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61.
Pyrrolyl and thienyl derived sulfonamides and their metal [cobalt(II), copper(II), nickel(II) and zinc(II)] complexes were synthesized and characterized by elemental analyses, molar conductances, magnetic moments, IR, 1H NMR, 13C NMR and electronic spectral data. These compounds were screened for in‐vitro antibacterial activity against four Gram‐negative (Escherichia coli, Shigella flexeneri, Pseudomonas aeruginosa and Salmonella typhi) and two Gram‐positive (Bacillus subtilis and Staphylococcus aureus) bacterial strains, and for in‐vitro antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies revealed that all compounds showed significant to moderate antibacterial activity; however, the zinc complexes were shown to be the most active against various species. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic properties of all the synthesized ligands and their metal complexes. Only two compounds ( 14 and 19 ) displayed potent cytotoxic activity as LD50 = 5.5637 × 10?4 and 4.4023 × 10?4 M ml?1 respectively, against Artemia salina. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
62.
建立了同时测定化妆品中22种磺胺类药物(磺胺胍、磺胺、磺胺嘧啶、磺胺二甲异嘧啶、磺胺醋酰、磺胺噻唑、磺胺吡啶、磺胺甲基嘧啶、磺胺对甲氧嘧啶、磺胺二甲噁唑、磺胺二甲嘧啶、磺胺甲噻二唑、磺胺甲氧哒嗪、琥珀酰磺胺噻唑、磺胺氯哒嗪、磺胺甲基异噁唑、磺胺间甲氧嘧啶、磺胺邻二甲氧嘧啶、磺胺二甲异噁唑、磺胺间二甲氧嘧啶、磺胺喹噁啉、磺胺硝苯)的超高效液相色谱-串联质谱分析方法。膏霜、水剂、散粉、香波、唇膏等不同类型的化妆品样品经超声提取后,以Waters ACQUITY UPLC BEH C18色谱柱(50 mm×2.1 mm,1.7μm)分离后进行UPLC/MS/MS多反应监测模式下的定性及定量分析。22种磺胺类药物的方法检出限为3.5~14.1μg/kg;在低、中、高的3个添加水平范围内的平均回收率为80.3%~103.6%;日内精密度均小于12%,日间精密度均小于15%。  相似文献   
63.
64.
We have observed product ee's that begin at 20% at low reaction conversion and rise to 79% ee at the completion of the reaction in the asymmetric addition of alkyl groups to benzaldehyde. This rare behavior is attributed to autoinduction, in which the catalyst evolves by incorporation of the product. Based on this, we have been able to optimize the catalyst by variation of achiral, rather than enantiopure ligands.  相似文献   
65.
报道以CuSO4作沉淀剂,DDTC(二乙基二硫代氨基甲酸钠,铜试剂)为滴定剂,NaAc为极谱底液,采用交流示波极谱滴定法测定呋喃苯胺酸,乙酰唑胺二种磺酰胺类药物制剂的含量,该法快速,简便,终点直观回收率实验获得满意结果。  相似文献   
66.
Conditional cleavage : Photochemical S? N bond cleavage of the Zn2+ complex of N‐dansylcyclen (ZnL2) in aqueous solution was investigated. Moreover, photolysis of ZnL2 (see scheme) facilitated photoreversion of cis,syn‐thymine photodimer (T[c,s]T).

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67.
刘培勇  张惠  米之金  张良成  张光仁 《色谱》2019,37(10):1098-1104
建立了猪肉中11种常见的磺胺类兽药残留的两步液液萃取-固相萃取净化-高效液相色谱-串联质谱(LC-MS/MS)检测方法。猪肉样品经乙酸乙酯(含2%(v/v)甲酸)及丙酮分两步液液萃取,正己烷脱脂,Oasis MCX混合阳离子固相萃取小柱净化,氮吹浓缩,定容,过滤膜后进行高效液相色谱-串联质谱分析。采用多反应监测正离子模式进行检测,以基质校准曲线外标法定量。结果表明,在20~400 μg/L范围内11种磺胺类药物均呈现良好的线性关系(相关系数(r2)≥ 0.99),检出限(LODs)(S/N=3)和定量限(LOQs)(S/N=10)分别为0.1~1.0 μg/kg和0.2~3.0 μg/kg。对阴性猪肉样品,在50、100、200 μg/kg 3个水平下分别进行加标回收试验,测得各待测物的平均回收率为79.3%~105.5%之间,相对标准偏差为1.3%~11.6%(n=6)。该方法比采用一步液液萃取法具有更高的提取效率,同时结合固相萃取净化方法进一步富集目标化合物,降低了基质干扰,提高了检测灵敏度。  相似文献   
68.
