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1.
辣椒碱新同系物的合成、表征及辣构关系的初步探讨   总被引:1,自引:0,他引:1  
合成了两种辣椒碱同系物的新成员:反-N-(4-羟基-3-甲氧基苄基)-8-甲基-4-壬烯酰胺和N-(4-羟基-3-甲氧基苄基)-3,7-二甲基-6-辛烯酰胺,并用元素分析,FT-IR,1H NMR,13C NMR等方法对其结构进行了表征,还用斯科维尔感官评定的方法对其辣度进行了测定,分别为1.2×107和3.0×106SHU.并将它们的结构和辣度与辣椒碱、降辣椒碱和高辣椒碱进行了对比,总结出影响辣椒碱同系物辣度的结构因子为脂酰基双键的位置、脂酰基主链的长度及支链.  相似文献   

2.
以N-羟甲基丙烯酰胺和苯酚类化合物为原料,合成了N-(2-羟基-3-丙烯酰胺甲基-4,6-二甲基苄基)丙烯酰胺(HMABA)、N-(2-羟基-3-丙烯酰胺甲基-4,5-二甲基苄基)丙烯酰胺(AMHBA)、N-(3,5-二甲基-4-羟基苄基)丙烯酰胺(MHBA)、N-(3,6-二甲基-4-丙烯酰胺甲基-2-羟基苄基)丙烯酰胺(MAHBA)和N-(2甲氧基-4-甲基-5-丙烯酰胺甲基苄基)丙烯酰胺(MMABA)5个类辣素结构的丙烯酰胺衍生物。 通过红外光谱(IR)、核磁波谱(1H NMR)、质谱(HR-MS)和元素分析对化合物的结构进行了表征。 抑菌试验表明,HMABA对金黄色葡萄球菌和大肠杆菌的抑制效果最好,最低抑菌浓度均可达0.125 g/L。 将此5个化合物作为防污剂制备海洋防污涂料,120 d的实海结果表明,基本无污损海生物附着。  相似文献   

3.
采用高效液相色谱技术测定干辣椒及其制品中辣椒碱类物质的含量,计算出辣度,并对8个品种的干辣椒和26种干辣椒制品的辣度进行了评价。结果表明,仅根据辣椒碱和二氢辣椒碱的含量并不能正确区分干辣椒品种间的差异;根据Scoville指数将辣椒及其制品辣度分为5级,并在包装上用不同颜色区分。该分级方法可对辣椒及其制品进行有效的分级,并使消费者更直观的对辣椒产品进行选择。  相似文献   

4.
氟硅协同改性丙烯酸树脂的合成与防污性能研究   总被引:1,自引:0,他引:1  
以甲基丙烯酸十二氟庚酯(FMA)、甲基丙烯酸聚二甲基硅氧烷基酯(SMA)、甲基丙烯酸甲酯、丙烯酸正丁酯、甲基丙烯酸正丁酯和丙烯酸乙酯为共聚单体,通过溶液聚合反应合成出侧链含有机氟、有机硅的丙烯酸树脂.通过核磁共振氢谱(1H-NMR)、核磁共振氟谱(19F-NMR)、红外光谱(FTIR)对聚合物的结构进行了表征.通过扫描电镜(SEM)、接触角测试和生物评价等方法,探讨了FMA、SMA含量对树脂涂膜性能的影响.结果表明氟硅改性的丙烯酸树脂比单独含氟或含硅改性的丙烯酸树脂具有更低的表面能,而且氟硅改性的丙烯酸树脂涂膜比商业化的聚硅氧烷涂膜具有更好的防污性能.  相似文献   

5.
以辣素功能结构单体N-(4-羟基-3-甲氧基-苄基)-丙烯酰胺(HMBA)为疏水单体,与丙烯酰胺(AM)和2-丙烯酰胺基-2-甲基丙磺酸钠(NaAMPS)通过自由基胶束共聚,制得三元疏水缔合聚合物P(AM-NaAMPS-HMBA)(简称PAAH). 采用紫外-可见光谱、核磁共振氢谱、热重分析及扫描电子显微镜对共聚物的结构及形貌进行表征,利用原子力显微镜对聚合物水溶液的微观形貌进行观察,并对其溶解性、疏水缔合性、耐温性及抑菌性能进行了研究. 结果表明,所得共聚物中疏水单体含量与投料比基本一致;PAAH具有良好的速溶性,当聚合物浓度超过一定值后,溶液黏度急剧增加,且随着疏水单体含量增加,疏水缔合性能增强;原子力显微镜观察证实了聚合物水溶液中网络结构的存在. 与未改性的P(AM-NaAMPS)(简称PAA)共聚物相比,引入具有生物活性且带有刚性苯环结构的HMBA单体可使PAAH共聚物热稳定性增强,耐温性能提高,并赋予其优良的抑菌性能.  相似文献   

