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N-Alkylation of sulfonamides using cyclic ethers as alkylation reagents and Brønsted acid as a catalyst produced pyrrolidine and piperidine derivatives in good yields. When using symmetrical and unsymmetrical ethers as alkylation reagents, mono-N-alkylation of sulfonamides took place to afford the corresponding products. 相似文献
54.
《Arabian Journal of Chemistry》2020,13(1):1271-1282
A series of novel naphtho[1,2-e][1,3]oxazines bearing arylsulfonamide moiety have been synthesized via a one-pot approach and in a green reaction medium. These new naphtho[1,2-e][1,3]oxazine derivatives have been characterized by their 1H NMR, 13C NMR and the X-ray single crystallography method for compound 7a. All the newly synthesized compounds were examined for their in vitro anticancer activity against breast (MCF-7), colon (HCT116), and B-CLL (Waco3-CD5) cancers. Some of these compounds such as 7j and 7l showed remarkable activities against MCF-7 (breast) and HCT116 (colon) cancers with comparable IC50 (The half maximal inhibitory concentration) values as that of known drugs such as 5-fluorouracil (5-FU). In vitro antimicrobial activities of all compounds were also evaluated against five human pathogenic fungi strains and two bacteria (one gram positive and one gram negative). The best MICs (Minimum Inhibitory Concentrations) were found against the C. albicans. 相似文献
55.
α-Arylation of methanesulfonamides using palladium catalysis is described. For example, treatment of N-benzyl-N-methylmethanesulfonamide with catalytic Pd(OAc)2 in the presence of sodium tert-butoxide, triphenylphosphine and toluene afforded N-benzyl-N-methylphenylmethanesulfonamide in 66% yield. 相似文献
56.
Xiaolei Huang Yan Wang Jingbo Lan Jingsong You 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(32):9536-9540
Disclosed herein is a RhIII‐catalyzed chelation‐assisted activation of unreactive C H bonds, thus enabling an intermolecular amidation to provide a practical and step‐economic route to 2‐(pyridin‐2‐yl)ethanamine derivatives. Substrates with other N‐donor groups are also compatible with the amidation. This protocol proceeds at room temperature, has a relatively broad functional‐group tolerance and high selectivity, and demonstrates the potential of rhodium(III) in the promotive functionalization of unreactive C H bonds. A rhodacycle having a SbF6− counterion was identified as a plausible intermediate. 相似文献
57.
超高效液相色谱-串联质谱法同时测定水和沉积物中磺胺类、喹诺酮类和氯霉素类抗生素残留 总被引:1,自引:0,他引:1
建立了超高效液相色谱-串联质谱法(UPLC-MS/MS)同时测定水及沉积物中磺胺类、喹诺酮类和氯霉素类抗生素残留。水样前处理采用固相萃取,沉积物样品前处理采用加速溶剂萃取。该方法在9min内可完成目标化合物的UPLC-MS/MS分离分析。对于水和沉积物,20种目标化合物的检出限(S/N≥3)分别介于0.01~0.50ng/L和0.005~0.2μg/kg之间,在各自考察的浓度范围内线性关系良好(r≥0.995)。采用该方法测定了苏州地区地表水,共检出10种抗生素,浓度范围为0.79~240ng/L;测定底泥样品,共检出11种抗生素,浓度范围为0.37~27.0μg/kg。 相似文献
58.
A novel 5-((4-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-ylsulfonyl)phenylamino)methyl)quinolin-8-ol(HTPSMQol) was synthesized by optimized reaction of 4-(6,7-dihydrothieno[3,2-c]pyridin-5(4H)-ylsulfonyl)aniline with 5-chloromethyl-8-hydroxy-quinoline hydrochloride(CMHQ).Also complexes of HTPSMQol were prepared by using various M(Ⅱ) metal salts.All compounds were analyzed by spectroscopic techniques and screened against various strains of microorganisms.The results showed higher antimicrobial activity of HTPSMQol compared to its metal complexes and comparable with Ciprofloxacin. 相似文献
59.
Nani Babu PalakurthyBhubaneswar Mandal 《Tetrahedron letters》2011,52(52):7132-7134
The N-hydroxybenzotriazole (HOBt) sulfonate esters undergo amidation under ambient conditions in the presence of di-isopropylethyl amine. This method can be applied to varieties of amines including sterically hindered amino acid esters in less time with reasonably good yields.HOBt ester of sulfonic acids can be a replacement for pentafluorophenyl and trichlorophenyl ester as well as chloride moiety of sulfonyl chloride for amidation. 相似文献
60.
液相色谱串联质谱法测定猪肉和猪肝中9种磺胺类药物的残留 总被引:1,自引:0,他引:1
建立了高效液相色谱-串联质谱法(HPLC/MS/MS)同时测定猪肉及猪肝中9种磺胺类药物残留的检测方法.样品经10%的Na2SO4溶液和乙腈-氯仿(10:1)提取,乙腈饱和正己烷去脂,使用乙二胺-N-丙基硅烷(PSA)和十八烷基键合相硅胶(ODS C18-N)两种基质分散净化剂净化,采用LC-MS/MS多反应监测(MRM)正离子模式测定,内标法定量.9种磺胺检出限为0.1 ~0.8 μg/kg,在5,10,20μg/kg 3个浓度添加水平,回收率为74.1% ~ 115.8%,相对标准偏差均小于6.2%(n=6). 相似文献