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1.
离子对高效液相色谱法分析注射用新灭菌   总被引:1,自引:1,他引:1  
建立了离子对高效液相色谱法分离与测定复方制剂(新灭菌)中的羟氨苄青霉素及氟氯青霉素含量法。采用C8.10μm,4.6×200mm柱(大连化物所Spherisorb),以含1.4%十六烷基三甲基溴化铵的pH6.5磷酸盐缓冲液-乙腈(68+32)为流动相,在紫外检测器254nm波长处检测,线性范围为0.25~2mg/mL,r=0.9999(n=5),羟氨苄青霉素及氟氯青霉素平均回收率分别为99.5%及100.7%(n=5)。精密度:羟氨苄青霉素及氟氯青霉素日内(4h)平均RSD(相对标准偏差)均为0.8%(n=15),日间(2h)平均RSD分别为0.6%和0.7%(n=3)。  相似文献   

2.
用含氮,硫功能团的螯合树脂YPA,进行静态吸附,含待测定元素的浓缩物制成悬浮体,采用悬浮体进样/电热蒸发等离子体原子发射光谱(ETV-ICP-AES)直接测定。方法的检出限分别为0.5,0.7和4.0ng/mL(对Pt,Pd和Os)相对标准偏差分别为2.6%,4.7%和3.8%(n=10,Pt:2.0mg/L,Pd:2mg/L,Os:5.0mg/L)。应用本法对质标样进行了分析,测定值与标准值基本  相似文献   

3.
应用ICP-AES、酶氧化反应、酸性非特异性酯酶方法,对33例原发性肝癌患者,测定血清多种微量元素、铜蓝蛋白及T淋巴细胞,分别与17例、36例、34例健康者对照.原发性肝癌组血清铜x±s=19.19±6.708μmol/L)高于对照组(x±S=14.82±4.37μmol/L),血清钼(0.437±0.312μmol/L)、锌(15.51±8.77μmol/L)、铁(20.97±26.13μmol/L)均低于对照组铝(1.186±0.312μmol/L)、锌(20.94±6.31μmol/L)、铁(46.72±29.89μmol/L),P值均<0.05;肝癌组铜蓝蛋白(x±S=5.38±2.35活性单位/mL)高于对照组x±S=3.92±0.87活性单位/mL,P<0.05;T淋巴细胞(x±S=57.78±11.71活性单位/mL),低于对照组(x±S=66.80±12.82活性单位/mL),P<0.05.结果提示原发性肝癌微量元素代谢异常,直接影响酶系统,使自由基失控、机体内促氧化和抗氧化平衡失调,估计这一学说在肝癌的发病中起重要作用。  相似文献   

4.
林振光  庄鸿辉 《结构化学》1996,15(3):199-204
环己酮与硫代碳酰肼在不同介质中的反应,合成出两个不同的环己烷螺含氮杂环化合物。经X-射线结构分析确定它们分别为1,2,4,5-四氮螺[5,5]十一烷-3-硫酮,C_7H_(14)N_4S(Ⅰ)和1,2,4,-三氮螺[4,5]癸-1-烯-4-氨基-3-硫酮。C_7H_(12)N_4S_x(S_x=0.8S+0.2O)(Ⅱ)。晶体学参数分别为(Ⅰ):P2_1/c,a=12.026(4),b=26.817(6),c=12.042(3),β=115.94(2)°,Z=4,V=933.4(10),M_r=186.28;(Ⅱ):P2_1/m,a=6.595(7),b=6.817(6),c=10.572(6),β=106.3(1)°,V=456(1),Z=2,M_r=181.05。最终一致因子分别为R=0.054,R_w=0.065和R=0.089,R_w=0.096。两个化合物中,环己烷都为椅式构型,它与其螺联的6员氮杂环,5员氮杂环的最小二乘平面间的夹角分别为68.94和90°。并对合成反应途径作了初步讨论。  相似文献   

5.
宋俊峰  高雅芳 《分析化学》1995,23(4):438-441
本报道一种测定哌仑西平的单扫描示波极谱法,在0.1mol/LNH4Cl-NH3.H2O(pH8.0±0.1)缓冲液中,哌仑西平有一极谱还原波,其峰电位为-1.51V(vs.SCE),其一阶导数峰高与哌仑西闰浓度在6.6×10^-7-4.6×10^-6mol/L(r=0.9981)和6.6×10^-6-1.6×10^-5mol/L(r=0.9991)范围内有线性关系,检测限为3.4×10-7mol  相似文献   

