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1.
裴文  陈霁 《化学通报》1989,(12):25-25
氟代哒嗪类化合物与有一定生理活性的氟代嘧啶类化合物有着同分异构的关系。而4-氟-3,6-二氯哒嗪又是合成其它药物的重要中间体。1984年田官荣报道了4-氟-3,6-二氯哒嗪的合成及同亲核试剂的反应性能和同类化合物  相似文献   

2.
氟代马来酐和苯肼缩合,反应先在乙醚后在25%盐酸中进行。4-氟-3-羟基-1-苯基-6-哒嗪酮(Ⅰ)的收率达54%,文献仅26%。Ⅰ和吗啡啉反应,得熔点为243~244℃的白色晶体。熔点及元素分析结果(表1)表明,产物为4-吗啡啉基-3-羟基-1-苯基-6-哒嗪酮(Ⅱ),据此作者认为氟原子位于第4位。  相似文献   

3.
在离子液体和氟化钾反应体系中,研究了卤代哒嗪化合物的氟代反应,讨论了微波辐射条件下由卤代哒嗪化合物合成氟代哒嗪化合物的方法。用离子液体作为反应介质替代了传统的分子溶剂,提高了产物收率,简化了操作。用微波反应不仅获得了较好的收率,也缩短了反应时间。利用离子液体和微波辐射条件进行氟代反应是一种绿色化学方法。  相似文献   

4.
前文[1,2]报道了氟代哒嗪二酮化合物的合成及生理活性,其合成路线较长,收率较低。  相似文献   

5.
研究了芳氧基哒嗪氧基乳酸酯合成条件,发现可通过两种途径来合成。研究了 起始物中卤素原子对其亲核取代反应的影响。通过分子力学和量化计算,发现3, 6-二氟哒嗪在亲核取代反应中较其它3,6-二卤代哒嗪有优势,实验结果证实了 3,6-二氟哒嗪在温和的条件下合成了芳氧基哒嗪氧基乳酸酯。  相似文献   

6.
哒嗪酮苷类化合物的合成研究   总被引:1,自引:0,他引:1  
赵云清  林成极  裴文 《有机化学》1990,10(2):168-170
一些嘧啶系列的苷具有较强的生理活性,其中5-氟脲苷是有效的抗癌药物。而哒嗪与嘧啶具有同分异构关系,那么,哒嗪苷类化合物是否也有相似的生理活性呢?六十年代初,Wagner等开展了这一领域的研究;到七十年代中期,Katz等合成了与天然  相似文献   

7.
众所周知,许多嘧啶的核苷类化合物都有较强的生理活性,其中5-氟脲苷是有效的抗癌药。而哒嗪和嘧啶在结构上具有同分异构关系,因此,对于哒嗪核苷类化合物的合成及其生  相似文献   

8.
以取代苯和丁二酸酐为起始原料, 经Friedel-Crafts反应, 肼合环, Br2/HOAc氧化脱氢后得到一系列1,6-二氢-3-芳基-6-哒嗪酮(2a2d). 然后将2a2d与PCl5在POCl3中回流, 得到相应的氯代产物3a3d, 将其与酰肼作用, 合环后得到一系列未见报道的哒嗪并[3,2-c]1,2,4-三唑类化合物. 所有化合物结构均经元素分析, IR, 1H NMR 和MS谱得以证实, 并对其波谱性质进行了讨论.  相似文献   

9.
氟氯代β-二酮的合成   总被引:1,自引:0,他引:1  
从二氟氯乙酸乙酯与甲基酮的Claisen酯缩合反应合成了一些氟氯代β-二酮.用格氏试剂与氟代羧酸酯加成,多氟芳基镉与乙酰氯反应以及氟代β-酮酸酯水解等方法合成了一些新的多氟烃基甲基酮R_FCOCH_3.  相似文献   

10.
采用量子化学MNDO法,计算了氟代甲酰胺和N—氟代甲酰胺的1,2—氢迁移异构化反应势能面上的反应路径。结果表明:氟代甲酰胺分子比N—氟代甲酰胺分子稳定.前者异构化为吸热反应,后者为放热反应。N—氟代甲酰胺的氢迁移势垒低于甲酰胺的氢迁移势垒.氟原子的存在使过渡态结构相对松散,有利于异构化的发生.  相似文献   

