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1.
胶束增敏荧光光谱法测定吡哌酸   总被引:4,自引:0,他引:4  
采用不同表面活性剂对吡哌酸在胶束体系中的荧光性质进行了研究,发现在酸性介质中十二烷基硫酸钠(SDS)对吡哌酸有较强的增敏作用,据此建立了胶束增敏荧光光谱法测定吡哌酸的新方法。方法线性范围为0.07-0.36μg/mL,检出限为0.04μg/mL,平均回收率为98.6%-101.3%,相对标准偏差为1.1%-1.2%。样品测定结果令人满意。  相似文献   

2.
建立了手性柱HPLC法测定盐酸贝那普利的中间体(R)-α-羟基苯丁酸乙酯中的(S)-α-羟基苯丁酸乙酯。采用Chiralcel OD-H色谱柱,流动相正己烷-异丙醇(体积比90:10),流速1.0mL/min,检测波长254nm,进样体积20μL,按外标法以峰面积计算(R)-α-羟基苯丁酸乙酯中的(S)-α-羟基苯丁酸乙酯的含量。(S)体的线性范围5.5~23.8μg/mL,检出限0.47μg/mL(S/N=3),回收率为96%~103%,精密度RSD为2.1%(n=6)。  相似文献   

3.
戈早川  周建明 《分析化学》2004,32(1):99-101
以2%CPC-醋酸乙酯(9:1)胶束溶液为展开剂,在聚酰胺薄膜上成功地分离了小檗碱、巴马汀和药根碱。以345nm为测定波长,550nm为参比波长进行扫描测定,建立了一种新的同时测定黄连及其制剂中小檗碱、巴马汀和药根碱的胶束薄层扫描法。小檗碱、巴马汀和药根碱的线性范围分别为0.2—2.4、0.1—1.0和0.1—1.0μg;回收率分别为97.7%-99.4%、101.7%~102.6%和96.7%-97.8%;相对标准偏差分别为1.4%-1.7%、1.9%-2.7%和1.8%-2.2%。  相似文献   

4.
朱昱  谭家镒  孙毓庆 《分析化学》2003,31(7):850-852
建立了用特丁基二甲基硅烷(TBDMS)衍生化-气相色谱-质谱联用分析尿中硝西泮的主要代谢物7-氨基硝西泮(7ANIZ)的高灵敏方法。方法的样品萃取率为83.6%;线性范围为10~500μg/L;检出限(LOD)为1μg/L;定量限(LOQ)为3μg/L;RSD为3.6%-5.8%,回收率为96.3%-102.6%。对口服10mg硝西泮者96h内所排泄的尿液进行了7ANIZ检测,结果表明:本方法能满足司法鉴定的要求。  相似文献   

5.
DNA荧光探针—荧光素-中性红体系的研究   总被引:5,自引:0,他引:5  
基于DNA对荧光素(FL)-中性红(NR)分子间荧光能量转移的抑制作用,以荧光素-中性红为荧光探针,考察该探针与DNA的结合反应,建立了准确测定DNA的新方法,在pH=6.5条件下,hsDNA、ctDNA和smDNA的浓度与荧光素-中性红体系的荧光比值变化量Δ(Fd/Fa)成线性关系,响应线性范围分别为0.25-6.25μg/mL、0.10-5.00μg/mL、0.10-4.00μg/mL,0.025μg/mL和0.023μg/mL;分析测定了DNA合成样品,回收率91.3%-101.4%,相对标准偏差小于4.2%.  相似文献   

6.
反相高效液相色谱检测丹参药材中4种丹参酮的含量   总被引:6,自引:0,他引:6  
建立了测定丹参药材中4种丹参酮含量的反相高效液相色谱法,色谱条件:流动相为水(含0.5%三乙胺)-甲醇-四氢呋喃(45/55/5,V/V/V),流速为1mL/min;PDA检测波长254m;4种成分丹参酮Ⅰ、丹参酮ⅡA、隐丹参酮和二氢丹参酮的加样回收率在95.1%-101.2%之间,线性范围为0.08-2μg。该方法准确,稳定,重现性好。根据该色谱条件,测定了不同产地的丹参药材,结果表明:该色谱方法准确检测了生药中4种丹参酮的含量,适合于丹参药材的质量控制。  相似文献   

7.
研究了以Co(Ⅱ)络合物为催化剂,α-卤代萘与叔已酮碳负离子的自由基链式亲核取代反应(SRN1)产物α-萘基叔已酮的薄层色谱扫描定量分析方法;定量分析的弭性范围为0-4.4μg,平均回收率99%-101%,异板间相对标准偏差为2.3%,同板相对标准偏差为1.6%。  相似文献   

8.
运用毛细管电泳-电导检测方法对4种四环素衍生物——土霉素(OTC)、金霉素(CTC)、强力霉素(DOC)和四环素(TC)的分离进行了研究。在3.5mmol/L三羟基氨基甲烷(Tris)-7.5mmol/L柠檬酸(Cit)pH4.0的运行缓冲液中,4种四环素衍生物在15min内获得完全分离。四环素衍生物的线性范围分别为5.0-500μg/mL OTC,3.6-420μg/mL CTC,4.5-470μg/mL DOC和2.5-400μg/mL TC。检测限(S/N=3)分别为OTC2.0μg/mL,CTC 1.8μg/mL,DOC2.5μg/mL和TC1.0μg/mL。采用本法对实际样品强力霉素片中强力霉素和土霉素片中土霉素进行测定,回收率分别为97.2%和96.4%。  相似文献   

9.
建立了顶空固相微萃取与毛细管气相色谱法(HS—SPME-GC)测定废水中芳香胺类化合物的新方法。采用溶胶-凝胶法,自制新型单苯并冠醚探针.对萃取温度,萃取时间、解吸时间、离子强度和pH值等实验条件进行了优化选择:结果表明,该方法精密度良好,在标准溶液为0.1mg/L时,相对标准偏差(RSD)为4.0%~7.8%,线性范围为0.05~100μg/L,检出限达到0.005~0.01μg/L,加标回收率在97%~105%之间。运用该法对药厂废水中芳香胺类化合物进行了检测,结果令人满意由此可见,对环境中的芳香胺化合物进行检测,固相微萃取是一种快速、经济、有效的方法。  相似文献   

10.
林旭聪  谢增鸿  郭良洽  陈国南 《合成化学》2003,11(6):499-502,506
由二茂铁经甲酰基化、氧化和酰氯化制备的1,1′-二茂铁二酰氯与对苯二胺和对硝基苯胺缩合反应,合成了新型磷酸盐敏感试剂:1,1′-二[(对苯二胺基)-N-羰基]-二茂铁(L1)和1,1′-二[(对硝基苯胺基)-N-羰基]二茂铁(L),并研究了Ll,L2与磷酸盐阴离子的电子结合性能。Ll,L2对磷酸盐响应灵敏。Ll对H2PO4^-响应的线性为1.00μg/mL~10.00μg/mL,检测限(3σ/k)为0.01μg/mL;也对PO4^3-响应的线性为6.60μg/mL~54.50μg/mL,检测限(3σ/k)为0.03μg/mL。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

19.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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