6.
王平  王晓晶  潘小霞  杨淬  黄超 《化学通报》2018,81(4):355-360
斑蝥素衍生物具有结构多样性和良好的抗肝癌活性。本文以呋喃、顺丁烯二酸酐为原料,合成了35个斑蝥素衍生物。以顺铂为阳性对照药,经MTT法测试了所合成化合物对人肝癌HepG2细胞的体外抗肿瘤活性。结果表明,化合物6d、6f、6g、6h、6i的抗肝癌活性与顺铂相当,其中,斑蝥素酰亚胺类化合物具有较好的抗肝癌活性,且当取代基为吸电子基或含氮杂环时化合物显现出较强的抗肝癌活性,该类化合物具有潜在的抗肝癌应用价值。  相似文献   

7.
碳点是一类环境友好且性能独特的纳米粒子, 在光电转换、 生物医学、 催化及储能等领域的研究日益活跃. 碳点主要分为碳量子点(CQDs)、 石墨烯量子点(GQDs)和碳化聚合物点(CPDs), 其中CPDs作为一种新型碳点, 具有合成原料广泛、 碳化程度及共轭结构可调且材料相容性好等优点. 本文综合评述了近年来碳点尤其是CPDs的合成方法; 阐述了通过选择前驱体分子、 控制反应条件及掺杂原子等手段实现对其碳化和共轭程度、 晶格和能级结构的调控, 从而建立碳点及其杂化与复合材料微纳结构与性能之间的关系; 最后, 介绍了碳点在生物标记与成像、 光(电)催化、 光电转换及储能等领域的应用, 并对碳点领域的发展前景进行了展望.  相似文献   

8.
合成了17个在结构上具有一定递变规律的新磺酰脲类化合物,经元素分析、 ̄1HNMR和IR确定了其结构。讨论了该类化合物的分子及晶体结构特征。测定了所合成化合物的除草活性,并讨论了活性规律。  相似文献   

9.
蔡铭  邵亮  杨帆  张继虹  俞飞 《有机化学》2022,(5):1453-1462
前期研究发现齐墩果酸(OA)的C28位葡萄糖偶联物在细胞水平具有显著抗流感病毒的活性,但不同五环三萜母核偶联葡萄糖抗流感病毒活性的影响并未阐明.本研究采用不同五环三萜母核,通过Cu(I)催化的炔烃-叠氮化物环加成反应(Cu AAC),与葡萄糖偶联制备得到化合物物4c~8d,通过体外抗流感病毒A/WSN/33(H1N1)活性研究,发现化合物4d具有显著的抗流感病毒活性(IC50为9.09μmol/L),且对MDCK(Madin-Darbey CanineKidney)细胞无明显毒性(CC50>100μmol/L).构效关系研究明确了葡萄糖模块以及五环三萜母核对化合物抗流感病毒活性的提升均具有重要作用.本研究进一步完善了五环三萜及其衍生物抗流感病毒的构效关系,为这类天然产物抗病毒的深入研究奠定了基础.  相似文献   

10.
通过文献方法合成了具有较好平面共轭结构和较高电子云密度的5-氨基-2-芳基-3H-色烯[4,3,2-de][1,6]并二氮杂萘-4-腈(4)和5-氨基-2-芳基-3H-喹啉[4,3,2-de][1,6]并二氮杂萘-4-腈(6),研究了稠合环数、荧光助色团数量以及取代基类型对产物发光性能的影响,探索了其结构与发光性能之间的关系.在发光性能构效关系指导下初步探究了化合物4对9种金属离子的识别,并从产物中筛选得到了具有进一步研究价值的、具开发为有机荧光材料潜质的产物.  相似文献   

11.
Ten capsaicin analogues were synthesized and their pungency degrees were determined through Scoville Organoleptic Test.The relationship between the structure and pungency degree of these capsaicin analogues was discussed.Then four of these capsaicin analogues with higher pungency degree were picked out and added to anti-biofouling paints as repellents to study their anti-biofouling performance by shallow sea buoyant raft hung-plate experimentation.The results showed that capsaicin and dihydrocapsaicin exhibited equally good anti-biofouling performance while nordihydrocapsaicin and N-vanillylnonanamide had poor anti-biofouling performance.Experimental results also showed that the paints with only 0.1% capsaicin or dihydrocapsaicin as repellent without any other biocides had also exhibited good anti-biofouling performance,which provided a new idea for developing novel,more environment-friendly and Cu2O-free antifouling paints.  相似文献   

