Synthesis of sulfonamide and their synthetic and therapeutic applications: Recent advances

Oxidative N-functionalization of primary sulfonamides with aliphatic aldehydes: a green synthesis of α-sulfonamido acetals

A straightforward and scalable method for direct C-N bond formation is developed using primary sulfonamides and aliphatic aldehydes. The reaction proceeds efficiently within a catalytic system that comprises 0.3 equivalents of sodium iodide and 1.2 equivalents of sodium percarbonate, facilitating rapid synthesis of α-sulfonamido acetals with excellent functional group tolerance. This protocol demonstrates significant potential for medicinal chemistry applications, particularly in the derivatization of sulfa drugs into α-amino alcohols/esters.

Design, synthesis, biological evaluation, and computational insights of 2-(Aryl)benzo[d]imidazo[2,1-b]thiazole-7-sulfonamide derivatives as potent antitubercular and antibacterial agents

A series of 2-(aryl)benzo[d]imidazo[2,1-b]thiazole-7-sulfonamide derivatives were synthesized and evaluated for their antitubercular and antibacterial activities, molecular docking, and DFT studies. The compounds were synthesized through a multi-step reactions, with yields varying based on the electronic and steric effects of the substituents. Among the derivatives, 5b, 5d, and 5h exhibited potent antitubercular activity against Mycobacterium tuberculosis (H37Rv strain) with minimum inhibitory concentrations (MICs) of 1.6 µg/mL, comparable to some standard drugs like isoniazid. Antibacterial testing revealed that 2-(2,4-dichlorophenyl)benzo[d]imidazo[2,1-b]thiazole-7-sulfonamide displayed significant activity against Gram-positive bacteria, with MICs as low as 6.25 µg/mL for Staphylococcus aureus and Bacillus subtilis. The molecular docking and DFT analyses provided insights into the binding interactions and electronic structures of these compounds, with halogen substitutions enhancing biological activity due to increased electron-withdrawing effects. MESP studies showed a distinct electron density distribution, supporting the observed bioactivity. For antitubercular activity, compounds 5b, 5d, and 5h demonstrated potent binding affinities (-6.2 to -5.9 kcal/mol) against the DprE1 enzyme. Compound 5f showed remarkable antibacterial efficacy, with a docking score of -7.9 kcal/mol against 2,2-dialkylglycine decarboxylase The DFT analysis revealed that 5a, with a methoxy substituent, had the highest reactivity (ΔE = 3.86 eV), while halogenated derivatives, such as 5f, exhibited increased chemical stability (ΔE = 4.24 eV). ADME studies showed that 5f having favorable lipophilicity and enzyme inhibition. These findings suggested that these derivatives could serve as potential candidates for further drug development against bacterial and mycobacterial infections.

Construction of Biaryl Sulfonamides via Pd(II)-Catalyzed Cross-Coupling of C(sp2)-H Bonds with Iodobenzenesulfonamides

This study describes the utility of Pd(II)-catalyzed C-H arylation of benzamides for constructing biaryl sulfonamides. Sulfonamides are known for their promising applications in pharmaceuticals and agrochemicals. A literature review revealed that biaryl sulfonamides were generally constructed via the traditional cross-coupling reactions. We report a progressive method for obtaining biaryl sulfonamides via the Pd(II)-catalyzed bidentate directing group (8-aminoquinoline or picolinamide)-assisted cross-coupling of sp2 C-H bonds of aromatic carboxamides with iodobenzenesulfonamides. After the C-H arylation reactions, we attempted the removal of the 8-aminoquinoline from the synthesized biaryl scaffolds possessing the carboxamide and sulfonamide moieties using triflic acid. In some cases, we observed the occurrence of decarboxylation and Friedel-Crafts acylation, affording interesting aromatic scaffolds possessing the sulfonamide moiety. The current work contributes toward developing alternative ways for assembling various biaryl sulfonamides.

Enhanced Antimicrobial Efficacy of Sulfones and Sulfonamides via Cage-Like Silsesquioxane Incorporation

This work introduces a novel class of hybrid antimicrobial agents by integrating sulfone and sulfonamide functionalities with polyhedral oligomeric silsesquioxanes (POSSs). By employing efficient synthetic protocols, we have successfully prepared both sulfone (ethylvinylsulfone-POSS and phenylethylsulfone-POSS) and sulfonamide (benzenesulfonamide-POSS, p-toluenesulfonamide-POSS, 3-fluorobenzenesulfonamide-POSS, and 2-naphthalenesulfonamide-POSS) derivatives with high yields (73-90%). All derivatives were examined using Fourier transform infrared spectroscopy, multinuclear (1H, 13C, 19F, and 29Si) NMR spectroscopy, MALDI-ToF MS spectrometry, and elemental analysis. Additionally, the crystal structure of the p-toluenesulfonamide-POSS hybrid was revealed. The unique cage-like POSS structure not only imparts enhanced thermal and chemical stability, a common feature of silsesquioxane-based hybrids, but also boosts the lipophilic character of these compounds, thereby facilitating their interaction with microbial membranes. This interaction, likely resulting in membrane disruption and cell lysis, translates into potent antimicrobial activity (against Escherichia coli, Pseudomonas aeruginosa, Enterococcus hirae, Staphylococcus aureus, and Candida albicans)─especially against Gram-positive bacteria─at remarkably low minimum inhibitory concentrations in the range from 125 to 3000 μM. In turn, E. hirae and S. aureus were more susceptible compared to Gram-negative bacteria and C. albicans. The strategic incorporation of POSSs into these sulfur-based moieties represents a significant breakthrough, opening new avenues for the development of advanced antimicrobial coatings and therapeutic agents in the fight against antibiotic resistance.

