Cu-catalyzed aerobic oxidative synthesis of sulfonamides from sulfonyl hydrazides and amines

An environmentally friendly route for sulfonamides has been developed. The oxidative coupling of sulfonyl hydrazides and amines was catalyzed by CuBr₂ to produce various sulfonamides with the water and nitrogen gas as byproducts. Preliminary experiments revealed that the sulfonyl radical is likely to be involved in the reaction mechanism.     

One-pot synthesis of sulfonamides from methyl sulfinates using ultrasound

Room temperature ultrasonic irradiation of neat mixtures of methyl sulfinates and primary or secondary amines (1.5 equiv) produced sulfinamides, which on m-CPBA oxidation (in dichloromethane) were converted into the corresponding sulfonamides. The two steps can be accomplished in one pot, in good overall yields, when using secondary amines, but primary amines give better sulfonamide yields when the peracid oxidation is effected on the purified sulfinamide. This constitutes a mild, efficient, and potentially scalable route to sulfonamides, which obviates the use of water sensitive, often lachrymatory sulfonyl chlorides and large reagent excesses.     

One‐Pot Synthesis of Sulfonamides and Sulfonyl Azides from Thiols using Chloramine‐T

A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols was accomplished by oxidation with chloramine‐T (=N‐chlorotosylamide=N‐chloro‐4‐methylbenzenesulfonamide), tetrabutylammonium chloride (Bu₄NCl), and H₂O. The sulfonyl chlorides were then further allowed to react with excess amine or NaN₃ in the same pot.     

Catalyzed hydroboration of allyl sulfonamides

The hydroboration of allyl sulfonamides (4-H₃CC₆H₄SO₂NRCH₂CH=CH₂: R=H, 1; Ph, 2; Bz, 3) with catecholborane (HBcat) using different rhodium catalysts has been examined using multinuclear NMR spectroscopy. Reactions give complex product distributions, regardless of the choice of catalyst, arising from a competing isomerization reaction. This isomerization reaction can be used with N-substituted allyl sulfonamides 2 and 3 to give the corresponding enamines (4-H₃CC₆H₄SO₂CH=CH₂CH₃), which in turn react with HBcat to give regioselective formation of one isomer (4-H₃CC₆H₄SO₂NRCH₂CH₂(Bcat)CH₃).     

A novel approach for the synthesis of alkyl and aryl sulfonamides

A novel approach for the synthesis of alkyl and aryl sulfonamides by the reaction of sulfonic acids, isocyanides and water in dichloromethane is reported at ambient temperature in excellent yields within 20 min. To the best of our knowledge this is the first report on the synthesis of this biologically important family using easily available sulfonic acids and isocyanides.     

Polypyrrole/silica/magnetite nanoparticles as a sorbent for the extraction of sulfonamides from water samples

A magnetic solid‐phase extraction sorbent of polypyrrole/silica/magnetite nanoparticles was successfully synthesized and applied for the extraction and preconcentration of sulfonamides in water samples. The magnetite nanoparticles provided a simple and fast separation method for the analytes in water samples. The silica coating increased the surface area that helped to increase the polypyrrole layer. The polypyrrole‐coated silica provided a high extraction efficiency due to the π–π and hydrophobic interactions between the polypyrrole and sulfonamides. Several parameters that affected the extraction efficiencies, i.e. the amount of sorbent, pH of the sample, extraction time, extraction temperature, ionic strength, and desorption conditions were investigated. Under the optimal conditions, the method was linear over the range of 0.30–200 μg/L for sulfadiazine and sulfamerazine, and 1.0–200 μg/L for sulfamethazine and sulfamonomethoxine. The limit of detection was 0.30 μg/L for sulfadiazine and sulfamerazine and 1.0 μg/L for sulfamethazine and sulfamonomethoxine. This simple and rapid method was successfully applied to efficiently extract sulfonamides from water samples. It showed a high extraction efficiency for all tested sulfonamides, and the recoveries were in the range of 86.7–99.7% with relative standard deviations of < 6%.     

Selective cleavage of the N-propargyl group from sulfonamides and amides under ruthenium catalysis

The selective cleavage of the N-propargyl group from sulfonamides and amides under ruthenium catalysis is described. The reaction tolerates a broad range of functional groups, and the desired products were obtained in 10–95% yield.     