11.
以3,5-二羟基 苯甲酸为起始原料,经甲醇酯化保护羧基,与苯甲酰氯反应,得到3,5-二苯甲酰氧基苯甲酸甲酯用AlCl3.NaI去掉保护基甲基,以高收率得到3,5-二苯甲酰氧基苯甲酸。其结构均是由IR,^1HNMR,EA等方法证实。  相似文献   

12.
对20例再生障碍性贫血患者(以下简称再障)头发中12种微量元素的含量进行测定,与正常人做对照,结果发现,阴虚型患者锂、钙、锶、铬显著减少,阴虚型患者锌、镁、钡、钙、锂明显下降,阴阳俱虚型患者则12种元素均减少,并对本院治疗再障贫血的24味中药的微量元素的含量也进行测定。结合微量元素变化对指导再障的辩证组方和辩证施治提供新的思路,同时系统观察再障贫血10例治疗前后微量元素的变化情况,从微量元素角度探求再障的发症因素,认为与部分微量元素缺乏有关,补充相关的微量元素,再障患者可恢复健康。  相似文献   

13.
通过交联聚丙烯酸甲酯与乙醇胺反应,形成聚(N-羟乙基丙烯酰胺)树脂,在酸催化作用下与环氧氯丙烷反应,形成含有α-羟基氯乙基的树脂.含α-羟基氯乙基的树脂与D-丙氨酸、L-丙氨酸或甘氨酸反应,分别得到含有这3种氨基酸的吸附剂.这3种吸附剂吸附N-去甲万古霉素的结果表明,含D-丙氨酸的吸附剂的吸附量最大,含甘氨酸的吸附剂的吸附量次之,而含L-丙氨酸的吸附剂不吸附N-去万古霉素.说明前两种吸附剂对N-去甲万古霉素存在亲和吸附作用.含D-丙氨酸吸附剂的最佳吸附pH值为5.8,当吸附液中的盐(NaCl)浓度增加时,吸附量降低.用0.4mol/LNa2CO3/CH3CN(摩尔比7∶3,pH=9.5)作为洗脱剂可完全脱附被吸附的N-去甲万古霉素.  相似文献   

14.
建立了测定大豆、糙米、黄瓜、甜菜等6种植物源性农产品中(噁)霉灵残留的气相色谱-火焰光度法(GC-FPD)、气相色谱-氮磷检测法(GC-NPD)和液相色谱-串联质谱法(LC-MS/MS).GC-FPD法采用丙酮-正己烷提取样品,O,O-二甲基硫代磷酰氯衍生,GC-FPD分析,外标法定量;GC-NPD法采用丙酮-正己烷提取样品,十八烷基键合硅胶(C18)净化,GC-NPD分析,外标法定量;LC-MS/MS法,样品采用乙腈提取,石墨化碳黑(GCB)净化,LC-MS/MS分析,基质匹配外标法定量.结果表明,(噁)霉灵的响应值与其浓度间呈良好的线性关系,3种方法的相关系数均大于0.998.在3个加标浓度下,GC-FPD法中(噁)霉灵的日间平均回收率为82%~96%,日间相对标准偏差(RSD)为3.4%~12.1%,方法的定量下限为0.25 mg/kg (甜菜为0.05 mg/kg);GC-NPD法的日间平均回收率为81%~103%,日间RSD为4.1%~14.3%,定量下限为0.25 mg/kg (甜菜为0.05 mg/kg);LC-MS/MS法的日间平均回收率为74%~110%,日间RSD为2.5%~10.7%,定量下限为0.05 mg/kg.3种方法均具有良好的准确性和稳定性,可满足(噁)霉灵残留分析的要求.  相似文献   

15.
Two phosphorus‐containing acrylate monomers were synthesized from the reaction of ethyl α‐chloromethyl acrylate and t‐butyl α‐bromomethyl acrylate with triethyl phosphite. The selective hydrolysis of the ethyl ester monomer with trimethylsilyl bromide (TMSBr) gave a phosphonic acid monomer. The attempted bulk polymerizations of the monomers at 57–60 °C with 2,2′‐azobisisobutyronitrile (AIBN) were unsuccessful; however, the monomers were copolymerized with methyl methacrylate (MMA) in bulk at 60 °C with AIBN. The resulting copolymers produced chars on burning, showing potential as flame‐retardant materials. Additionally, α‐(chloromethyl)acryloyl chloride (CMAC) was reacted with diethyl (hydroxymethyl)phosphonate to obtain a new monomer with identical ester and ether moieties. This monomer was hydrolyzed with TMSBr, homopolymerized, and copolymerized with MMA. The thermal stabilities of the copolymers increased with increasing amounts of the phosphonate monomer in the copolymers. A new route to highly reactive phosphorus‐containing acrylate monomers was developed. A new derivative of CMAC with mixed ester and ether groups was synthesized by substitution, first with diethyl (hydroxymethyl)phosphonate and then with sodium acetate. This monomer showed the highest reactivity and gave a crosslinked polymer. The incorporation of an ester group increased the rate of polymerization. The relative reactivities of the synthesized monomers in photopolymerizations were determined and compared with those of the other phosphorous‐containing acrylate monomers. Changing the monomer structure allowed control of the polymerization reactivity so that new phosphorus‐containing polymers with desirable properties could be obtained. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2207–2217, 2003  相似文献   

