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91.
Reported here is a simple and practical functionalization of primary sulfonamides, by means of a pyrylium salt (Pyry‐BF4), with nucleophiles. This simple reagent activates the poorly nucleophilic NH2 group in a sulfonamide, enabling the formation of one of the best electrophiles in organic synthesis: a sulfonyl chloride. Because of the variety of primary sulfonamides in pharmaceutical contexts, special attention has been focused on the direct conversion of densely functionalized primary sulfonamides by a late‐stage formation of the corresponding sulfonyl chloride. A variety of nucleophiles could be engaged in this transformation, thus permitting the synthesis of complex sulfonamides, sulfonates, sulfides, sulfonyl fluorides, and sulfonic acids. The mild reaction conditions and the high selectivity of Pyry‐BF4 towards NH2 groups permit the formation of sulfonyl chlorides in a late‐stage fashion, tolerating a preponderance of sensitive functionalities.  相似文献   
92.
Pyrrolobenzosulfonamide, indolobenzosulfonamide and carbazolobenzosulfonamide derivatives with different acceptor groups were synthesized and their photophysical properties were compared. The electron donor linking sites are found to influence the emission characteristics of these compounds while acceptor linking sites have no noticeable effects on the spectral properties. P2-A5 which is a C-C linked pyrrole derivative exhibited different spectral properties from the C-N linked pyrrole derivatives. The complexation properties of the molecules were also investigated employing Na (I), Ca (II), Li (I), Mg (II), Zn (II) and Cu (II) ions.  相似文献   
93.
《Comptes Rendus Chimie》2017,20(8):833-840
The surface of nanosized fumed silica (FSi) was modified with different amine groups by the use of silylating agents. The obtained propylamine, propylpiperazine, and propyl-p-phenylenediamine–modified FSi were treated with different sulfonyl chlorides to gain sulfonamide-modified FSi compounds. These compounds were characterized by various techniques including Fourier transform infrared spectroscopy, thermogravimetric analysis, differential thermal analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (EDX), confirming the grafted sulfonamides on the FSi surface. Sulfonamide-modified surfaces are efficient catalysts for the Michael addition-based syntheses and coupling reactions. Furthermore, the antibacterial tests showed that these modified FSi compounds have antibacterial activities and thus are useful materials for preparing antibacterial silicone-based compounds such as silicone glue and oil.  相似文献   
94.
结合QuEChERS前处理技术,提出了测定鱼肉中22种磺胺类残留的超高效液相色谱-串联质谱法。样品用含0.1%(体积分数,下同)甲酸的乙腈溶液提取后,经QuEChERS试剂盒净化。净化液在Agilent ZORBAX Eclipse Plus C18色谱柱上分离,以0.1%甲酸溶液-甲醇为流动相进行梯度洗脱。采用电喷雾正离子源及计划式多反应监测模式进行测定,以内标法定量。磺胺硝苯、磺胺、磺胺喹噁啉的线性范围为0.5~50μg·L-1,检出限(3S/N)为0.5μg·L-1;其他19种磺胺类兽药的线性范围为0.1~50μg·L-1,检出限(3S/N)为0.1μg·L-1。加标回收率在78.2%~118%之间,测定值的相对标准偏差(n=6)在3.4%~19%之间。方法用于鱼肉中多种磺胺类药物残留的快速测定,结果与标准方法测定结果一致。  相似文献   
95.
A convenient synthesis method of antisepsis agent TAK-242 ((R)-1) through diastereomeric resolution was developed. By condensation of racemate rac-1 with chiral acid (S)-O-acetylmanderic acid (6a), the desired diastereomer 5a was isolated with 98% de in 39% yield by simple crystallization. Deacylation of 5a with aq NaOH followed by recrystallization provided (R)-1 with 99% ee in 20% yield from rac-1.  相似文献   
96.
固相萃取-HPLC法测定蜂蜜中残留的10种磺胺类药物   总被引:12,自引:0,他引:12  
研究了用固相萃取-高效液相色谱法同时测定蜂蜜中10种磺胺类药物残留量的方法。样品经三氯甲烷溶液提取,过Oasis HLB C18固相萃取柱净化,用乙腈洗脱10种磺胺,反相高效液相色谱-紫外检测器测定。检测波长为270nm,柱温45℃.流动相:磷酸水溶液-乙腈梯度洗脱.该方法前处理简单,梯度洗脱分离效果和重现性好,在0.010~1.0mg/kg添加水平,10种组分的回收率在86.5%~100.8%之间,室内相对标准偏差在3.5%~8.1%之间,线性范围为0.010~10μg/mL,检出限为0.005mg/kg。该方法快速、灵敏、专属,可用于食品中磺胺类药物残留量的常规检测。  相似文献   
97.
应用4株磺胺二甲基嘧啶(SMZ)多克隆抗体和5种不同结构的荧光标记物(Tracer)建立了荧光偏振免疫分析(FPIA)检测SMZ的方法. 讨论了4株多抗对SMZ的检测灵敏度和对17种磺胺类药物(SAs)的相对亲和力趋势, 从药物分子二维结构上探讨了多抗对小分子抗原的识别能力. 结果表明, 3号多抗对SMZ的灵敏度最高, 但是4株多抗对17种SAs的相对亲和力趋势相似, 说明抗体对抗原的结合力大小与抗原的化学结构有关.  相似文献   
98.
Several new sulfonates and sulfonamides were synthesized with sulfonyl imidazoles as reagents. These compounds were characterized by ^1H NMR. The melting points of all solids synthesized were obtained on Fisher-Johns Melting Point Apparatus.  相似文献   
99.
A complete study of the asymmetric addition of phenylacetylene to ketones catalyzed by Schiff-base amino alcohol-Zn complex is reported in this article. The Schiff-base amino alcohols were easily prepared from amino acids in three steps. When the amount of ligand was 1%(molar fraction), an e.e. value up to 94% was obtained. A series of practical chiral ligands were applied in the enantioselective addition of phenylacetylene to ketones without adding another stronger Lewis acid except zinc.  相似文献   
100.
This study evaluated the removal of multiple pollutants,i.e.,polybrominated diphenyl ethers(PBDEs),novel halogenated flame retardants(HFRs),sulfonamide antibiotics(SAs),and heavy metals(HMs),by a fullscale reversed A2/O process in a sewage treatment plant(STP) in Guangzhou,China.The reversed A2/O process demonstrated high removal efficiencies(REs) for total PBDEs(60.5% ± 4.3%),novel HFRs(98.4% ±2.8%) and HMs(70.1% ±1.2%),and a relatively low RE for SAs(25.0% ± 2.3%).BDE 209...  相似文献   
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