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诺氟沙星的交流示波极谱滴定法研究 总被引:1,自引:2,他引:1
本文报道了示波极谱滴定法测定诺氟沙星的含量。用PH4.4的HAc-NaAc缓冲溶液溶解药样,并与过量的四苯硼钠作用生成沉淀。过滤后,用硫酸亚铊回滴过量的Na-TPB,由示波极谱图[dE/dt=f(E)]上TPB切口的消失指示滴定络点,进而在该溶液中进行空白实验。 相似文献
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本文报道了铜合金中铜的示波滴定方法。样品酸溶后,用抗坏血酸还的Cu^2+为Cu^+,加入过量的四苯硼钠,在PH5-6的HAc-NaAc缓冲溶液中,定量形成Cu-TPB沉淀,过量的TPB^-,以Tl^+标准溶液进行示波滴定,铜合金中共存元素不干扰测定。铜的测定回收率99.8%-100.1%。进行了多种铜合金中铜含量的测定,结果令人满意。 相似文献
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烃铵盐用于示波极谱滴定法测定诺氟沙星 总被引:3,自引:0,他引:3
本文报道了以烃铵盐为滴定剂,用交流示波极谱四苯硼钠(Na-TPB)滴定法测定诺氟沙星(NFX)的含量。应用于胶囊样品的测定,与药典法测得结果基本一致,最大相对误差≤0.56%,最大RSD为0.29%,平均回收率为100.6%。 相似文献
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交流示波极谱滴定法测定氟哌酸 总被引:2,自引:1,他引:2
交流示波极谱滴定法测定氟哌酸李彦威,宣春生,刘悦红,高惠文(太原工业大学应用化学系,太原,030024)(太原制药厂)关键词交流示波极谱,示波滴定,氟哌酸氟哌酸(FPA)在酸性溶液中能与四苯硼钠(N3-TPB)发生缔合反应,生成白色沉淀,过量的Na-... 相似文献
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乳酸环丙沙星的示波极谱滴定 总被引:1,自引:1,他引:0
1引言 乳酸环丙沙星(CPRL)为第三代氟喹诺四类抗生素,目前,其含量的测定主要有非水滴定法、紫外分光光度法、HPLC、极谱法等,但未见有示波极谱滴定法的报道。本法用四苯硼钠(Na-TPB)作沉淀剂,在弱酸性(pH=5.1)条件下与乳酸环丙沙星作用生成沉淀,过滤后,用硫酸亚铊标准溶液回滴滤液中过量的Na-TPB,以TPB在示波极谱图[dE/dt=f(E)]中的切口消失指示滴定终点。本法仪器简单,操作方便,取样量小,图形直观,终点敏锐,用于原料药样品的测定有良好的准确度和重现性,其结果与非水滴定法… 相似文献
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交流示波极谱滴定法测定吡哌酸 总被引:8,自引:0,他引:8
本文介绍用交流示波极谱滴定法测定吡哌酸的含量。在HCl-NaAc缓冲溶液中,加入过量的Na-TPB与吡哌酸作用生成沉淀,过滤后用亚铊标准溶液定滤液中过量的TPB,由交流示波极谱图上TPB的切口消失指示终点。本法操作简便,终点直观,应用于原料药样品的测定,并与药典法相对照,结果基本吻合。 相似文献
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在pH=5.0的HAcNaAc介质中,Nb(Ⅴ)与1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5(PMBP)生成络合物,于一0.96V(vs.SCE)出现一尖极谱波。在滴汞电极上用示波极谱仪或在悬汞电极上则吸附伏安曲线。峰电流与Nb(Ⅴ)浓度分别在0.0075-0.80μg/mL及0.000075-0.0075μg/mL范围内呈线性关系。实验 3 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
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
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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
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
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用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
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Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT). 相似文献
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George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine. 相似文献