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201.
Christina Strauch Dr. Sebastian Schroeder Dr. Gwendal Grelier Prof. Dr. Meike Niggemann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(53):e202201830
Vinyl triflimides are a new compound class with unknown reactivity. A computational analysis identified homolytic cleavage of the N−Tf bond induced by triplet–triplet energy transfer (EnT) as a highly interesting reaction type that might be accessible. A combination of experimental and mechanistic work verified this hypothesis and proved the generated radicals to be amenable to radical–radical coupling. Thereby, vinyl triflimides were transformed into a range of α-quaternary, β-trifluoromethylated amines in a 1,2-difunctionalization reaction with no need for external CF3 reagents. 相似文献
202.
Zhen Gong Qianqian Wan Jiayi Song Meng Li Wenting He Zixin Zhou Ping Su Chunting Zhang Yi Yang 《Journal of separation science》2022,45(9):1514-1524
A magnetic solid phase extraction method based on magnetic covalent organic frameworks (TpBD@Fe3O4; 2,4,6-triformylphloroglucinol (Tp) and benzidine (BD)) combined with high performance liquid chromatography has been developed to detect the sulfonamides including sulfadiazine, sulfamerazine, sulfamethazine, and sulfamethoxazole in milk and meat. TpBD@Fe3O4 were synthesized at room temperature under mild reaction conditions with a simple and rapid operation. The TpBD@Fe3O4 exhibited higher extraction efficiency because of the π–π and electrostatic interactions between the benzene ring structure of the TpBD and the sulfonamide molecules. The extraction conditions including the dosage of adsorbents, the type and dosage of eluent, the elution time, and the pH of the sample solution were fully optimized. The detection results showed good linearity over a wide range (50–5 × 104 ng/mL) and low detection limits (3.39–5.77 ng/mL) for the sulfonamide targets. The practicability of this magnetic solidphase extraction-high-performance liquid chromatography method was further evaluated by analyzing milk and meat samples, with recoveries of the targets of 71.6–110.8% in milk and 71.9–109.7% in pork. The successful detection of sulfonamides residues has demonstrated the TpBD@Fe3O4 excellent practical potential for analyzing pharmaceutical residues in animal-derived foods. 相似文献
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Taichi Kano Dr. Yukako Yamaguchi Keiji Maruoka Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(27):6678-6687
Amino sulfonamide catalyst : A distal proton of the axially chiral amino sulfonamide (S)‐ 1 realized the opposite diastereoselectivity in Mannich and cross‐aldol reactions compared with that observed in proline‐catalyzed reactions. The reactions catalyzed by (S)‐ 1 proceeded smoothly to give the anti‐Mannich and syn‐aldol adducts in excellent enantioselectivity (see scheme).
205.
建立了高效液相色谱-二极管阵列检测法同时测定兽药粉剂中11种磺胺类药物的分析方法。试样采用95%乙腈提取,经碱性氧化铝固相萃取小柱净化,15%乙腈复溶残渣后用Agilent TC-C18色谱柱分离,0.017 mol/L磷酸溶液和乙腈为流动相进行梯度洗脱,二极管阵列检测器进行检测。结果表明,在优化实验条件下,11种磺胺类药物的色谱分离和相应光谱图匹配理想;在0.25~10.0 mg/L范围内线性关系良好;兽药粉剂中添加0.5~5.0 mg/kg水平的11种磺胺类药物的回收率在67%~97%之间,相对标准偏差为1.5%~9.9%;以3倍信噪比(S/N=3)结合相应光谱图计算得11种磺胺类药物的检出限均为0.25 mg/kg。 相似文献
206.
Dean Marković Dr. Chandra M. R. Volla Dr. Pierre Vogel Prof. Dr. Adrián Varela‐Álvarez José A. Sordo Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(20):5969-5975
The first ene reactions of SO2 and unfunctionalized alkenes are reported. Calculations suggest that the endergonic ene reactions of SO2 with alkenes can be used to generate β,γ‐unsaturated sulfinyl and sulfonyl compounds. Indeed, in the presence of one equivalent of BCl3, the unstable sulfinic acid form stable sulfinic acid?BCl3 complexes that can be reacted in situ with NCS to generate corresponding sulfonyl chlorides, or with a base to generate corresponding sulfinates. The latter can be reacted with electrophiles to generate sulfones, or with silyl chloride to form β,γ‐unsaturated silyl sulfinates. The sulfinic acid?BCl3 complexes can be reacted with ethers that act as oxygen nucleophiles to produce corresponding sulfinic esters. Thus one‐pot, three‐component synthesis of β,γ‐unsaturated sulfonamides, sulfinyl esters and sulfones have been developed starting from alkenes and sulfur dioxide (reagent and solvent). 相似文献
207.
A full account of the oxidative dearomatization of para- and ortho-phenolic sulfonamides is provided together with an overview of the chemistry of the products and their elaboration to building blocks for spirocyclic alkaloids. A concise total synthesis of putative lepadiformine complements the discussion. 相似文献
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The elimination of benzotriazolyl group from N-(α-benzotriazol-1-ylalkyl)amides and N-(α-benzotriazol-1-ylalkyl)sulfonamides are readily realized with samarium diiodide as a reducing agent. The resulting intermediates undergo a dimerization or cross-coupling reaction with carbonyl compounds, thus affording the corresponding dimers or α-hydroxyalkylated sulfonamides in moderate yields. 相似文献