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1.
李焰  田娟  黄锦霞 《有机化学》2002,22(1):52-55
2-甲基-4-庚醇和2-甲基-4-辛醇是西印度蔗螟(Metamasiushemipterus)聚集信息素的次要组份,本文以天然产物(S)-亮氨酸为原料合成出了2-甲基-4-庚醇及2-甲基-4-辛醇的所有对映异构体,其关键步骤是由(2S)-4-甲基-1,2-戊二醇合成出(2S)和(2R)-4-甲基-1,2-环氧戊烷两种重要中间体,目标产物光学纯度可达95%以上。  相似文献   

2.
付博  张吉苹  姜晖  周璐 《色谱》2016,34(9):895-900
建立了基于脂肪酸的漂浮液滴固化分散液液微萃取(FA-DLLME-SFO)方法,与高效液相色谱联用检测了酒类样品中的4-乙基苯酚和4-乙基愈创木酚。该方法萃取时间仅需4 min,仅需脂肪酸、氨水和硫酸3种对环境友好的试剂。对影响方法萃取效率的因素(包括样品的体积、萃取剂的种类和用量、氨水和硫酸的体积以及盐的加入量)进行了详细的考察。在最佳萃取条件下(10 mL样品,100 μL辛酸萃取剂,110 μL 25%~28%(质量分数)的氨水,0.8 mL 98%(质量分数)的浓硫酸,3.0 g NaCl),4-乙基苯酚和4-乙基愈创木酚在0.02~1.0 mg/L范围内呈良好的线性关系,相关系数分别为0.9997和0.9999,相对标准偏差(n=3)分别为6.2%和3.5%,检出限分别为6.33和5.81 μg/L,富集倍数分别为79和86。在啤酒和白葡萄酒样品中,加标回收率为81.4%~108.7%,相对标准偏差(n=3)小于8.9%。该方法简单、对环境友好,可用于酒类样品中4-乙基苯酚和4-乙基愈创木酚的检测。  相似文献   

3.
首次以H4SiW12O40 * 22H2O和(NH4)2C2O4 * H2O为原料,室温固相反应合成出(NH4)4SiW12O40纳米微粒;用元素分析、 FTIR确定产物的组成和结构; XRD、 TEM和BET对产物的形貌、晶粒尺寸和比表面积进行了表征; TG-DTA确定了产物的稳定温区.结果表明,产物为纳米粒子,平均粒径为60 nm,比表面积为108.7 m2/g,在430℃以下具有良好的热稳定性.在固相反应中,研磨和放热反应热效应能加快反应物扩散速率和生成物成核速率,使产物粒径减小;反应物含有结晶水和生成物H2C2O4 * 2H2O,对形成小粒径的(NH4)4SiW12O40纳米粒子起关键作用.  相似文献   

4.
将4-硝基邻苯二甲酰亚甲胺(4-NPI)用铁粉还原为4-氨基邻苯二甲酰亚甲胺 ,再在氢氧化钠水溶液中水解成4-氨基邻苯二甲酸钠。4-氨基邻苯二甲酸钠在氢溴 酸中经Sandmeyer反应合成4-溴代苯酐。产品纯度高,是合成4-溴代苯酐的一个比较 理想的方法。  相似文献   

5.
片螺素(Lamellarins)是一类从海洋软体动物中提取的具有良好生物活性的吡咯类生物碱.自1985年,Faulkner等首次从前腮亚纲软体动物中提取出片螺素A-D[1]后,国内外便开始对各类片螺素及其衍生物的全合成进行研究,至今相关合成报道络绎不绝[2][3].与此同时多种开链片螺素也是一类具有特殊生物活性的吡咯类生物碱,由于目前还未有关其提取的报道,因此对其进行合成具有重要意义.  相似文献   

