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1.
黄烷酮是含有二氢色原酮骨架结构的黄酮类化合物。本文梳理了合成黄烷酮的文献,总结了其合成方法,按原料结构特征分类论述其合成方法:即从黄烷酮衍生物经官能团变换合成黄烷酮;查耳酮经氧-Michael加成合成黄烷酮;非查耳酮结构构建合成黄烷酮。重点论述了第二类合成方法。参考文献82篇。  相似文献   

2.
查尔酮的化学名为1,3-二苯基丙烯酮,以它为母体的天然化合物存在于红花、甘草等多种天然植物中,是植物体内合成黄烷酮的重要中间体,其自身也具有抗过敏、抗溃疡、抗肿瘤等药理作用[1-3].  相似文献   

3.
黄烷酮及其衍生物是一种重要的生物活性的天然产物,在很多复杂的天然产物中存在该骨架结构,具有广泛的生物活性,对于黄烷酮的研究越来越得到重视.手性黄烷酮其本身在植物当中是种重要的化学物质,具有潜在的药用价值,但其含量较少,很多化学家致力于通过合成的方法来解决问题,推动了对映体富集的黄烷酮类的制备,但其制备过程存在一定的局限性,对于一些复杂结构的黄烷酮类化合物仍很难实现,这将是未来需要攻克的难题.本文综述了近年来黄烷酮的不对称合成方法.合成方法包括对羰基的还原、手性拆分、碳-碳键的形成、碳-杂键的形成及其他类型的合成方法.  相似文献   

4.
B环取代的新型磺烷酮衍生物的合成及杀菌活性   总被引:1,自引:0,他引:1  
丁宇  杨光富 《应用化学》2001,18(10):785-789
设计合成了11种B环上含不同性质取代基的新型黄烷酮衍生物,采用核磁共振氢谱及元素分析对所合成的化合物进行了结构表征。初步杀菌活性测试结果表明,所合成的化合物均表现出不同程度的杀菌活性,其中化合物3b(3'-硝基黄烷酮)在质量浓度为50、10和1μg/L下对水稻纹枯病、棉花枯萎病、苹果轮纹病、小麦赤霉病以及芦笋褐斑病均表现出100%的抑制活性。初步构效关系研究表明,B环取代基的电性性质及疏水性质对化合物的杀菌活性有重要影响。  相似文献   

5.
马涛  杨金会  牛明杰  叶子平  李方辉 《应用化学》2017,34(10):1140-1149
3种香叶基黄烷酮是从毛泡桐(Paulownia tomentosa)水果中分离出的3种具有相似结构的黄酮类化合物。我们以廉价的2,4,6-三羟基苯乙酮,羟基苯甲醛为原料经过取代、氯甲基甲基醚保护、羟醛缩合、分子内的麦克加成反应以及脱甲基甲基醚合成了3个香叶基取代黄烷酮。其结构经过核磁共振氢谱及碳谱(1H NMR,13C NMR)和高分辨质谱(HRMS)等技术手段进行了表征,并采用四氮唑蓝(MTT)法测试了合成化合物对肺癌细胞A459的体外抗肿瘤活性。结果表明,所合成的化合物均具有一定的抗肺癌细胞活性,其中化合物2抗肺癌活性明显优于化合物1和3,其半数抑制浓度为25.6μmol/L,为临床疾病的治疗和药物的研发提供了参考。  相似文献   

6.
苯甲叉基丙二腈与间苯三酚反应产物结构的辩证   总被引:1,自引:0,他引:1  
苯甲叉基丙二腈与间苯三酚反应产物结构的辩证鲁宽科,谭镇,李裕林(兰州大学化学系,兰州,730000)关键词香豆素,黄烷酮,结构文献[1,2]报道了柚皮素(Naringenin)、乔松素(Pinocembrin)等12种黄烷酮的合成路线,认为其反应过程...  相似文献   

7.
张剑锋  江峰周雄 《合成化学》2007,15(3):319-321,349
在DMSO/I2的氧化作用下,由2′,4′-二氢-6′-甲氧基-3′,5′-二甲基查耳酮可合成一种全新结构的黄酮:7-羟基-5-甲氧基-6,8-二甲基黄酮(产率91%),而在HCl/MeOH作用下则得到了两种黄烷酮:7-羟基-5-甲氧基-6,8-二甲基黄烷酮(产率70%)和5,7-二羟基-6,8-二甲基黄烷酮(产率20%)。  相似文献   

8.
张虹锐  吴隆民 《有机化学》2005,25(10):1248-1253
羟基取代的黄烷酮与NO反应, 得到了羟基邻位或对位单硝基化产物. 随着反应时间的延长, 有羟基邻位和对位双硝基化以及羟基两个邻位双硝基化产物生成. 多羟基取代的黄烷酮可以生成多硝基化产物.  相似文献   