16.
Summary The resolution of gaseous chemical species in gasliquid-solid chromatography is influenced by absorption (partitioning) in the liquid and adsorption at the liquid-solid interface. We consider fundamental mass transfer models with adsorption and partitioning effects for solid chromatographic supports covered with thin films of stationary liquid. The dynamic models, based on mass-balance partial-differential equations, include the significant phenomena: convection, axial dispersion, gas-liquid mass transfer, intraparticle diffusion, and liquid-solid adsorption. Expressions for retention time and band variance (first and second temporal moments) are presented and evaluated for four distinct models: (1) capillary tube with inner surface covered with a uniform-thickness liquid film, (2) column of nonporous spheres covered with a uniform-thickness liquid film, (3) porous spherical particles with intraparticle pores covered with a uniform-thickness liquid film, (4) porous spherical particles with intraparticle pores completely filled with liquid.  相似文献   

17.
采用闰溶出法测定82例肝炎患儿的头发中锌,铜,铅,镉含量。结果显示,大多数急,慢性肝炎患儿发锌含量降低;发铜增高者仅占1/4和1/8,肝慢性肝炎中发铜降低者红占1/3,为急性肝炎的3倍;  相似文献   

18.
稀土奥贝蠕铁制取工艺及其性能的研究   总被引:1,自引:0,他引:1  
稀土奥贝蠕铁可用含稀土的蠕化剂及等温淬火工艺稳定地制取,藉助高温扫描电子显微镜,观察并研究了稀土蠕铁奥氏体化过程及稀土奥贝蠕铁随温度升高时组织的变化。用带有加热装置的万能材料试验等土奥贝蠕铁的各种性能进行了系统测定了如抗拉强度、延伸率、冲吉韧性、热膨胀系数及伸长百分率,结果表明,稀土奥贝蠕铁在室温和高温下均有良好的性能。  相似文献   

19.
利用自行设计组装的以白色发光二极管为光源的表面等离子体子共振传感器实验装置, 检测了不同材质包裹的磁性纳米粒子连接靶向DNA与生物素化DNA探针的结合程度. 结果表明, 与聚苯乙烯磁性微球连接的靶向DNA相比, Fe3O4@SiO2核壳式纳米微球连接的靶向DNA与生物素化的DNA探针结合速率较快, 且其相对标准偏差较小.  相似文献   

20.
Six anion-exchange resins with different properties were compared with respect to detoxification of a dilute-acid hydrolysate of spruce prior to ethanolic fermentation with Saccharomyces cerevisiae. The six resins encompassed strong and weak functional groups as well as styrene-, phenol-, and acrylic-based matrices. In an analytical experimental series, fractions from columns packed with the different resins were analyzed regarding pH, glucose, furfural, hydroxymethylfurfural, phenolic compounds, levulinic acid, acetic acid, formic acid, and sulfate. An initial adsorption of glucose occurred in the strong alkaline environment and led to glucose accumulation at a later stage. Acetic and levulinic acid passed through the column before formic acid, whereas sulfate had the strongest affinity. In a preparative experimental series, one fraction from each of six columns packed with the different resins was collected for assay of the fermentability and analysis of glucose, mannose, and fermentation inhibitors. The fractions collected from strong anion-exchange resins with styrene-based matrices displayed the best fermentability: a sevenfold enhancement of ethanol productivity compared with untreated hydrolysate. Fractions from a strong anion exchanger with acrylic-based matrix and a weak exchanger with phenol-based resin displayed an intermediate improvement in fermentability, a four- to fivefold increase in ethanol productivity. The fractions from two weak exchangers with styrene- and acrylic-based matrices displayed a twofold increase in ethanol productivity. Phenolic compounds were more efficiently removed by resins with styrene-and phenol-based matrices than by resins with acrylic-based matrices.  相似文献   

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