12.
13.
Membrane biofouling refers to the undesirable accumulation (attachment and growth) of microorganisms on a membrane surface, and has been a major problem in the application of membrane technology in water and wastewater treatment. In this study, the surface of a base membrane made of chitosan/cellulose acetate blend was modified by reacting with heparin, quaternary ammonium or being immobilized with silver ions. The purpose of the modifications was to increase the surface hydrophilicity, alter the surface charge property or endue the surface with anti-bacteria function. The modified membranes were then examined for their anti-biofouling performance in terms of the anti-adhesion and anti-bacteria effects, with Escherichia coli pure culture and mixed culture bacteria in a bioreactor that simulated the activated sludge wastewater treatment process. The results clearly show that the hydrophilicity of a membrane, although important, is not an effective indicator for the tendency of membrane biofouling but the nature of the surface charges of the membrane also plays a very important role. It was found that the anti-adhesion approach that prevents the initial attachment of bacteria on a membrane surface is a more effective method than the anti-bacteria approach that aims at killing bacteria already attached on the membrane surface. The best performance for minimizing membrane biofouling has, however, been realized through a modified membrane surface that has effective anti-adhesion property plus additional anti-bacteria function, with the latter as a safe guard in case some bacteria do attach to the surface of a membrane.  相似文献   

14.
研究了气体中合成辣椒素(OC)的固体吸附-气相色谱检测方法,建立了气体样品经XAD-2吸附后于CH_2Cl_2溶液中解析,采用毛细管色谱柱分离,FTD检测器进行检测的技术途径.色谱柱:HP-5;载气:高纯氮气(1.2 mL/min);进样口温度:250℃;检测器温度:280℃;程序升温:初始温度180℃,保持0.5 min后以30℃/min的速率升至250℃保持5 min;对影响样品采集和检测的条件进行了选择研究,方法平均回收率为91.5%;平均相对标准偏差为3.2%(n=6);对气态OC的最低检出浓度为10 μg/m~3;在5.0~1000.0 μg/mL范围内有良好的线形关系(r=0.9996).  相似文献   

15.
无C环青蒿素类似物的合成研究   总被引:3,自引:0,他引:3  
以天然的(-)-香芹酮为原料,设计、合成了四种环状烯醇醚,它们是标题化合物的关键中间体,然而这些化合物出乎意料地与单线态氧不发生反应,仅为光氧化反应提供了有参考价值的经验积累,以(-)-薄荷醇为原料用同样方法则可合成得到化合物4的骨架化合物的混合物。  相似文献   

16.
In an attempt to develop potent antitumor agents,new rhodacyanine analogues containing the pyridinium ring(5a-5h),the isoquinolinium ring(6a-6c) and the quinolinium ring(7a-7e) linked to the rhodanine ring via N-N covalent bond were designed, synthesized and evaluated for antitumor activity against human lung cancer cell line(H460) by MTT assay in vitro.Most of the tested compounds showed enhanced antitumor activity with IC50 values ranging from 0.006 to 9.2 u,mol/L as compared to the lead compound MKT-077.Among them,the most promising compound 7d(IC50 = 0.006μmol/L) was 216.7 times more active than MKT-077(IC50 = 1.3μmol/L).The preliminary structure-activity relationship of the target compounds was discussed.  相似文献   

17.
Diastereoisomeric analogues of d4T having an isochroman core as the glycone moiety have been prepared in seven steps. Starting from phthalaldehyde, two chiral centres analogous to the α/β anomers of D/L sugars were created. The first was obtained enantiomerically pure via asymmetric dihydroxylation and the second via cyclisation of an aldehyde group with a primary hydroxyl group. Retention of chiral integrity at the C4 site enabled enantiomerically pure nucleoside analogues to be obtained.  相似文献   

18.
The synthesis and X-ray crystal structure of the first example of arylphosphinosugar are reported. The protected polyhydroxylated 1,2-oxaphosphinane is prepared by a two steps sequence (phenylphosphinate addition on protected mannofuranose followed by intramolecular transesterification) on gram scale. Deprotection of the di-isopropylidene derivative using acidic cation-exchange resin affords the free hydroxy organophosphorus heterocycle analogous to C-arylglycosides.  相似文献   

19.
Based on the crystal structures of human vitamin D receptor (hVDR) bound to 1α,25-dihydroxy-vitamin D(3) (1,25 D) and superagonist ligands, we previously designed new superagonist ligands with a tetrahydrofuran ring at the side chain that optimize the aliphatic side-chain conformation through an entropy benefit. Following a similar strategy, four novel vitamin D analogues with aromatic furan side chains (3a, 3b, 4a, 4b) have now been developed. The triene system has been constructed by an efficient stereoselective intramolecular cyclization of an enol triflate (A-ring precursor) followed by a Suzuki-Miyaura coupling of the resulting intermediate with an alkenyl boronic ester (CD-side chain, upper fragment). The furan side chains have been constructed by gold chemistry. These analogues exhibit significant pro-differentiation effects and transactivation potency. The crystal structure of 3a in a complex with the ligand-binding domain of hVDR revealed that the side-chain furanic ring adopts two conformations.  相似文献   

20.
The synthesis of two new bicyclic nucleoside analogues is reported. These compounds are iso-homonucleoside and are synthesised through a 1,3-dipolar cycloaddition of an enantiopure cyclic nitrone to protected allyl acohol and subsequent introduction of thymine by a Mitsunobu reaction.  相似文献   

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