6.
陈寿山  滑艳玲 《结构化学》1994,13(3):211-215
报道了双(1-正戊基环己基茂)二氯化钛[(η5-C5H4C(CH2)5(C5H11-n]2TiCl2(I)及双(1-甲基-1-(α-噻吩基)乙基环戊二烯基)二氯化钛[η ̄5-C5H4C(CH3)_2-]2TiCl2(Ⅱ)的晶体结构和分子结构。二者均系单斜晶系,(I)的空间群为P2/n,晶胞参数a=14.180(2),b=6.562(1),c=17.046(3),β=99.63(1)°,Z=2,V=1563.8,Dx=1.188g/cm3,F(000)=596,Mr=553.56,λ=0.71073μ=4.59cm-1,R=0.058,Rw=0.066;(1)的空间群为C2/c,晶胞参数a=25.713(1),b=6.617(1),c=13.591(1),β=92.78(2)°,Z=4,V=2309.8,Dx=1.430g/cm3,Mr=497.41,λ=0.71073,μ=7.822cm-1,F(000)=1032,R=0.055,Rw=0.072。茂环上取代基对茂环金属化合物的结构产生较大影响,空间阻碍的增大使得取代基与茂环相连C-C单键增长。  相似文献   

7.
用硫酸铈接触法对哈尔滨市动力区(1992年)和呼兰县(1993年)的居民末稍碘盐和碘盐加工点销售点碘盐共232份盐样进行了测定分析,其结果:动力区居民末稍盐n=76,x±SD=19.58±12.86;碘盐销售点,n=77,x±SD=20.599±20.174.呼兰县居民末稍盐n=75,x±SD=8.89±5.91;加工点n=19,x±SD=46.08±38.93;销售点,n=4,x±SD=20.75±17.70.平均回收率为98%.  相似文献   

8.
研究了6-硝基喹啉在滴汞电极上的电极过程并建立了它的单扫示波极谱测定。在0.10mol/LNaCl底液中,6-硝基喹啉的二阶导数阴极波峰电流i"p(E"p=-0.66VvsSCE)浓度在1.0×10^-7-2.5×10^-5mol/L范围内有良好线性关系,检出限为4.2×10^-8mol/L,RSD=1。7%(n=6)。此外还考察了多种人体内常见微量物质及表面活性剂对i"p的影响。  相似文献   

9.
碘酸钾存在下极谱催化波法测定陈皮甙   总被引:2,自引:0,他引:2  
过玮  何盈盈  许昭  宋俊峰 《分析化学》2002,30(2):202-203
基于陈皮甙在KIO3存在下产生的极谱催化波,拟定了测定陈皮甙的新方法。在 0.55 mol/L HAc-0.01mol/L NaAc(pH 4.00±0.05)-1.0×10~(-3)mol/L KIO3缓冲溶液中,陈皮甙催化波的峰电位为-1.35 V(vs,SCE),它的一阶导数峰峰电流与陈皮甙浓度在2.6 × 10~(-7)~2.6 × 10~(-6)mol/L范围内呈线性关系(r=0.9970,n=6)。本方法比现有的电化学方法灵敏度高一个数量级。可用于直接测定中草药贯众水提液中陈皮甙含量。  相似文献   

10.
大黄酚在0.15mol/L HAc-NaAc(pH4.9)底液中,出现一灵敏的示波极谱导数峰,峰电位为-0.45V(vs,SCE),峰电流与大黄酚浓度在2.0×10^-7-5.0×10^-6mol/L范围内成线性关系,检测限为2.0×10^-6mol/L。用于生药大黄中大黄酚的测定,回收率为92.4%-108.4%。用多种电化学手段研究体系的电化学行为,测得电极反应电子数n=2。体系具有吸附性,并  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.
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   

14.
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   

15.
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   

16.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

17.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

18.
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   

19.
Siqi Li  Xingpeng Chen  Jiaxi Xu 《Tetrahedron》2018,74(14):1613-1620
Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular SN2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.  相似文献   

20.
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   

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