6.
以四-(4-甲氧基-3-磺酸基苯)卟啉(T(4-Mop)PS4)为探针,通过T(4-Mop)PS4与牛血清白蛋白(BSA)的相互作用,建立了测定BSA的电化学分析方法。T(4-Mop)PS4的峰电流变化(ΔIp)与BSA在2.0×10-6~1.0×10-5mol.L-1范围内呈良好的线性关系,检出限为1.2×10-6mol.L-1;对5.0×10-6mol.L-1BSA平行测定8次,其相对标准偏差为2.0%,回收率为95%~104%。组氨酸、缬氨酸、苯丙氨酸、丝氨酸、异白氨酸、谷氨酰胺、苏氨酸等氨基酸对BSA的测定不产生干扰。采用紫外可见光度法、荧光光谱法和线性扫描伏安法(LSV)研究了T(4-Mop)PS4与BSA之间的相互作用,并测定了二者相互作用的结合常数和结合比。研究表明,T(4-Mop)PS4与BSA之间主要以疏水作用力结合,形成了1∶1的稳定复合物。  相似文献   

7.
采用(NH4)2SO4溶液浸渍法制备了一系列SO2-4/SnO2催化剂(Cat-n,n=5,10,15,20),其结构经IR表征.以Cat-10(焙烧温度500℃)催化苯液相硝化反应的研究结果表明,引入SO2-4后催化剂的活性显著增加,硝基苯产率63.8%.  相似文献   

8.
Poly(4-vinylpyridinium tribromide) was prepared from poly(4-vinylpyridin) and used for the selective oxidation of a variety of sulfides to the corresponding sulfoxides.The oxidation reaction was carried out heterogeneously in acetone/water,as green solvent, at room temperature.  相似文献   

9.
1,1-Bis[4-(4-carboxyphenoxy)phenyl]cyclohexane (III) and 1,1-bis[4-(4-aminophenoxy)phenyl]cyclohexane (V) were prepared in two main steps starting from the aromatic nucleophilic substitution of p-fluorobenzonitrile and p-chloronitrobenzene, respectively, with 1,1-bis(4-hydroxyphenyl)cyclohexane in the presence of potassium carbonate in N,N-dimethylformamide (DMF). Using triphenyl phosphite and pyridine as condensing agents, two series of polyamides with cyclohexylidene cardo groups were directly polycondensated from dicarboxylic acid III with various aromatic diamines or from diamine V with various aromatic dicarboxylic acids in an N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride. The polyamides exhibited inherent viscosities in the range of 0.45 to 1.78 dL/g. Almost all of the polymers were readily soluble in polar aprotic solvents such as NMP and N,N-dimethylacetamide (DMAc) and could afford transparent, flexible, and tough films by solution casting. The glass transition temperatures (Tg) of these aromatic polyamides were in the range of 180–243°C by DSC, and the 10% weight loss temperatures in nitrogen and air were all above 450°C. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3575–3583, 1999  相似文献   

10.
Proteolysis targeting chimeras(PROTACs) are bispecific molecules containing a target protein binder and a ubiquitin ligase binder connected by a linker. Recently, some heterobifunctional small molecule bromodomain-containing protein 4(BRD4) degraders based on the concept of PROTACs were designed to induce the degradation of BRD4 protein. Herein, we synthesized a new class of PROTAC BRD4 degraders. One of the most promising compound 22f exhibited robust potency of BRD4 inhibition with IC50 value of (9.4±0.6) nmol/L. Furthermore, compound 22f potently inhibited cell proliferation in BRD4-sensitive cell lines RS4;11 with IC50 value of (27.6±1.6) nmol/L and capable of inducing degradation of BRD4 protein at 0.5―1.0 μmol/L in the RS4;11 cells. These data establish that compound 22f is a potent and efficacious BRD4 degrader.  相似文献   

11.
Three new chromophores with triphenylamine as molecular focal point bearing one,two, or three 4-(n-butyloxystyryl) group(s) at the periphery respectively, (named as T1, T2, and T3) have been synthesized and characterized. It is interesting to find that the fluorescence quantum yield increases from T1 (0.489), to T3 (0.535), and to T2 (0.628) in cyclohexane, meanwhile the lifetime for T3 is shorter than T1 and T2, which is an important characteristic for applications in light emitting diode. Also PMMA (polymethyl methacrylate) film doped with T3 gives stronger fluorescence than T1, and T2. Cyclic voltammetry showed that T3 exhibited lowest oxidation potential of-0.52 V vs SCE, suggesting its better hole-transport property.  相似文献   