Ultramicroporous Ionic Liquid-Supported Aerogel Composites

Recently, low-concentration ammonia (NH3) capture has attracted considerable attention for applications in ammonia-hydrogen fuel cells and confined spaces. The main objective of this study was to develop novel ultramicropore ionic liquid-supported aerogel composites (UILACs), designed to effectively expose the multiple hydrogen bonding sites of the ionic liquid through the constructed ultramicropore structure in order to capture and selectively separate low-concentration NH3. UILACs achieved a maximum NH3 capacity of 164.69 mg NH3/g absorbent at 25 °C and 0.10 MPa, which was 3.47 times higher than that of the pure aerogel. In breakthrough experiments with low NH3 concentrations (1000-10,000 ppm), UILACs exhibited exceptional NH3/H2 and NH3/N2 selectivity of 2460 and 10,474, respectively, at 1000 ppm NH3, values which are 31.5 and 22.1 times higher than the pure aerogel. These values significantly exceeded those of aerogels, owing to high hydroxyl ammonium ionic liquid (HAIL) loading, interactions between HAIL and NH3, and ultramicropores, as confirmed by density functional theory (DFT) calculations and isothermal analysis. Furthermore, UILACs maintained stable adsorption performance through ten adsorption-desorption cycles, demonstrating UILACs' potentials for efficient NH3 capture and separation in energy applications.

Bridged Bicyclic γ-Sultams by Intramolecular Flow Photochemical [2 + 2] Cycloaddition

An elegant synthetic approach to the construction of a novel saturated heterocycle─2-thia-3-azabicyclo[2.1.1]hexane 2,2-dioxide─was designed. The key step included intramolecular flow photochemical [2 + 2] cycloaddition of appropriately substituted dienes, which were in turn obtained from readily available starting materials on a multigram scale. Further synthetic transformations of the resulting bicyclic compounds enabled the preparation of numerous functionalized derivatives useful for early drug discovery programs as promising isosteres of pyrrolidine, pyrrolidone, and γ-sultams. These studies also demonstrated the tolerance of the title bicyclic system to typical organic chemistry reaction conditions.

Catalytic Atroposelective Electrophilic Amination to Access Axially Chiral Diaryl Phenols

An enantioselective synthesis of axially chiral diaryl phenols containing sulfonamide groups has been achieved involving an electrophilic amination of 1,1'-biaryl-2,6-diols with N-sulfonyl quinone diimines, catalyzed by a chiral phosphoric acid. This atroposelective reaction offers a modular approach to enantiopure diaryl phenols, with good-to-excellent yields.

A decade of research effort in synthesis, biological activity assessments, and mechanistic investigations of sulfamethazine-incorporating molecules

Because of its importance in medicinal chemistry, scientific researchers have been interested in incorporating sulfamethazine in developing biologically active candidates. To achieve this, several synthetic approaches have been adopted. The adopted approaches included condensation with electrophilic reactants, coupling with nucleophilic aromatics and active methylene compounds, Knoevenagel condensation, Doebner Miller reaction, microwave-assisted click cycloaddition, green reaction routes, and multicomponent reaction. Linking this molecular scaffold to a variety of heterocycles in the last 10 years furnished a set of potential anti-inflammatory, antiviral, anticancer, antiparkinsonian, neuroprotective, and antidiabetic candidates targeting H5N1 NA, epidermal growth factor receptor, acetylcholinesterase (AChE), butylcholinesterase (BChE), human carbonic anhydrase (hCA), α-amylase, and α-glucosidase. This review reports all the adopted synthetic approaches, the biological activities studied, structure-activity relationship analyses, and the mechanistic investigations of the reported organic sulfamethazine-incorporating molecules throughout 2015-2024, based on information retrieved from three search engines: Scopus, PubMed, and Google Scholar.

Multi-organelle imaging with dye combinations: targeting the ER, mitochondria, and plasma membrane

Multi-organelle imaging allows the visualization of multiple organelles within a single cell, allowing monitoring of the cellular processes in real-time using various fluorescent probes that target specific organelles. However, the limited availability of fluorophores and potential spectral overlap present challenges, and many optimized designs are still in nascency. In this work, we synthesized various sulfonamide-based organic fluorophores that emit in the blue, green, and red regions to target different sub-cellular organelles. By utilizing binary mixtures, we successfully demonstrated multiple imaging of the sub-cellular organelles, such as the endoplasmic reticulum, plasma membrane, and mitochondria in HeLa cells, and dual imaging of the endoplasmic reticulum and mitochondria in A549 lung carcinoma cells with the help of blue and red-emitting fluorophores without any spectral spillover. Additionally, these photostable probes allowed precise cell staining and differentiation, structural features, and live cell dynamics. This approach of utilizing fluorescent mixtures can gain traction for various cellular studies and investigations.

Silyl Triflate-Promoted Sulfonylations

Sulfonamides are prevalent functional groups represented in both natural and pharmaceutical products. The synthesis of sulfonamides is often straightforward when using nucleophilic amines and electrophilic sulfonyl chlorides. When reactivity challenges arise for nontraditional substrates, harsh conditions or new synthetic routes may be required. Here we report a method using silyl triflate additives to overcome reactivity limitations when electron deficient and sterically encumbered amines are used in conjunction with electron rich or bulky sulfonyl chlorides.

Synthesis of Sulfonamide-Based Schiff Bases as Potent Anticancer Agents: Spectral Analyses, Biological Activity, Molecular Docking, ADME, DFT, and Pharmacophore Modelling Studies