Separation of sulfonamides by capillary electrochromatography

Summary The dual separation mechanism exhibited by capillary electrochromatography is demonstrated by the simultaneous separation of sulfonamides as charged and neutral species over a pH range of 2.5 to 6.9. The neutral sulfonamides were separated according to the difference in their hydrophobicities while charged components were separated by the differences in their electrophoretic mobilities. The limitation of capillary electrochromatography for acidic components was also examined.     

AgOTf catalyzed direct amination of benzyl alcohols with sulfonamides

AgOTf catalyzed direct amination of primary alcohols with sulfonamides is described. This effective catalyst requires no preactivation of the hydroxy group of alcohols and the reaction is environmentally benign with water as a by-product. Various primary alcohols on amination with sulfonamides gave the corresponding products in moderate to good yields.     

A simple and efficient method for sulfonylation of amines, alcohols and phenols with cupric oxide under mild conditions

Cupric Oxide efficiently catalyzed the synthesis of sulfonamides and sulfonic esters. This method has been applied to a variety of substrates including nucleophilic and sterically-hindered amines, alcohols and phenols with excellent yields of sulfonamides and sulfonic esters. The remarkable selectivity under mild and neutral conditions of this commercially available inexpensive catalyst is an attractive feature of this method.     

Rhodium-catalyzed aerobic N-alkylation of sulfonamides with alcohols

By using the famous Wilkinson’s catalyst,N-alkylation of sulfonamides can be easily realized under mild aerobic conditions by using alcohols as the alkylating reagent,giving monoalkylated sulfonamides in high yields and selectivities with water produced as the only byproduct.This advantageous aerobic method is potentially general in substrate scope that it can also be applied to other amides,amines and alcohols.     

Fluoroquinolones and sulfonamides: features of their determination in water. A review

Sulfonamides and fluoroquinolones are two group of antibiotics widely used in the treatment of bacterial infections. Monitoring these residues in live animals and animal products is commonly legislated; however, the environmental occurrence and fate is still sporadically assessed. The development of adequate analytical methods is a key issue to provide accurate data on concentrations of antimicrobial compounds and their residues in different organic matters. This review presents an overview of proposed methods published between 2008 and 2013 for analysis of fluoroquinolones and sulfonamides with special emphasis on sample preparation and detection systems employed. The coupling of high-performance liquid chromatography and mass spectrometry has been the most widely used method to determination of sulfonamides and fluoroquinolones, concomitantly to other antibiotics residues, due to high sensitivity and selectivity. The main drawbacks of this technique are the high cost and the equipment complexity. The coupling high-performance liquid chromatography and fluorescence detection has also been used to fluoroquinolones determination. Their fluorescent properties allowed the development of several methods with limits of detection in ng L^?1 range. Sample preparation is an important tool to reach lower detection limits and the online solid-phase extraction has a broader use. The hydrophilic–lipophilic balance polymeric are the mostly applied sorbents for sulfonamides and fluoroquinolones preconcentration. These sorbents have allowed reaching better recoveries and sensitivity improvement. Physico-chemical properties of these antibiotic groups in addition to trends on papers occurrence and frequency of analysis in different types of water (surface water, groundwater, drinking water and wastewater) are discussed.     

Determination and removal of sulfonamides and quinolones from environmental water samples using magnetic adsorbents

In this study, the magnetic materials known as polymerized ionic liquid@3‐(trimethoxysilyl)propyl methacrylate@Fe₃O₄ nanoparticles were synthesized and utilized as potential adsorbents. First, these nanoparticles were applied to the analysis of sulfonamides and quinolones present in different water samples using magnetic solid phase extraction and high‐performance liquid chromatography. Under optimized conditions, the developed method showed excellent detection sensitivity, with limits of detection (S/N = 3) and quantification limits (S/N = 10) within 0.2–1.0 and 0.8–3.4 μg/L, respectively. The spiked recoveries of the SAs and QNs in environmental water samples ranged from 83.5 to 103.0%, with RSDs of less than 4.5%. In addition, the adsorbents effectively removed sulfamethoxazole and ofloxacin present in existing aquatic environments. The adsorption kinetics and isotherms of sulfamethoxazole and ofloxacin on the magnetic adsorbents were studied to assess removal performance. The results indicate that the adsorption process follows a pseudo‐second‐order mechanism, which reveals that the sorption mechanism is the rate‐limiting step and produces high q_max values (sulfamethoxazole = 70.35 mg/g and ofloxacin = 48.95 mg/g), thus demonstrating the enormous adsorption capacity of these magnetic adsorbents.     

