1,354 research outputs found

    根霉3078的代谢产物的研究

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    从根霉 30 78菌丝体的甲醇提取物中分离得到 9个化合物 ,通过波谱分析 ,鉴定为 5α,8α 表二氧 (2 0S ,2 2E ,2 4R) 麦角甾 6 ,2 2 二烯 3β 醇 (1)、甘油醇 1 单油酸酯 (2 )、4 羟基苯乙酮 (3)、4 羟基苯乙酸 (4 )、(2 0S ,2 2E ,2 4R) 麦角甾 7,2 2 二烯 3β ,5α ,6 β 三醇 (5 )、(S) 3 羟基 3 苯基丙酸 (6 )、胸腺嘧啶 (7)、尿嘧啶(8)和腺苷 (9

    Study on synthesis of 7-hydroxy-4-methylcoumarin

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    本文主要针对磷钨酸(HPW)催化合成7-羟基-4-甲基香豆素效率低、成本高等问题,选取聚乙烯基吡咯烷酮(PVP,K30)和N-甲基吡咯烷酮(NMP)为载体,通过浸渍法制备负载磷钨酸催化剂,改善其催化性能,建立7-羟基-4-甲基香豆素高产率的新工艺。主要开展了以下几方面研究: 1.聚乙烯基吡咯烷酮负载磷钨酸催化剂(PVP-HPW)和N-甲基吡咯烷酮负载磷钨酸催化剂([NMP]3PW)的制备及表征:采用浸渍法制备PVP-HPW和[NMP]3PW催化剂,运用红外光谱、热重分析、元素分析、紫外-可见漫反射-近红外光谱分析等多种表征方法对合成的催化剂进行表征。结果表明,PVP-HPW和[NMP]3PW...In order to solve the problems of the low catalytic efficiency and high cost in synthesis of 7-hydroxy-4-methylcoumarin which is catalyzed by phosphotungstic acid, We selected PVP (K30) and NMP as supporter to improve the catalytic performance by the method of impregnation to prepare supported phosphotungstic acid catalysts and build new 7-hydroxy-4-methylcoumarin’s synthetic processes with high y...学位:工程硕士院系专业:化学化工学院_工程硕士(化学工程)学号:2062013115149

    AHPN衍生物的合成及其与RARγ的结合活性研究

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    目的本实验以6-{3’-(1-金刚烷基)-4’-羟基苯基}-2-萘甲酸(AHPN)母核为结构基础,设计、合成一系列AHPN衍生物,并对这些衍生物做初步的活性筛选,期望找到活性显著的衍生物。方法以对溴苯酚和1-金刚烷醇为原料经取代、缩合、氧化、还原等反应合成AHPN衍生物,经过1H-NMR、13C-NMR、HR-MS表征,并利用Biacore技术检测衍生物与蛋白质之间的结合能力。结果衍生物7c、6c、6e、6h显示出了显著优于先导化合物AHPN与视黄酸核受体γ(RARγ)的结合能力,亚磷酸二甲酯基与氮杂环的引入提高了该类化合物的活性。结论该类AHPN衍生物与RARγ结合能力显著,有进一步研究的价值。扬州市邗江区科技计划项目资助;;福建省基金项目资助(2014Y0044);;国家海洋局第三海洋研究所基本科研业务费专项资金资助项目(海三科2016044

    1,3-取代吲唑类低氧诱导因子l抑制剂的设计合成及其抗肝癌活性

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    低氧诱导因子l(HIF-1)与肿瘤细胞的生长、侵袭和耐药密切相关,在肿瘤细胞内HIF-1高度表达,因此新型的HIF-1抑制剂可作为潜在的抗肿瘤药物。本文合成了9个1,3-取代吲唑衍生物。通过蛋白质印迹(Western Blot)法及实时定量荧光PCR(Real time-PCR)等方法检测了其对HIF-1及其靶基因血管内皮生长因子(VEGF)表达水平的影响,并以3-(5’-羟甲基-2’-呋喃基)-1-苯甲基吲唑(YC-1)为阳性对照药物初步评价了其体外抗肝癌细胞增殖的生物活性。实验发现化合物7b可显著抑制HIF-1及其下游靶基因VEGF的表达,且体外抗肝癌增殖生物活性优于YC-1,半抑制浓度(IC50)值为10.37μmol/L。研究结果表明,3-(5’-羟甲基-2’-呋喃)-1-(1″-对甲苯磺酰基)吲唑具有靶向抑制HIF及良好的抗肝癌活性作用。福建省科技厅项目(2015Y0081,2015J01350);;厦门大学大学生创新创业训练计划项目(2016X0644,20720152005)~