The current study focuses on the synthesis and characterization of six benzenesulfonamide-based Schiff base derivatives (7-12) with various electron-withdrawing and electron-donating substituents (-F, -CI, -Br, -CH3, and -OCH3) and the assessment of their antiproliferative activities against human lung (A549) and liver (HepG2) cancer cell lines using in vitro and in silico approaches. The structures of the synthesized compounds (7-12) were elucidated by elemental analysis and FT-IR, 1D (1H, 13C, APT, and DEPT-135), and 2D (HMQC and HMBC) NMR spectroscopies. The cytotoxic activities of the targeted compounds were determined at various concentrations against these cancer cell lines for 72 h, using the MTT method. The targeted molecules (7-12) demonstrated remarkable antiproliferative activities, with IC50 values ranging from 6.032-9.533 μM against the A549 cell line and 5.244-9.629 μM against the HepG2 cell line. These compounds showed activities at lower or very similar concentrations to cisplatin against the A549 cell line and at much lower concentrations than cisplatin against the HepG2 cell line. Among them, compounds 10 and 12 were found to be more effective against A549 and HepG2 cells, respectively, than cisplatin. These compounds were analyzed by interacting with the 1BNA, 4HJO, and 4ASD crystal structures in molecular docking studies. The docking score of 4ASD-compound 12 interaction was calculated as -4.045 kcal/mol, 4HJO-compound 10 interaction was calculated as -5.179 kcal/mol and 1BNA-compound 10 interaction was calculated as -8.571 kcal/mol and it was determined that these compounds were theoretically better than Cisplatin. In the present study, ADME data were estimated using the web tool SwissADME. With ADME, it was calculated that the logP value of compounds 7-12 was less than 5, the HBD number was 1, the HBA number was 7 or 8, and the molecular weight was less than 500. Properties such as the electrophilic index and chemical hardness of the designed compounds were examined by density functional theory (DFT) using B3LYP/6-311G**. In conclusion, these compounds have emerged as promising new anti-cancer drug candidates.

Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

The reactivity of our recently disclosed hypervalent iodine reagents (HIRs) bearing a benzylamine with in situ-generated sulfenate salts was investigated. Under the studied conditions sulfonamides have been obtained in up to 52% yield. This reaction has been extended to a variety of HIRs and sulfenate salts to explore the different reactivity of these new reagents. A plausible mechanism is proposed, suggesting a possible radical pathway.

Synthesis of benzosultams via Ag(I)-catalyzed alkylative cyclization of vinyl sulfonamides

A convenient method to access benzo-fused-γ-sultams via alkyl radical induced cyclization of vinyl sulfonamides is presented. A wide range of carboxylic acids including sterically hindered adamantanes participated as alkyl donors in this Ag(I)-catalyzed decarboxylative alkylation. The reaction utilizes readily available starting materials and demonstrates a broad substrate scope.

Palladium catalyzed C(sp3)-H alkylation of 8-methylquinolines with aziridines: access to functionalized γ-quinolinylpropylamines

Palladium-catalyzed directed site-selective C(sp3)-H alkylation of 8-methylquinolines has been accomplished using aziridine as the alkylating source via a sequential C-H and C-N bond activation process. The site selectivity, functional group tolerance and possible late-stage modifications are important practical features of this reaction.

New avenues of combating antibiotic resistance by targeting cryptic pockets

Antibiotic resistance is a global health concern that is rapidly spreading among human and animal pathogens. Developing novel antibiotics is one of the most significant approaches to surmount antibiotic resistance. Given the difficult in identifying novel targets, cryptic binding sites provide new pockets for compounds design to combat antibiotic resistance. However, there exists a lack of comprehensive analysis and discussion on the successful utilization of cryptic pockets in overcoming antibiotic resistance. Here, we systematically analyze the crucial role of cryptic pockets in neutralizing antibiotic resistance. First, antibiotic resistance development and associated resistance mechanisms are summarized. Then, the advantages and mechanisms of cryptic pockets for overcoming antibiotic resistance were discussed. Specific cryptic pockets in resistant proteins and successful case studies of designed inhibitors are exemplified. This review provides insight into the discovery of cryptic pockets for drug design as an approach to overcome antibiotic resistance.

Precise photothermal treatment of bacterial infection mediated by charge-switchable nanoplatform with acylsulfonamide betaine surface

Photothermal therapy (PTT) offers a promising approach for the treatment of drug-resistant bacterial-infected wounds, yet it requires precise targeting of thermal damage to bacteria rather than healthy tissues. Herein, ultrasmall CuS NPs modified with polyzwitterion containing acylsulfonamide betaine (PCBSA@CuS), which provides a sensitive and reversible charge conversion around pH 6.8, are used to enhance the healing of bacteria-infected wounds. In the acidic infection microenvironment, the majority of PCBSA@CuS can electrostatically adsorb onto bacterial cells through cationic exposure, resulting in direct damage and death of bacteria upon NIR irradiation. Additionally, the photothermal NPs rapidly return to a zwitterionic nature in normal physiological environments, ensuring lower affinity and avoiding thermal damage to healthy tissues during continuous PTT. Compared to inert photothermal systems such as PEG-modified CuS NPs, the NPs used in this study exhibited higher bactericidal and wound healing efficacy. Therefore, this nano-antibacterial agent with highly sensitive thermal-targeting function provides a novel photothermal strategy for efficient and biosafe treatment of infected wounds.

Based on magnetically recoverable catalysts: a green strategy to sulfonamides

The synthesis of sulfonamides, a class of compounds with significant pharmaceutical and medicinal applications, has seen remarkable advancements with the advent of magnetic nanocatalysts. Magnetic nanocomposites are one of the most efficient and widely used catalysts, and they are in complete harmony with the principles of modern green chemistry from the point of view of catalysis. These catalysts, typically composed of metal complexes supported on magnetic nanoparticles, offer unique advantages such as ease of recovery and reusability, which are crucial for sustainable and eco-friendly chemical processes. This review comprehensively examines recent developments in applying magnetic nanocatalysts to prepare sulfonamides. Key focus areas include the design and synthesis of various magnetic nanocatalysts (MNC), their catalytic performance in different reaction conditions, and mechanistic insights into their catalytic activity. By summarizing the latest research and technological advancements, this article aims to provide a valuable resource for researchers and practitioners in catalysis and pharmaceutical chemistry.