A general and mild two-step procedure for the synthesis of aryl and heteroaryl sulfonamides from the corresponding iodides

A mild two-step preparation of aryl and heteroaryl sulfonyl chlorides and sulfonamides from their corresponding iodides is developed. Acid labile functionalities are shown to be stable under both the copper-catalysed coupling and the subsequent oxidative chlorination.     

Copper-catalyzed denitrogenative N-arylation of sulfoximines and sulfonamides with arylhydrazines

A Cu-mediated ligand-free arylation of NH-sulfoximines and sulfonamides by arylhydrazine hydrochlorides was herein demonstrated. The oxidative transformation provided an easy access towards N-aryl sulfoximines and sulfonamides in high yields (up to 93% yields) with broad functional groups tolerance (up to 36 examples). The protocol was proposed to take place through the free radical pathway based on the results of control reactions and EPR analysis.     

毛细管电泳-电化学检测法测定饲料中的磺胺类药物

采用毛细管电泳-电化学检测法(CE-ED),对饲料中的6种磺胺类药物磺胺脒、磺胺二甲嘧啶、磺胺甲嘧啶、磺胺二甲氧嘧啶、磺胺嘧啶、磺胺甲恶唑进行了分离和测定。分别考察了工作电极电位、运行缓冲液的pH和浓度、分离电压和进样时间等实验参数对实验结果的影响。在优化的实验条件下,以直径300μm的碳圆盘电极为工作电极,检测电位为0.95 V(vs.SCE),在30 mmol/L硼砂-KH2PO4(pH7.6)的运行缓冲溶液中,6个分析物能够在16 min内实现很好的基线分离,被测物浓度与峰电流在3个数量级呈良好的线性,检出限(S/N=3)范围0.08～0.20μg/mL。该方法已应用于实际样品的分析。     

Simple and rapid determination of sulfonamides in milk using Ether-type column liquid chromatography

A simplified and rapid determining/identifying method for residual sulfonamides (SAs) in milk by using Ether-type stationary phase, which made in our lab, was presented. The target analytes were extracted by mixing with ethanol-acetic acid (97:3, v/v) followed by centrifugation. The procedure used a Ether-type C8 column, isocratic elution with acetonitrile-water (5:95, v/v), and a photo-diode array detector. The linear range of determination was 50-10,000 μg/L for sulfanilamide and 100-10,000 μg/L for sulfadiazine, sulfamerazine, sulfamethazine. Average recoveries of four SAs (spiked 0.5, 1.0 and 1.5 μg/mL) ranged from 80.1% to 87.6%, with relative standard deviations between 3.4% and 5.8%. The total time and solvent required for the analysis of one sample were <15 min and <1.0 mL of ethanol and 0.6 mL of acetonitrile, respectively. The developed procedure was nearly harmless to the human and environment.     

Synthesis of novel cyclopropylic sulfones and sulfonamides acting as glucokinase activators

A synthetic route towards cyclopropylic compounds, which act as glucokinase activators is described herein. The present synthesis gives easy and rapid access to a wide variety of either sulfones or sulfonamides starting from readily available late-stage intermediates.     

Rapid simultaneous determination of 14 sulfonamides in wastewater by liquid chromatography tandem mass spectrometry

This paper describes a rapid method for the determination of 14 kinds of sulfonamides (SAs) in wastewater using SPE, and LC-MS/MS with positive ESI (ESI(+)) and selected reaction monitoring (SRM) mode. The SPE was performed on an Oasis hydrophilic-lipophilic-balanced (HLB) cartridge. Chromatographic separation on a C18 column was achieved using a binary eluent containing methanol and water with 0.2% formic acid. Typical recoveries of the analytes ranged from 22.3 to 87.0% at a fortification level of 100 ng/L. The LODs in wastewater except sulfathiazole (3 ng/L) could be detected and quantified at levels as low as 1 ng/L. Finally, the method was applied to water from the municipal outlet and the aquaculture wastewater effluent. Sulfamethazine (SM(2)), sulfamethoxypyridazine (SMP), and sulfamethoxazole (SMZ) were most frequently found in wastewater in a concentration range between 1.2 and 31.7 ng/L.     

Potassium tert-butoxide-mediated metal-free synthesis of sulfonamides from sodium sulfinates and N,N-disubstituted formamides

By using formamides as amine sources, a novel and efficient KO-t-Bu mediated amination of sodium sulfinates has been developed. The reaction utilizes readily available starting materials under metal-free conditions, thus providing an alternative and attractive route to sulfonamides.