    Insecticidal Activity for Benzaldehyde L-Cysteine Schiff Base Combined with Xylosma Wood Vinegar

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    木醋碱杀虫剂是一种基于木炭副产物木醋液的绿色杀虫剂,是将精馏木醋液、苯甲醛L-半胱氨酸席夫碱、水杨酸按照一定比例配制而成的.以酪氨酸酶筛选模型研究了苯甲醛L-半胱氨酸席夫碱、精馏木醋液、木醋碱杀虫剂对酪氨酸酶的抑制作用,其导致酪氨酸酶活性的半抑制质量浓度(IC50)分别为15,2.53,0.53 mg/m L.探讨了木醋碱杀虫剂对小菜蛾(Plutella xylostella)、棉铃虫(Helicoverpa armigera)、玉米螟(Pyrausta nubilalis)幼虫的杀虫活性,结果表明木醋碱杀虫剂中苯甲醛L-半胱氨酸席夫碱质量浓度达到15 mg/m L时即可对小菜蛾、棉铃虫、玉米螟二龄幼虫达到很好的杀灭效果.急性毒理实验表明木醋碱杀虫剂实际无毒.慢性毒理研究按照3 g/kg给药量连续灌胃3个月,昆明小鼠的肝脏和肾脏并不存在毒理性变化,表明木醋碱杀虫剂没有慢性毒性.综上所述,木醋碱杀虫剂不仅对酪氨酸酶有很好的抑制作用,还对小菜蛾、棉铃虫、玉米螟等常见农业害虫具有较强的毒杀活性,且实际无毒,具有良好的农业应用前景.The wood vinegar was based on by-product in the process of firing Xylosma charcoal.The wood vinegar base insecticide was a new green type insecticide.We mixed the rectificated wood vinegar,benzaldehyde L-cysteine Schiff base and salicylic acid to make the wood vinegar base insecticide proportionally.The inhibition on tyrosinase in screening model of benzaldehyde L-cysteine Schiff base,rectificated wood vinegar and the wood vinegar base insecticide were determined. The half maximal inhibitory concentration( IC50) were 15,2. 53,0. 53 mg/m L,respectively.Additionally,the insecticidal effects on Plutella xylostella,Pyrausta nubilalis and Helicoverpa armigera of wood vinegar base insecticide were investigated.The results showed that the wood vinegar base insecticide could effectively kill the second-stage juveniles of P.xylostella,P. nubilalis and H. armigera. The results showed that the wood vinegar base insecticide had insecticidal effect.The acute toxicological results showed that the wood vinegar base insecticide had no toxicity.In the chronic toxicological experiment,the group was given a gavage of 3 g / kg with the wood vinegar base insecticide in 3 months.We took the liver and kidney in paraffin section and HE staining after executing the Kunming mouse with cervical dislocation method.The results showed that the wood vinegar base insecticide had no chronic toxicity.In conclusion,the wood vinegar base insecticide could not only inhibit the tyrosinase acitivity,but also show good insecticidal effects on P. xylostella,P. nubilalis and H. armigera with low toxicity.The wood vinegar base insecticide had shown good application prospects in agricultural areas.国家自然科学基金(31371857

    Studies on Nano Cerium Oxides Catalyzed-oxidation of Lignin into Aromatic Compounds

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    基于木质纤维素的生物炼制,不仅能可持续地提供能源和化学品,也可以有效减少温室气体的净排放,为巨量的农业废弃物的高附加值转化提供最佳解决方案。然而,由于木质素是一种结构复杂、性质稳定、难溶、难解聚的芳香高分子,且与纤维素通过物理-化学作用紧密伴生,分离成本昂贵,转化利用困难,成为生物炼制的瓶颈之一。通过对木质素氧化解聚策略和机理的研究,使木质素定向氧化解聚为高附加值的芳香醛/酮/酸等化合物,是提高生物炼制经济性的根本途径。以二氧化铈为代表的部分稀土纳米氧化物在木质素的定向催化氧化反应中表现出优异性能,然而目前对它们的构效关系和催化机理的认识不足。基于此,本报告通过研究催化剂的设计,首先以纳米Ce...Biorefinery of lignocellulose not only provides the sustainable energy and chemicals, but also reduces the net emissions of greenhouse gases, and provides the best solution for high-value utilization of a huge amount of agricultural waste. However, lignin is a stable and recalcitrant aromatic polymer with complex structure, and closely associated with cellulose through physical-chemical interactio...学位:博士后院系专业:化学化工学院_化学工程学号:201317004