12.
Summary: A general method of measurement of polymer hydrogen bond (HB) cooperativity using a low-molecular weight model ligand named marker and two independent methods of 2H NMR is presented. As marker, a deutero-compound chemically similar to the functional groups of one of the polymers is used, e.g. pyridine-d5 in the investigated interaction of poly(4-vinylpyridine) with poly(4-vinylphenol) or acetic acid-d4 in the interaction of polyacrylic acid with poly(4-vinylphenol) reported here. The method is based on the fact that a substantial fraction of the marker, originally bound to the groups of one of the polymers, is liberated by the cooperative interaction between the two polymers. For the establishment of the fraction of the bound marker before and after mixing the polymers, 2H NMR quadrupolar relaxation or 2H PFG NMR diffusion measurement can be used with comparable precision. In both these methods, the results must be normalized to a standard viscosity using the relaxation or diffusion of an added inert compound such as CDCl3.  相似文献   

13.
A comparative study of some quantitative methods has been undertaken. Chemical and colorimetric procedures have been developed for the determination of IS4: 4-(anisylideneamino) antipyrine. The non-aqueous titration and the nitritometric techniques were used. The formation of colored azo dye derivatives through diazotization and coupling with phenolic and amine reagents has been the basis of the colorimetric determination. Statistical analysis of the results has shown that a good agreement of the results has been found on applying the proposed methods to 4-aminoantipyrine.  相似文献   

14.
新型多取代硫代半卡巴腙类配体的合成与结构表征   总被引:2,自引:0,他引:2  
赵文献  赵明根 《有机化学》2001,21(9):681-684
为发展金属离子配体,设计合成了一系列新型多取代氨基硫脲。烯丙基异硫氰酸酯与水合肼溶液反应,制得4-烯丙基氨基硫脲(1)。1分别与联乙酰(2,3-丁二酮)、水合茚三酮、乙二醛反应,合成出联乙酰双缩(4-烯丙基氨基硫脲)(2)、茚三酮-1,3-二缩(4-烯丙基氨基硫脲)(5)、乙二醛二缩(4-烯丙基氨基硫脲)(6)。联乙酰和氨基硫脲反应制备出联乙酰双缩氨基硫脲(3),环己酮与1在无水乙醇中回流反应合成出环己酮缩(4-烯丙基氨基硫脲)(4)。缩合反应操作简便,条件温和,反应时间只需0.5~2h,产物收率达到70%~87%。这些化合物均未见报道,其结构通过元素分析,IR、^1HNMR和MS进行鉴定。初步测试了它们对金属离子的配位性能,这些多取代氨基硫脲配体很容易与Cu^2^+、Co^2^+、Ni^2^+、Zn^2^+、Ag^+、Hg^2^+、Hg^2^+~2及稀土离子形成稳定的螯合物。  相似文献   

15.
The formation of the complex between 4-cyanopyridine and 4-(6-acryloyloxy-hexyloxy) benzoic acid and its polymeric analog proceeds due to the proton transfer with the H-bond formation. The presence of two proton acceptor groups within one molecule provides a strong shift of the electron density along the complex molecule due to the conjugation within the proton acceptor molecule. The dielectric relaxation process in a symmetric associate experimentally observed is explained as a kinetic effect related to the formation and destruction of the associate.