A detailed study of the rearrangement of five cycloalkene N-toluenesulfonyl (tosyl) aziridines using sec-butyllithium (with and without added ligands such as (−)-sparteine and TMEDA) has been carried out. Allylic sulfonamides were the main products from the cyclopentene and cyclohexene aziridines whereas bicyclic sulfonamides were obtained from the cycloheptene and cyclooctene aziridines. In most cases, p-toluenesulfonamide (TsNH2) was produced as a by-product and a mechanistic explanation for its formation is forwarded. These reactions are believed to involve α-lithiation to a lithiated aziridine which can then partition through two pathways: (i) rearrangement to allylic or bicyclic sulfonamides via C-H insertion reactions or (ii) reductive alkylation to alkenes via attack by sec-butyllithium and subsequent elimination of TsNH2. In the (−)-sparteine reactions, the products were generated with 38-66% ee and the sense of asymmetric induction involved lithiation of the S-aziridine stereocentre. This is opposite to that observed with epoxides.  相似文献   
69.
Crystal structures of 4-[(3,5-dibromo-2-hydroxy-benzylidene)-amino]-benzenesulfonamide (I), 4-[(3,5-dibromo-2-hydroxy-benzylidene)-amino]-N-thiazol-2-yl-benzenesulfonamide (II), and 4-[((3,5-dibromo-2-hydroxy-benzylidene)-amino]-N-(5-ethyl-1,3,4-thiadiazol-2-yl)-benzenesulfonamide (III) have been determined. The crystals of I are monoclinic, a = 8.645(2) Å, b = 12.622(3) Å, c = 14.414(3) Å; β = 104.31(3)°, space group P21/n, Z = 4, R = 0.0642. The crystals of II are also monoclinic, a = 10.313(2) Å, b = 11.288(2) Å, c = 15.766(3) Å; α = 99.37(3)°, space group P21/c, Z = 4, R = 0.0635. The crystals of III are triclinic, a = 10.567(2) Å, b = 10.849(2) Å, c = 18.432(4) Å; α = 75.97(3)°, β = 89.71(3)°, γ = 87.33(3)°, space group P-1, Z = 4, R = 0.0644. The asymmetric part of the unit cell of compounds I and II contains a single molecule of the Schiff’s base, while in III two independent azomethine molecules A and B. The studied compounds I–III adopt the E-configuration relatively to the double azomethine bond C=N. Owing to phenolic oxygen together with nitrogen and oxygen atoms of the sulfonamide group, compound I makes in a crystalline state a two-dimensional hydrogen bonded network parallel to the plane (1 0 1). Compound II forms centrosymmetric dimers in the crystals via N-H…N hydrogen bonds. These dimers, in their turn, are connected by hydrogen bonds O-H…O into infinite chains running along the double screw axis b. As in II, molecules and of compound III form centrosymmetric dimers through hydrogen bonding N-H…N. These dimers are linked into infinite chains running along the c axis by hydrogen bonds C-H…O. The π-π-stacking interaction of aromatic rings is observed in all the compounds studied.  相似文献   
70.
Abstract

Some derivatives of thieno[2,3-d]pyrimidine containing amino acids 3a-i, imidazoles 4a-f, isothiocyanate 5, thiourethane 6, triazine 8, pyrimidine 10, sulphonamides 13a-d, 14, pyrazole 16 and pyrazolone 17 were synthesized. The structural assignments of the new compounds were based on analytical, spectroscopic measurements and chemical reactions. Some of the obtained compounds showed interesting antimicrobial activities.  相似文献   
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