    Characterization and cloning and expression of Polyphenol Oxidase (PPO) from Canarium album

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    多酚氧化酶(EC.1.14.18.1)广泛存在于动物、植物和微生物体内,是一种由核基因编码的含铜金属酶。它是果蔬储藏和加工过程中酶促褐变的重要酶类,能够催化酚类物质的氧化。以橄榄(长营)为原料提取多酚氧化酶进行了分离纯化,得到比活力为1834U/mg的多酚氧化酶粗酶液。研究橄榄多酚氧化酶的理化性质,酶的pH和最适温度分别为6.0和30℃,酶在低于60℃和在pH4.0~8.0范围内较稳定;在30℃、pH6.0条件下,多酚氧化酶催化L-DOPA氧化反应的Km为3.884mmol/L。测定了几种修饰剂对橄榄多酚氧化酶的修饰作用,结果表明二硫键、精氨酸残基、赖氨酸残基和丝氨酸残基对多酚氧化酶具有修饰作...Polyphenol oxidase is widely distributed in animals, plants and microorganisms. It’s a copper-containing enzyme which has complex constructures. Polyphenol oxidase play an important role during the process of enzymetic browning in vegetable and fruit, for the reason that it can catalyze the melanin synthesis. In this paper, we purified the PPO from Canarium album and studied so...学位:理学硕士院系专业:生命科学学院_细胞生物学学号:2162013115254

    Total Synthesis of Hapalosin and Its Analogues:Construction of Three Small Hapalosin C-9 Analogues Libraries and Studies on Total Synthesis of Melleumins A and B

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    环肽类化合物是一类结构复杂多样的天然产物。自然界中存在大量的环肽类化合物,表现出多种生物活性,如杀虫、抗菌、抗肿瘤、抗病毒、和免疫抑制等。环肽类化合物作为富有实用前景的先导化合物在药物发现中受到越来越多的关注,新的活性天然产物也不断被发现。同时,环肽类天然产物的全合成也成为不对称合成的新热点。Hapalosin(1a)是1994年从蓝藻中分离提取的一类新型结构的环肽化合物,因其对肿瘤细胞的多药耐药性细胞系有很强的抑制作用,一经发现就引起了广大合成化学家和药物化学家的关注。本论文的目标在于拓展手性合成砌块(R/S)苹果酰亚胺的多用性,将其应用于环肽类天然产物hapalosin和melleumin...Cylcopeptides with complex and diversified structures are widespread in nature. Many of them exhibit various biological activities, such as, antibiotics, antitumor, antivirus, immunosuppressive effect and pesticides. As promising lead compounds in drug discovery, cylcopeptides are receiving more and more attention. And the studies on the asymmetric total synthesis of these compounds have been a ne...学位:理学博士院系专业:化学化工学院_有机化学学号:B20022501

    丙氨酰-谷氨酰胺二肽合成工艺研究进展

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    目的:为丙氨酰-谷氨酰胺二肽(Ala-Gln)类药物的进一步研究和生产提供参考。方法:以\"丙氨酰-谷氨酰胺二肽\"\"合成工艺\"\"谷氨酸水解法\"\"D-氯(溴)代丙酸法\"\"N-羧基内酸酐法\"\"活化酯法\"\"三苯基膦/六氯乙烷缩合法\"\"Ala-Gln peptides drugs\"\"Synthetic process\"\"Appel condensation method\"等为关键词,组合查询在中国知网、Web of Science等数据库中收录的1987年1月-2017年12月发表的相关研究文献,进行归纳和总结。结果与结论:共检索到相关研究文献678篇,其中有效文献25篇。Ala-Gln以往的合成方法主要有谷氨酸水解法、D-氯(溴)代丙酸法、N-羧基内酸酐法、活化酯法、酶催化合成法等,这些方法存在步骤烦琐、反应成本高、带有毒性、合成路线长、大批量生产的产率难以控制等缺点,严重制约了其推广应用。三苯基膦/六氯乙烷缩合法具有合成成本低、可行性好、稳定性高、合成周期短等突出优点,为推动Ala-Gln类药物大规模的生产和应用提供了可能。国家自然科学基金资助项目(No.21778042);;福建省自然科学基金资助项目(No.2016J05200
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