Development of novel organometallic sulfonamides with N-ethyl or N-methyl benzenesulfonamide units as potential human carbonic anhydrase I, II, IX and XII isoforms' inhibitors: Synthesis, biological evaluation and docking studies

In the search of new cymantrenyl- and ferrocenyl-sulfonamides as potencial inhibitors of human carbonic anhydrases (hCAs), four compounds based on N-ethyl or N-methyl benzenesulfonamide units have been obtained. These cymantrenyl (1a-b) and ferrocenyl (2a-b) derivatives were prepared by the reaction between aminobenzene sulfonamides ([NH2-(CH2)n-(C6H4)-SO2-NH2)], where n = 1, 2) with cymantrenyl sulfonyl chloride (P1) or ferrocenyl sulfonyl chloride (P2), respectively. All compounds were characterized by conventional spectroscopic techniques and cyclic voltammetry. In the solid state, the molecular structures of compounds 1a, 1b, and 2b were determined by single-crystal X-ray diffraction. Biological evaluation as carbonic anhydrases inhibitors were carried out and showed derivatives 1b y 2b present a higher inhibition than the drug control for the Human Carbonic Anhydrase (hCA) II and IX isoforms (KI = 7.3 nM and 5.8 nM, respectively) and behave as selective inhibition for hCA II isoform. Finally, the docking studies confirmed they share the same binding site and interactions as the known inhibitors acetazolamide (AAZ) and agree with biological studies.

Tail-approach based design, synthesis, and molecular modeling of benzenesulfonamides carrying thiadiazole and urea moieties as novel carbonic anhydrase inhibitors

We synthesized herein 16 compounds (SUT1-SUT16) as potential carbonic anhydrase (CA) inhibitors utilizing the tail-approach design. Based on this strategy, we connected benzenesulfonamide, the zinc-binding scaffold, to different urea moieties with the 1,3,4-thiadiazole ring as a linker. We obtained the target compounds by the reaction of 4-(5-amino-1,3,4-thiadiazol-2-yl)benzenesulfonamide with aryl isocyanates. Upon confirmation of their structures, the compounds were screened for their ability to inhibit the tumor-related human (h) isoforms human carbonic anhydrase (hCA) IX and XII, as well as the physiologically dominant hCA I and II. Most of the molecules demonstrated Ki values ≤ 10 nM with different selectivity profiles. The binding modes of SUT9, SUT10, and SUT5, the most effective inhibitors of hCA II, IX, and XII, respectively, were predicted by molecular docking. SUT16 (4-{5-[3-(naphthalen-1-yl)ureido]-1,3,4-thiadiazol-2-yl}benzenesulfonamide) was found to be the most selective inhibitor of the cancer-associated isoforms hCA IX and XII over the off-target isoforms, hCAI and II. The interaction dynamics and stability of SUT16 within hCA IX and XII were investigated by molecular dynamics simulations as well as dynophore analysis. Based on computational data, increased hydrophobic contacts and hydrogen bonds in the tail part of these molecules within hCA IX and XII were found as favorable interactions leading to effective inhibitors of cancer-related isoforms.

A novel molecularly imprinted electrochemical sensor based on quasi-three-dimensional nanomaterials Nb2CTx/AgNWs for specific detection of sulfadiazine

A novel molecularly imprinted electrochemical sensor (MIECS) was constructed for the specific detection of sulfadiazine (SDZ) in food. Niobium carbide (Nb2CTx) as a typical two-dimensional lamellar nanomaterial has good electrical conductivity and unique structure, which was assembled with one-dimensional silver nanowires (AgNWs) to form quasi-three-dimensional composite nanomaterials (Nb2CTx/AgNWs). As spacer material, AgNWs prevented the aggregation of Nb2CTx and the collapse of Nb2CTx layers. At the same time, a fast electron transport channel was constructed through the synergistic effect between nanomaterials the two. The Nb2CTx/AgNWs realized the enhancement of electrical signals. Molecularly imprinted polymers (MIPs) endowed the sensor with selectivity, achieving the specific detection of sulfadiazine. Under the optimal experimental conditions, the method has a wide linear range (1 × 10-8-1 × 10-4 mol L-1) and a low limit of detection (1.30 × 10-9 mol L-1). The sensor was used to detect sulfadiazine in pork, chicken, and feed samples, and the recovery was 82.61-94.87%. The results were in good agreement with the HPLC results, which proved the accuracy and practicability of the method.

Photocatalytic Sulfonylation: Innovations and Applications

Photosynthesis, converting sustainable solar energy into chemical energy, has emerged as a promising craft to achieve diverse organic transformations due to its mild reaction conditions, sustainability, and high efficiency. The synthesis of sulfonated compounds has drawn significant attention in the pharmaceuticals, agrochemicals, and materials industries due to the unique structure and electronic properties of the sulfonyl groups. Over the past decades, many photocatalytic sulfonylation reactions have been developed. In this review, the recent advances in photocatalyzed sulfonylation have been reviewed since 2020, with a primary focus on discussing reaction design and mechanism.

Classification, characteristics, harmless treatment and safety assessment of antibiotic pharmaceutical wastewater (APWW): A comprehensive review

The issues related to the spread of antibiotics and antibiotic resistance genes (ARGs) have garnered significant attention from researchers and governments. The production of antibiotics can lead to the emission of high-concentration pharmaceutical wastewater, which contains antibiotic residues and various other pollutants. This review compiles the classification and characteristics of antibiotic pharmaceutical wastewater (APWW), offers an overview of the development, advantages, and disadvantages of diverse harmless treatment processes, and presents a strategy for selecting appropriate treatment approaches. Biological treatment remains the predominant approach for treating APWW. In addition, several alternative methods can be employed to address the challenges associated with APWW treatment. On the other hand, the present safety assessment of the effluent resulting from APWW treatment is inadequate, necessitating more comprehensive research in this domain. It is recommended that researches in this area consider the issue of toxicity and antibiotic resistance as well. The PNECR model (similar to ecotoxicological PNECs but used to specifically refer to endpoints related to antimicrobial resistance) (Murray et al., 2024) is an emerging tool used for evaluating the antimicrobial resistance (AMR) issue. This model is, characterized by its simplicity and effectiveness, is a promising tool for assessing the safety of treated APWW.

