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71.
Yukiko Tsuchi Hirotaka Watanabe Masaki Kogawa Biao Zhou Hiroaki Tsuji Motoi Kawatsura 《Tetrahedron letters》2018,59(13):1264-1267
We accomplished the palladium-catalyzed double substitution of 2-haloallylic acetates with nitrogen nucleophiles. During the Pd2(dba)3/DPPE-catalyzed reaction of 2-fluoroallylic acetates with N-substituted-p-toluenesulfonamide, two equivalents of nitrogen nucleophiles were introduced to the allyl unit with a Z-selectivity through the carbon–fluorine bond cleavage. We further demonstrated the reaction of 2-chloroallylic acetates, and succeeded in obtaining the same doubly-substituted products in good yields with a high Z-selectivity. 相似文献
72.
Hideki Okamoto Kazumasa Itani Minoru Yamaji Hiroyuki Konishi Hiromi Ota 《Tetrahedron letters》2018,59(4):388-391
Fluorescence properties of phthalimide derivatives (1) incorporating sulfonamide and acetamide functionalities at the 3-position were investigated both in solution and in the solid states to reveal the effects of the amide functionalities on the fluorescence properties. In the solid state, sulfonamides 1a and 1b, respectively, gave off red (λFmax 595?nm) and green (λFmax 537?nm) emission through an ESIPT process. Acetamides 1c and 1d, respectively displayed blue (λFmax 432?nm) and yellow (λFmax 560?nm) emission. Through simply modifying the amide functionality, phthalimide 1 displayed multicolor RGBY emission in the solid state. 相似文献
73.
74.
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
75.
《Journal of Coordination Chemistry》2012,65(16):2709-2718
Reaction of the N-tosyl-1,2-diaminopropane or N-tosyl-1,2-diaminobenzene with salicylaldehyde forms two new asymmetric sulfonamide Schiff bases, N-[2-(2-hydroxybenzylideneamino)propyl]-4-methylbenzenesulfonamide (H2L1 ) and N-[2-(2-hydroxybenzylideneamino)phenyl]-4-methylbenzenesulfonamide (H2L2 ). Two new complexes [CuL x (H2O)] (x = 1 for 1, x = 2 for 2) constructed from H2L x have been prepared and characterized via X-ray single-crystal diffraction, elemental analysis, FT-IR, UV-Vis, TGA, quantum chemical calculations, and photoluminescence measurements. Weak C–H ··· π, hydrogen bonds, π–π, and Cu ··· O weak interactions lead to 3-D supramolecular architecture, 1, and 1-D double chain, 2. 相似文献
76.
Patrick G. McGarraugh 《Tetrahedron》2009,65(2):449-1459
A new bifunctional organocatalyst with a novel structural and functional motif has been developed. This bifunctional sulfonamide organocatalyst was used in the conjugate addition of 1,3-dicarbonyl compounds (13) to β-nitrostyrenes (12). Yields up to 91% and enantiomeric excesses up to 79% were obtained in this reaction. This catalyst activates both 13 via its basic moiety and 12 through hydrogen bonding. 相似文献
77.
A copper triflate/t-BuOOAc-catalyzed amidation of allylic and benzylic acetates has been developed which is suitable for the coupling of a wide variety of functionalized sulfonamide nucleophiles with acetate electrophiles. The methodology allows for the amidation of benzylic substrates which are not further activated by an additional adjacent alkene or alkyne, enabling simple allylic acetates and primary benzylic acetates to be used as reaction partners. 相似文献
78.
合成了一系列结构全新的嘌呤磺胺类衍生物, 并应用溴化噻唑蓝四氮唑(MTT)法进行了初步体外抗肿瘤细胞增殖活性研究. 结果表明, 嘌呤环C2位、 N6位和N9位的取代对活性均有较大影响, C2位引入苯磺酰基哌嗪片段后有利于提高抗肿瘤活性. 化合物17d对3株肿瘤细胞PC-3, HCT116和K562 的增殖均有明显抑制作用, 且强度与阳性对照药Roscovitine相近. 相似文献
79.
80.
Dr. Debasis Banerjee Dr. Kathrin Junge Prof. Dr. Matthias Beller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(6):1656-1661
Transition‐metal‐catalyzed hydroamination reactions are sustainable and atom‐economical C N bond‐forming processes. Although remarkable progress has been made in the inter‐ and intramolecular amination of olefins and 1,3‐dienes, related intermolecular reactions of amides are still much less known. Control of the regioselectivity without analogous telomerization is the particular challenge in the catalytic hydroamidation of alkenes and 1,3‐dienes. Herein, we report a general protocol for the hydroamidation of electron‐deficient N‐heterocyclic amides and sulfonamides with 1,3‐dienes and vinyl pyridines in the presence of a catalyst derived from [{Pd(π‐cinnamyl)Cl}2] and ligand L7 or L10 . The reactions proceeded in good to excellent yield with high regioselectivity. The practical utility of our method is demonstrated by the hydroamidation of functionalized biologically active substrates. The high regioselectivity for linear amide products makes the procedure useful for the synthesis of a variety of allylic amides. 相似文献