9.
以3-甲氧基甲氧基苯甲醛和2,4,6-三甲氧基-3-异戊烯基苯乙酮为原料,经烷基化和缩合反应合成了新化合物——2’-羟基-4-甲氧基-3,4’,6’-三甲氧甲氧基-3’-异戊烯基査尓酮(6);6经环合反应合成了新化合物——(±)-5,7,3’-三甲氧甲氧基-4’-甲氧基-8-异戊烯基黄烷酮(7);7经脱保护和环合反应实现了天然产物(±)-5,7,3’-三羟基-4’-甲氧基-8-异戊烯基-黄烷酮(1,总收率11.6%)和(±)-5,3’-二羟基-7,8-(2,2-二甲基吡喃)-4’-甲氧基黄烷酮(2,总收率10.5%)的全合成,其中1为新化合物,其结构经1H NMR,IR和MS表征。  相似文献   

10.
以2′-羟基查耳酮为原料,吡啶-水溶液为催化剂,分别在加热和光照条件下合成黄烷酮,考察了吡啶-水体积比、加热温度、光照强度、反应时间等因素的影响。结果表明,当吡啶-水体积比为4∶6,加热温度为90℃,反应时间为1 h时,黄烷酮产率达89.0%;在吡啶-水体积比为4∶6下,采用500W氙灯辐射7.5 h,黄烷酮产率达93.7%。  相似文献   

11.
Flavanones have been synthesised by cyclisation of 2′-hydroxychalones with potassium ferricyanide using phase transfer catalysis.  相似文献   

12.
Summary Flavanones ofArachis hypogaea, Hemizonia increscens, Eriodictyon glutinosum andThymus vulgaris extracts have been stereospecifically analysed by gradient elution on a column of cellulose triacetate supported on silica gel diol. The stereochemistry of naringenin, eriodictyol and homoeriodictyol was in favour of the 2S-configurated flavanones.  相似文献   

13.
Flavanones, chromanones, and related structures are privileged natural products that display a wide variety of biological activities. Although flavanoids are abundant in nature, there are a limited number of available general and efficient synthetic methods for accessing molecules of this class in a stereoselective manner. Their structurally simple architectures belie the difficulties involved in installation and maintenance of the stereogenic configuration at the C2 position, which can be sensitive and can undergo epimerization under mildly acidic, basic, and thermal reaction conditions. This review presents the methods currently used to access these related structures. The synthetic methods include manipulation of the flavone/flavanone core, carbon-carbon bond formation, and carbon-heteroatom bond formation.  相似文献   

14.
The non-Faradaic preconcentration behaviour of nine flavonoids (six flavones: fisetin, galangin, morin, quercetin, rhamnetin, rutin, and three flavanones: hesperidin, hesperitin, naringin) at a carbon-paste (nujol/graphite) electrode and the factors affecting it (pH, accumulation potential, presence of various surfactants) for their subsequent differential pulse voltammetric determination are examined. All flavones tested are readily accumulated on the carbon paste electrode resulting in a considerable signal enhancement making determinations feasible down to 10−8 − 10−7 M after preconcentration for 1–4 min. Flavanones are not preconcentrated so their lower determination limits are of the order of 10-6 M. A simple voltammetric procedure for the determination of rutin in a multivitamin preparation is presented.  相似文献   

15.
Understanding the factors influencing flavonone extraction is critical for the knowledge in sample preparation. The present study was focused on the extraction parameters such as solvent, heat, centrifugal speed, centrifuge temperature, sample to solvent ratio, extraction cycles, sonication time, microwave time and their interactions on sample preparation. Flavanones were analyzed in a high performance liquid chromatography (HPLC) and later identified by liquid chromatography and mass spectrometry (LC-MS). The five flavanones were eluted by a binary mobile phase with 0.03% phosphoric acid and acetonitrile in 20 min and detected at 280 nm, and later identified by mass spectral analysis. Dimethylsulfoxide (DMSO) and dimethyl formamide (DMF) had optimum extraction levels of narirutin, naringin, neohesperidin, didymin and poncirin compared to methanol (MeOH), ethanol (EtOH) and acetonitrile (ACN). Centrifuge temperature had a significant effect on flavanone distribution in the extracts. The DMSO and DMF extracts had homogeneous distribution of flavanones compared to MeOH, EtOH and ACN after centrifugation. Furthermore, ACN showed clear phase separation due to differential densities in the extracts after centrifugation. The number of extraction cycles significantly increased the flavanone levels during extraction. Modulating the sample to solvent ratio increased naringin quantity in the extracts. Current research provides critical information on the role of centrifuge temperature, extraction solvent and their interactions on flavanone distribution in extracts.  相似文献   