Intermolecular Anti-Markovnikov Hydroamination of Alkenes with Sulfonamides, Sulfamides, and Sulfamates

A general method for the light-driven intermolecular anti-Markovnikov hydroamination of alkenes with primary sulfonamides, sulfamides, and sulfamates is presented. The reaction is mediated by a ternary catalyst system composed of an iridium(III) chromophore, a fluorinated alkoxide base, and a thiol H-atom donor. We hypothesize that the reactions proceed through a proton coupled electron-transfer (PCET) mechanism wherein implementation of the alkoxide base imparts additional thermochemical driving force for the homolytic activation of strong N-H bonds that were previously inaccessible using this methodology. This furnishes electrophilic N-centered radicals that subsequently interface with a wide range of unactivated alkenes for C-N bond formation. This protocol exhibits a broad substrate scope and great functional group tolerance, further highlighting the advantages of excited-state PCET as a platform for catalytic radical generation from common organic functional groups.

Metal-free efficient synthesis of aryl sulfonamides from N-hydroxy sulfonamide and amines

A simple and novel approach has been developed for the synthesis of sulfonamides from N-hydroxy sulfonamide. Notably, the iodine-tert-butyl hydroperoxide (TBHP) system efficiently promoted the sulfonylation reactions of N-hydroxy sulfonamides and amines via the oxidative cleavage of an S-N bond. A variety of aryl sulfonamides were prepared in moderate to good yields using readily available starting materials and the biomass-derived 2-MeTHF solvent. The present method has the advantages of using metal-free reagents, an eco-friendly medium, cost-effective reagents, wide substrate scope, and mild conditions.

Sandmeyer Chlorosulfonylation of (Hetero)Aromatic Amines Using DABSO as an SO2 Surrogate

Sulfonyl chlorides not only play a crucial role in protecting group chemistry but also are important starting materials in the synthesis of sulfonamides, which are in-demand motifs in drug discovery chemistry. Despite their importance, the number of different synthetic approaches to sulfonyl chlorides is limited, and most of them rely on traditional oxidative chlorination chemistry from thiol precursors. In this report, we disclose a novel Sandmeyer-type sulfonyl chloride synthesis from feedstock anilines and DABSO, used as a stable SO2 surrogate, in the presence of HCl and a Cu catalyst. The method works on a wide range of anilines and allows for the isolation of the sulfonyl chloride after aqueous workup or its direct conversion into the sulfonamide by simple addition of an amine after the completion of the Sandmeyer reaction. The scalability of this method was demonstrated on a 20 g scale, and the corresponding heterocyclic sulfonyl chloride was isolated in 80% yield and excellent purity.

Novel benzene sulfonamides with acetylcholinesterase and carbonic anhydrase inhibitory actions

A series of benzene sulfonamides 15-26 were synthesized and determined for their in vitro and in silico inhibitory profiles toward acetylcholinesterase (AChE) and carbonic anhydrases (CAs). Commercially available 3,4-dimethoxytoluene was reacted with chlorosulfonic acid to furnish benzene sulfonyl chloride derivatives. The reaction of substituted benzene sulfonyl chloride with some amines also including (±)-α-amino acid methyl esters afforded a series of novel benzene sulfonamides. In this study, the enzyme inhibition abilities of these compounds were evaluated against AChE and CAs. They exhibited a highly potent inhibition ability on AChE and -CAs (Ki values are in the range of 28.11 ± 4.55 nM and 145.52 ± 28.68 nM for AChE, 39.20 ± 2.10 nM to 131.54 ± 12.82 nM for CA I, and 50.96 ± 9.83 nM and 147.94 ± 18.75 nM for CA II). The present newly synthesized novel benzene sulfonamides displayed efficient inhibitory profiles against AChE and CAs, and it is anticipated that they may emerge as lead molecules for some diseases including glaucoma, epilepsy, and Alzheimer's disease.

Novel synthesis of the first new class of triazine sulfonamide thioglycosides and the evaluation of their anti-tumor and anti-viral activities against human coronavirus

Novel class of triazine sulfonamide thioglycosides was designed and synthesized. Those novel structures comprising three essential and pharmacological significant moieties such as the triazine, sulfonamide, and thioglycosidic scaffolds. The triazine sulfonamides were furnished via a direct approach starting from potassium cyanocarbonimidodithioate, then the corresponding triazine sulfonamide thioglycosides were generated using the peracylated α-d-gluco- and galacto-pyranosyl bromides. Anti-viral evaluation of compounds in vitro against HCoV-229E virus revealed that some compounds possess promising activity. Compounds 4a, 4b, 4d, 6d and 6e indicate from moderate to low antiviral activity against low pathogenic coronavirus 229E in comparison with remdesivir at a concentration of 100 µg/mL. Additionally their in vitro anti-proliferative effects against NCI 60 cancer cell lines cell lines were also investigated. Compound 4a, the most potent compound among the estimated compounds, revealed remarkably lowest cell growth promotion against CNS cancer SNB-75, and renal cancer UO-31.

Exploiting N-Centered Umpolung Reactivity of α-Iminomalonates for the Synthesis of N-Sulfenylimines and Sulfonamides

An efficient and interesting N-centered umpolung method has been disclosed to construct beneficial S-N bonds, furnishing N-sulfenylimines, which can readily be converted into the corresponding sulfonamide derivatives in a one-pot sequential operation. N-Sulfenylimines are potent intermediates in organic synthesis, whereas sulfonamides are of major molecular interest due to their rich biological activities and wide applicability in medicinal chemistry. Owing to the simple reaction conditions and setup, this protocol displays a broad and versatile substrate scope, resulting in excellent functional group tolerability toward the synthesis of both N-sulfenylimines and sulfonamides. A density functional theory (DFT) computed and experimentally supported convenient mechanism has been proposed for this unique method.

