-氨基-L-酪氨酸乙酯(4);4与苯甲醛或取代苯甲醛完成环化反应,合成了6个新的含苯并噁唑的L-酪氨酸衍生物,其结构经1H NMR,13C NMR,IR和元素分析表征.     

苯并噁唑类化合物荧光光谱的研究

研究了38种苯并噁唑系列化合物的紫外吸收光谱、荧光发射光谱和荧光量子产率。计算了第一激发单线态辐射和非辐射寿命。结果表明,在苯并噁唑基的苯环上非极性基团取代对辐射和非辐射速率影响不大,但极性基团取代后影响较大。     

噁唑、苯并噁唑及1,3,4-噁二唑硫醚的合成及抗肿瘤活性研究

设计并以噁唑、苯并噁唑及1,3,4-噁二唑硫醇与卤代烃反应合成了14个硫醚类杂环化合物, 其中13个化合物未见文献报道. 目标化合物的结构均通过¹H NMR谱、MS和元素分析进行了表征. 采用MTT [3-(4,5-dimethylthiagol-2-yl)- 2,5-diphenyltetrogolium bromide]法对14个目标化合物进行了体外抗肿瘤活性测定, 结果表明: 在10^－5 mol/L 浓度下, 10个化合物对肿瘤细胞具有抑制活性.     

微波辐射下2-芳基取代苯并噁唑的合成

邻氨基酚和芳香羧酸在微波辐射条件下缩合,合成了4种2-芳基取代苯并噁唑化合物。优化反应条件为：多聚磷酸为催化剂,辐射功率500W,辐射时间4min。     

微波辐射下苯并噁唑基吡啶的合成

在微波辐射条件下,利用邻氨基酚和吡啶羧酸在多聚磷酸中的缩合反应,合成了2种苯并唑基取代吡啶 最佳反应条件为:450W辐射4min 相比于常规反应,反应时间大为缩短且产率令人满意     

2-取代苯并噁唑衍生物的合成及生物活性

疏基苯并噁唑;2-取代苯并噁唑衍生物的合成及生物活性     

2-(2′-苯基丙烯基)苯并噁唑类化合物的合成及晶体结构

合成了11种2-(2′-苯基丙烯基)苯并噁唑类和9种2-(2′-苯基丙烯基)-5-甲基苯并噁唑类化合物。测定了它们的熔点、元素分析、红外光谱及个别衍生物的核磁共振谱和X射线单晶分析,确证了这类化合物的分子结构。     

CO_2和丙三醇直接合成碳酸甘油酯的新方法

报道了一种以CO_2和丙三醇为原料,Cs_2CO_3为碱,DMF为溶剂,bmimBF_4为增溶剂,直接合成碳酸甘油酯(GC)的新方法。在最优反应条件[丙三醇5 mmol,Cs_2CO_310 mmol,CH_2Cl_25 m L,bmimBF_41 m L,DMF 5 m L,P(CO_2)1 MPa,于100℃反应24 h]下,GC收率76%,其结构经1H NMR和ESI-MS确证。在最优条件下进行50倍放大实验,GC收率72%。     

Synthesis of 2-Substituted Benzimidazoles, Benzoxazoles, and Benzothiazoles from Arylsulfonyl(thio)propionitriles

The reaction of nitriles and of methyl imino ester hydrochlorides of arylsulfonyl(thio)propionic acids with o-phenylenediamine, o-aminophenol, and o-aminothiophenol has been studied. A series of new 2-substituted benzazoles has been synthesized containing arylsulfonyl(thio)propionic acid fragments.     

磷钨酸催化合成三醋酸甘油酯

以磷钨酸为催化剂,对冰醋酸与甘油的酯化反应进行了研究。考察了催化剂用量、酸醇比和带水剂对酯化反应的影响,探讨其最佳反应条件为：催化剂用量为反应物质量的3.8％,油浴温度为135℃－155℃,反应时间7h,酯收率达84.6%。     

Phosphorylation and Thiophosphorylation of 2-Substituted Benzoxazoles and Their Biological Activities

Novel organophosphorus compounds have been conveniently prepared using 2-(2′-hydroxynapthyl)benzoxazole and 2-(2′-aminophenyl)benzoxazole as starting materials. Phosphorylation and thiophosphorylation was performed using different molar ratio (1:1, 1:2 and 1:3) of phosphorus oxychloride/thiophosphoryl chloride and substituted benzoxazole. The toxicity of newly synthesized phosphorylated/thiophosphorylated compounds was tested on Aspergillus niger and Fusarium oxysporium. All were found antifungal agents. Plausible structures have been proposed on the basis of IR, ¹ H NMR, ³¹ P NMR spectral studies.     

Palladium(II) Immobilized Onto the Glucose Functionalized Magnetic Nanoparticle as a New and Efficient Catalyst for the One‐pot Synthesis of Benzoxazoles

Palladium(II) have been immobilized into the nano magnetic Fe₃O₄ which was functionalized with glucose in order to achieve a one‐pot synthesis of 2‐substituted benzoxazole derivatives with high yields in the diverse range of organic solvents. The nano catalyst is highly dispersive in polar solvents and can be easily recovered and reused for 6 runs without significant loss of its activity. Finally, the catalyst was fully characterized by FT‐IR, TGA, CHN, SEM, EDX and atomic absorption spectroscopy.     

Synthesis of certain benzylidene derivatives of lagochilin

Methods for preparing certain aromatic acetals of 3,15,16,18-tetrahydroxy-9,13-epoxylabdane are described. The structures of the resulting acetals are confirmed by IR and PMR spectra. Certain physicochemical constants of the compounds are presented.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 225–226, May–June, 2000.     

Aromatic Amines in Organic Synthesis. Part II. p-Aminocinnamaldehydes

Ten derivatives of p-aminocinnamic aldehydes were prepared from the reaction of either aromatic amines with dimethylaminoacrolein or benzaldehydes with acetaldehyde. Their chemical structure and purity were verified by ¹H NMR, ¹³C NMR and IR spectroscopic methods. We found that the synthesis applying dimethylaminoacrolein as the reagent gets better yields than the one based on the reaction with acetaldehyde. The yields of the cinnamic aldehydes varied according to the type of the amino group and the number and position of the substituents. The basic spectroscopic properties of the p-aminocinnamic aldehydes are also described since the compounds may be a precursor for the synthesis of dyes for diverse applications, e.g., in medicine and optoelectronics.