16.
用原子吸收光谱法测定延边地区317名65~108岁老人头发中锌、铜、铁、锰、镁含量,观察不同民族、性别、年龄老人这些元素的差异。结果表明:1.朝鲜旗发锌低于汉族,满族发铜低于汉族、朝鲜族,汉族发镁高于朝鲜族、满族,发铁、发锰在汉、朝、满民族之间无区别。2.汉族、朝鲜族男发锌高于女性,汉族女性发铜高于男性,发铁、发锰、发镁在性别之间无区别。3、90岁组朝鲜族发锰、发镁低于65岁、76岁组,朝鲜族发锌、发铜、发铁在65~108岁之间无统计学意义。  相似文献   

17.
The accelerated growth of aquaculture has resulted in a series of harmful effects to human health. The widespread and unrestricted use of antibiotics in this industry, to prevent bacterial infections, leads to remaining amounts in the aquatic environment. This has resulted in the emergence of antibiotic-resistant bacteria in aquaculture environments, in the increase in antibiotic resistance in fish pathogens as well as in the transfer of these resistance determinants to human pathogens. Moreover, the use of large amounts of antibiotics may lead to the presence of residual antibiotics in fish tissue and fish products. Fluoroquinolones, tetracyclines, penicillins, sulphonamides and other antibiotics, exhibiting activity against both Gram-positive and Gram-negative bacteria, are widely used for the treatment and prevention of diseases in fish. An extended and comprehensive review on the recent analytical methodologies concerning antibiotic residues in fish reported in the literature is provided in the present article. Emphasis is given on sample preparation regarding isolation and purification, chromatographic conditions and method validation according to legislation. Results of published assays are comparatively presented and criticised.  相似文献   

18.
Penicillins are the most frequently found antibiotic residues in milk, as they are commonly used for the treatment of bacterial infections in cows. In the present study, we introduce a method for the rapid detection of penicillin residues in raw milk based on the determination of glucose concentration in milk with a dual flow-through biosensor. The molar concentration of glucose in milk is typically over 500 times lower than the concentration of lactose and is highly dependent on the rate of lactose hydrolysis, which is catalyzed by β-galactosidase. Glucose concentrations in milk change with variation in the β-galactosidase activity. β-Galactosidase is an enzyme produced in the microbiota in milk and its activity is inhibited by benzylpenicillin. Spiking milk with benzylpenicillin lowers glucose concentrations in comparison to high-quality milk after short storage intervals. The presence of penicillin in the milk of treated animals resulted in decreased glucose concentrations in comparison with high-quality milk that contained no antibiotics. The glucose concentration in milk samples was followed by the system enabling the elimination of the effects of bacterial respiration in the output with reliable results in less than 1?min.  相似文献   

19.
Here we report on the role of oxygen in the evolution of radial heterogeneity in the fibre structure and properties of PAN fibres stabilized in air and vacuum at different temperatures. Modulus mapping by Nano-indentation showed heterogeneous modulus distribution in the fibres treated in air, while no variation in modulus was observed in fibres processed in vacuum. Raman spectroscopy and elemental analysis revealed that the temperature dependent oxygen diffusion from skin to core of the fibres assisted in the evolution of higher extent of sp2-hybridized carbons in the skin compared to core of the air treated samples. Conversely, no radial structure variations were observed in the vacuum treated fibres. Higher modulus in the skin of air-treated fibres was due to the formation of compact structures which was associated with the enhanced intermolecular interactions facilitated by the formation of C=C bonds within the polymer backbone, promoted by oxidative-dehydrogenation reaction. Supporting these observations, the fracture morphology examined by SEM showed a brittle fracture in the skin and ductile fracture in the core.  相似文献   

20.
The PdCl2/Fe/I2/Py catalytic system (Py-pyridine), reported to be highly active in the reaction of nitrobenzene carbonylation to ethyl phenylcarbamate was studied. The present paper describes the role of catalyst components and its effect on the activity and selectivity of the catalyst. The increase in the amount of PdCl2 in the system while retaining a constant level of the other catalyst components, results in the increase of both carbamate and aniline yields. The increase in the amount of iron while retaining the other components constant, initially causes an increase in the carbamate yield; however, at Fe: Pd ratios higher than 36, the carbamate yield remains constant. The change in the amount of iron has no effect on the amount of aniline formed in the system. An increase in the amount of iodine in the system while retaining the other components constant, results in a decrease in carbamate yield and a considerable increase in the aniline yield of the reaction products.  相似文献   

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