Synthesis and evaluation of hybrid sulfonamide-chalcones with potential antileishmanial activity

Leishmaniasis is an emerging tropical infectious disease caused by a protozoan parasite of the genus Leishmania. In this work, the molecular hybridization between a trimethoxy chalcone and a sulfonamide group was used to generate a series of sulfonamide-chalcones. A series of eight sulfonamide-chalcone hybrids were made with good yields (up to 95%). These sulfonamide-chalcones were tested against promastigotes of Leishmania amazonensis and cytotoxicity against mouse macrophages, which showed good antileishmanial activity with IC50  = 1.72-3.19 µM. Three of them (10c, 10g, and 10h) were also highly active against intracellular amastigotes and had a good selectivity index (SI > 9). Thus, those three compounds were docked in the cytosolic tryparedoxin peroxidase (cTXNPx) enzyme of the parasite, and molecular dynamics simulations were carried out. This enzyme was selected as a target protein for the sulfonamide-chalcones due to the fact of the anterior report, which identified a strong and stable interaction between the chalcone NAT22 (6) and the cTXNPx. In addition, a prediction of the drug-likeness, and the pharmacokinetic profile of all compounds were made, demonstrating a good profile of those chalcones.

Chemoselective Electrochemical Cleavage of Sulfonimides as a Direct Way to Sulfonamides

A new method for selective cleavage of sulfonimides into sulfonamides in high yields using a simple electrochemical approach is shown. As revealed by the electrochemical study, the aromatic sulfonimides can be selectively cleaved by electrolysis of the starting compound at a given potential (only -0.9 V vs SCE for the nosyl group). The high chemoselectivity was confirmed by preparative electrolysis, and the results were supported with DFT calculations of a set of substances bearing different sulfonimide functions. Moreover, various experimental setups together with other attempts to simplify the procedure were tested. Finally, the removal of the p-nosyl group from the corresponding sulfonimides proceeds smoothly regardless of the number of nosyl groups and the overall shape of the complex molecule. Thus, the method is interesting for use in the field of multifunctional molecules such as calix[n]arenes.

Development of a molecularly imprinted membrane for selective, high-sensitive, and on-site detection of antibiotics in waters and drugs: Application for sulfamethoxazole

Sulfonamides are among the widespread bacterial antibiotics. Despite this, their quick emergence constitutes a serious problem for ecosystems and human health. Therefore, there is an increased interest in developing relevant detection method for antibiotics in different matrices. In this work, a straightforward, green, and cost-effective protocol was proposed for the preparation of a selective molecularly imprinted membrane (MIM) of sulfamethoxazole (SMX), a commonly used antibiotic. Thus, cellulose acetate was used as the functional polymer, while polyethylene glycol served as a pore-former. The developed MIM was successfully characterized through scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The MIM was used as a sensing platform in conjunction with a smartphone for optical readout, enabling on-site, selective, and highly sensitive detection of SMX. In this way, a satisfactory imprinting factor of around 3.6 and a limit of detection of 2 ng mL-1 were reached after applying response surface methodologies, including Box-Behnken and central composite designs. Besides, MIM demonstrated its applicability for the accurate and selective detection of SMX in river waters, wastewater, and drugs. Additionally, the MIM was shown to be a valuable sorbent in a solid-phase extraction protocol, employing a spin column setup that offered rapid and reproducible results. Furthermore, the developed sensing platform exhibited notable regeneration properties over multiple cycles and long shelf-life in different storage conditions. The newly developed methodology is of crucial importance to overcome the limitations of classical imprinting polymers. Furthermore, the smartphone-based platform was used to surpass the typically expensive and complicated methods of detection.

Bypassing Sulfonyl Halides: Synthesis of Sulfonamides from Other Sulfur-Containing Building Blocks

This review disclosed synthetic approaches to sulfonyl amides from non-sulfonyl halogenated precursors. Known methods were systematized into groups and subgroups according to the type of starting organosulfur compound. Thiols, disulfides, and sulfonamides form a group of S(II)-containing precursors, which are used in oxidative amination reactions. An important and versatile group for oxidative amination is represented with S(IV)-containing compounds, i. e., sufinates, sulfinamides, DMSO, N-sulfinyl-O-(tert-butyl)hydroxylamine, etc. A series of S(VI)-containing precursors for amination reactions (except sulfonyl halides) include sulfonic acids, sulfonyl azides, thiosulfonates, and sulfones. All approaches are represented with the most prominent examples of the resulting sulfonamides, which could be obtained in high yields mostly via short reaction sequences. Promising electrochemical methods for the preparation of sulfonamides from thiols, disulfides, sulfonamides, sulfinic acid derivatives, and dimethyl sulfoxide under mild and green conditions are also highlighted.

Chemoselective Reactions of Functionalized Sulfonyl Halides

Chemoselective transformations of functionalized sulfonyl fluorides and chlorides are surveyed comprehensively. It is shown that sulfonyl fluorides provide an excellent selectivity control in their reactions. Thus, numerous conditions are tolerated by the SO2 F group - from amide and ester formation to directed ortho-lithiation and transition-metal-catalyzed cross-couplings. Meanwhile, sulfur (VI) fluoride exchange (SuFEx) is also compatible with numerous functional groups, thus confirming its title of "another click reaction". On the contrary, with a few exceptions, most transformations of functionalized sulfonyl chlorides typically occur at the SO2 Cl moiety.

Visible-Light-Induced Decarboxylative Aminosulfonylation of (Hetero)aryl Carboxylic Oxime Esters

Sulfonamides are important structures in pharmaceuticals, agrochemicals, and organocatalysts, yet the rapid and benign synthesis of these compounds is still a great challenge. Herein we report a photoinduced method for synthesizing sulfonamides from (hetero)aryl carboxylic acid oxime esters. This reaction proceeds via one-pot cascade radical-radical cross-coupling by energy-transfer-mediated photocatalysis. A wide substrate scope including (hetero)aryl substrates and late-stage modification of pharmaceutical molecular entities reveal its generality.