Transition from a monomer to a polymer proton donor leads to the formation of the characteristic 1:1 complex with SmC layered structure different from that of a polymer itself.  相似文献   


16.
Some novel (diorgano)chloro(4-chlorobutoxy)silanes were obtained by the reaction of dichlorodiorganosilanes with tetra hydrofuran in the presence of chloroplatinic acid.Translated fromIzvestiva Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 943–945, April, 1996.  相似文献   

17.
本文研究了新显色剂5-(对硝基苯偶氮)-8-(对甲苯磺酰氨基)喹啉(NPTSQ)与铂(Ⅱ)的显色反应。在强碱性介质中,NPTSQ与Pt(Ⅱ)形成1:2的紫蓝色络合物,λ_(max)=640nm,摩尔吸光系数为1.37×10~5L·mol~(-1)·cm~(-1)。铂量在0~25μg/25mL范围内遵守比尔定律。用于冶金氧化渣及铂催化剂中微量铂的测定,结果良好。  相似文献   

18.
The Willgerodt-Kindler reaction of acetophenone was studied.Apart from the normal product 4-(benzylthio-carbonyl)morpholine,another product 4-(benzoylthiocarbonyl)morpholine was obtained unexpectedly.The struc-ture of the latter was confirmed by IR,~1H NMR spectra and X-ray diffraction analysis.The mechanism of the reac-tion was discussed.  相似文献   

19.
Contributions to the Chemistry of Phosphorus. 236. On Several Physical and Chemical Properties of Diphosphane(4) The density of diphosphane(4) has been measured between ?78°C and +18°C and the value d420 = 1.014 · 0.002 extrapolated. The refractive index of P2H4 was determined to be n20 = 1.66 ± 0.01. The surface tension at 0°C and ?50°C was measured to be σ = 34 and 42 dyn · cm?1, respectively. In the UV absorption spectrum, gaseous P2H4 exhibits a broad absorption band at λmax = 2 220 Å, in n-hexane solution, this band is shifted somewhat to shorter wave-lengths. The molar extinction coefficient was determined to be ? ≈? 900 1 · mol?1 · cm?1. As a result of photolytic decomposition, absorptions for PH3 and more phosphorus-rich hydrides also occur. The solubility behavior of P2H4 in various organic solvents and the stabilities of the resultant solutions have been investigated. At 0°C, the solubility of diphosphane(4) in water was found to be ± 035 ± 0.003 g P2H4/100 g solution and that of water in diphosphane(4) to be 43.2 ± 1.6 g H2O/100 g solution. The system diphosphane(4)/methanol also exhibits a miscibility anomaly. The IR spectra of liquid P2H4 and of its solutions in various solvents revealed, in accord with the results of nuclear magnetic resonance spectroscopy [7], that diphosphane(4) is practically not associated. Weak interactions through hydrogen bridging bonds occur with pyridine and methanol in which P2H4 serves as the proton donor and, in the latter case, also as proton acceptor. For the thermolysis of diphosphane(4), it has been found that the primary step comprises a disproportionation with inter-molecular elimination of PH3 and formation of triphosphane(5). With further progress of the thermolysis, in dependence on the reaction conditions, mixtures of various phosphanes of differing composition are formed. Photolysis gives rise to phosphane mixtures having similar compositions. With aqueous silver salt and iodine solutions, diphosphane(4) reacts as a reducing agent; with sodium hydroxide solution, it reacts by a slow disproportionation as well as by formation and degradation of the subsequently formed polyphosphides. On reaction with triphenylmethyl, triphenylmethane and a yellow solid of varying composition are formed. The reaction of diazomethane with diphosphane(4) leads to the preferential insertion of the carbene in the P? P bond and formation of methylenebis(phosphane).  相似文献   

20.
研究了表面活性剂十二烷基苯磺酸钠(SLS) 存在时,meso 四( 对三甲胺基苯基) 卟啉[T(4 TMAP)P] 与铜的显色反应。在pH= 3 .7 的HAc NaAc 介质中,在SLS存在下,铜与[T(4 TMAP)P] 形成1∶2 的稳定配合物,至少在4 .5h 内吸光度无变化。最大吸收波长位于410nm ,ε= 3 .79 ×105L·mol- 1·cm - 1 。铜在0 ~1 .40μg/25mL内有良好线性关系。用于自来水及湖水中铜的测定,相对标准偏差小于3 % ,加标回收率在98 % ~103% 之间  相似文献   

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