Design and Synthesis of Ketenimine Sulfonamide Conjugates through Multicomponent Reactions; A Combined Cytotoxic Analysis and Computational Exploration

Multicomponent reactions involving zwitterion generated from dimethyl acetylenedicarboxylate, aryl sulfonamide, and isocyanide to generate sulfonamide-conjugated ketenimines is reported. The synthetic strategy adopted is highly atom economical and stereoselective. Ketenimine sulfonamide analogues are key intermediates for further synthetic conversions to generate a combinatorial library of compounds. Furthermore, sulfonamide compounds are known to possess a broad spectrum of biological applications. All the novel molecules synthesized exhibit the potential to target the nonhomologous DNA end-joining (NHEJ) pathway with cytotoxic ability. Computational studies compliment the in vitro biological assays of the 8 small-molecule inhibitors. DNA double-strand breaks (DSBs) are considered as the most lethal among different DNA damages. NHEJ repairs about 70% of the DSBs generated in cells within mammals. The DNA-dependent protein kinase catalytic subunit is one of the PI3 kinases associated with NHEJ. Compounds DK01-DK08 were investigated for their ability to induce cancer cell death by treating with two leukemic cell lines where NHEJ is high. Results showed that bromoaryl (DK04)- and nitroaryl (DK05)-conjugated molecules showed excellent biological activity, having IC50 values of ∼2 μM in Nalm6 cell lines.

One-Pot Synthesis of Sulfonamides from Unactivated Acids and Amines via Aromatic Decarboxylative Halosulfonylation

The coupling of carboxylic acids and amines to form amide linkages is the most commonly performed reaction in the pharmaceutical industry. Herein, we report a new strategy that merges these traditional amide coupling partners to generate sulfonamides, important amide bioisosteres. This method leverages copper ligand-to-metal charge transfer (LMCT) to convert aromatic acids to sulfonyl chlorides, followed by one-pot amination to form the corresponding sulfonamide. This process requires no prefunctionalization of the native acid or amine and extends to a diverse set of aryl, heteroaryl, and s-rich aliphatic substrates. Further, we extend this strategy to the synthesis of (hetero)aryl sulfonyl fluorides, which have found utility as "click" handles in chemical probes and programmable bifunctional reagents. Finally, we demonstrate the utility of these protocols in pharmaceutical analogue synthesis.

Photocatalytic Carboxylate to Sulfinamide Switching Delivers a Divergent Synthesis of Sulfonamides and Sulfonimidamides

sulfinamides, sulfonamides, and sulfonimidamides are in-demand motifs in medicinal chemistry, yet methods for the synthesis of alkyl variants that start from simple, readily available feedstocks are scarce. In addition, bespoke syntheses of each class of molecules are usually needed. In this report, we detail the synthesis of these three distinct sulfur functional groups, using readily available and structurally diverse alkyl carboxylic acids as the starting materials. The method harnesses alkyl radical generation from carboxylic acids using acridine photocatalysts and 400 nm light with subsequent radical addition to sulfinylamine reagents, delivering sulfinamide products. Using the N-alkoxy sulfinylamine reagent t-BuO-NSO as the radical trap provides common N-alkoxy sulfinamide intermediates, which can be converted in a divergent manner to either sulfonamides or sulfonimidamides, by treatment with sodium hydroxide, or an amine, respectively. The reactions are scalable, tolerate a broad range of functional groups, and can be used for the diversification of complex biologically active compounds.

New sustainable antimicrobial chitosan hydrogels based on sulfonamides and its nanocomposites: Fabrication and characterization

Chitosan (Ch), a linear cationic biopolymer, has a broad medical applications. In this paper, new sustainable hydrogels (Ch-3,Ch-5_a,Ch-5_b) based on chitosan/sulfonamide derivatives 2-chloro-N-(4-sulfamoylphenethyl) acetamide (3) and/or 5-[(4-sulfamoylphenethyl) carbamoyl] isobenzofuran-1,3-dione (5) were prepared. Hydrogels (Ch-3, Ch-5_a, Ch-5_b) were loaded (Au,Ag,ZnO) NPs to form its nanocomposites to improve the antimicrobial efficacy of chitosan. The structures of hydrogels and its nanocomposites were characterized using different tools. All hydrogels displayed irregular surface morphology in SEM, however hydrogel (Ch-5_a) revealed the highest crystallinity. The highest thermal stability was shown by hydrogel (Ch-5_b) compared to chitosan. The nanocomposites represented nanoparticle sizes <100 nm. Antimicrobial activity was assayed for hydrogels using disc diffusion method exhibited great inhibition growth of bacteria compared to chitosan against S. aureus, B. subtilis and S. epidermidis as Gram-positive, E. coli, Proteus, and K. pneumonia as Gram-negative and antifungal activity against Aspergillus Niger and Candida. Hydrogel (Ch-5_b) and nanocomposite hydrogel (Ch-3/Ag NPs) showed higher colony forming unit (CFU) and reduction% against S. aureus and E. coli reaching 97.96 % and 89.50 % respectively in comparison with 74.56 % and 40.30 % for chitosan respectively. Overall, fabricated hydrogels and its nanocomposites enhanced the biological activity of chitosan and it can be potential candidate as antimicrobial drugs.

A review of the influence of soil minerals and organic matter on the migration and transformation of sulfonamides

Sulfonamides (SAs) are common antibiotics that are widely present in the environment and can easily migrate in the environment, so they pose an environmental risk. Minerals and organic matter influence the antibiotic migration and transformation in sewage treatment plants, activated sludge, surface water, and soil environment. In the present paper, the influence of the process and mechanism of minerals and organic matter on the adsorption, degradation, and plant uptake of SAs in soil were summarized. In the impact process of mineral and organic matter on the SAs migration and transformation, the pH value is undoubtedly the most important factor because it determines the ionic state of SAs. In terms of influence mechanisms, the minerals absorb SAs well via cation exchange, complexation, H-bonding, and cation bridging. Mineral photodegradation is also one of the primary removal methods for SAs. Soil organic matter (SOM) can significantly increase the SAs adsorption. The adsorption forces of SAs and SOM or dissolved organic matter (DOM) were very similar, but SOM decreased SAs mobility in the environment, while DOM increased SAs availability. DOM generated active substances and aided in the photodegradation of SAs. This review describes the effects of minerals and organic matter on the fate of SAs in soil, which is useful in controlling the migration and transformation of SAs in the soil environment.

Photoinduced Vicinal 1,2-Difunctionalization of Olefins for the Synthesis of Alkyl Sulfonamides

Alkyl sulfonamides are an important class of bioactive molecules. Historical syntheses have relied on multistep sequences incorporating harsh reaction conditions. Photochemical methods have been limited to hydrosulfamoylation, installing only one substituent across an olefin. Herein, radical/polar crossover (RPC) is used to establish the first multicomponent 1,2-difunctionalization reaction incorporating a sulfonamide moiety and a second reaction partner. This protocol, exemplified on a range of olefins, utilizes various commercial sulfamoyl chlorides and organotrifluoroborates as coupling partners.

Identification of sulfonamide compounds active on the insect nervous system: Molecular modeling, synthesis and biological evaluation

Insect nicotinic acetylcholine receptors (nAChRs) are a recognized target for insecticide design. In this work, we have identified, from a structure-based approach using molecular modeling tools, ligands with potential selective activity for pests versus pollinators. A high-throughput virtual screening with the Openeye software was performed using a library from the ZINC database, thiacloprid being used as the target structure. The top sixteen molecules were then docked in α6 cockroach and honeybee homomeric nAChRs to check from a theoretical point of view relevant descriptors in favor of pest selectivity. Among the selected molecules, one original sulfonamide compound has afterward been synthesized, together with various analogs. Two compounds of this family have been shown to behave as activators of the cockroach cholinergic synaptic transmission.

Ethyl ester/acyl hydrazide-based aromatic sulfonamides: facile synthesis, structural characterization, electrochemical measurements and theoretical studies as effective corrosion inhibitors for mild steel in 1.0 M HCl

In this research paper, aromatic sulfonamide-derived ethyl ester (p-TSAE) and its acyl hydrazide (p-TSAH) were directly synthesized, characterized, and employed for the first time as prospective anticorrosive agents to protect mild steel in 1.0 M HCl conditions. The corrosion efficiency was probed by electrochemical methods including polarization, impedance, and frequency modulation measurements. Optimal efficiencies of 94% and 92% were detected for the hydrazide and ester, respectively, revealing excellent corrosion inhibition. Moreover, both the hydrazide and ester molecules combat the cathodic and anodic reactions correspondingly in a mixed-type manner. The electron transfer (ET) at the inhibitor/metal interface was evaluated using DFT at the B3LYP/6-31g(d,p) level. Natural bond orbital analysis (NBO) and frontier molecular orbital analysis (FMO) calculations showed superior capabilities of the synthesized inhibitors to easily reallocate charge into the metal surface. However, the hydrazide molecules showed slightly better inhibition efficiency than the ester due to the strong interaction between the lone pairs of the nitrogen atoms and the d-orbitals of the metal. The chemical hardness of the hydrazide and ester are 2.507 and 2.511 eV, respectively, in good accordance with the recorded electrochemical inhibition efficiencies for both molecules. Good and straightforward correlations between the experiments and calculations are obtained.

Direct Reaction of Nitroarenes and Thiols via Photodriven Oxygen Atom Transfer for Access to Sulfonamides

Sulfonamide is a common motif in medicines and agrochemicals. Typically, this class of functional groups is prepared by reacting amines with sulfonyl chlorides that are presynthesized from nitro compounds and thiols, respectively. Here, we report a novel strategy that directly couples nitro compounds and thiols to form sulfonamides atom- and redox-economically. Mechanistic studies suggest our reaction proceeds via direct photoexcitation of nitroarenes that eventually transfers the oxygen atoms from the nitro group to the thiol unit.

FDA-Approved Small Molecules in 2022: Clinical Uses and Their Synthesis

This review describes the recently FDA-approved drugs (in the year 2022). Many of these products contain active moieties that FDA had not previously approved, either as a single ingredient or as part of a combination. These products frequently provide important new therapies for patients with multiple unmet diseases. The diverse small molecules are described according to the date of approval and their syntheses is discussed. This review comprises classical chemical scaffolds together with innovative drugs such as a deuterium-containing drug.

Synthesis of I(III)/S(VI) reagents and their reactivity in photochemical cycloaddition reactions with unsaturated bonds

The development of novel methodologies for the introduction of the sulfoxonium group under mild conditions is appealing but remains underexplored. Herein we report the synthesis of a class of hypervalent iodine reagents with a transferrable sulfoxonium group. These compounds enable mixed iodonium-sulfoxonium ylide reactivity. These well-defined reagents are examined in visible-light-promoted cyclization reactions with a wide range of unsaturated bonds including alkenes, alkynes, nitriles, and allenes. Two distinct cyclization pathways are identified, which are controlled by the substituent of the unsaturated bond. The cycloaddition protocol features simple operation, mild reaction conditions, and excellent functional group tolerance, affording a broad range of sulfoxonium-containing cyclic structures in moderate to excellent yields. Furthermore, the sufoxonium group in the product can be transformed into diverse functional groups and structural motifs via single electron transfer and transition-metal catalysis.

Structure and Computational Studies of New Sulfonamide Compound: {(4-nitrophenyl)sulfonyl}tryptophan

Synthesis of sulfonamide through an indirect method that avoids contamination of the product with no need for purification has been carried out using the indirect process. Here, we report the synthesis of a novel sulfonamide compound, ({4-nitrophenyl}sulfonyl)tryptophan (DNSPA) from 4-nitrobenzenesulphonylchloride and L-tryptophan precursors. The slow evaporation method was used to form single crystals of the named compound from methanolic solution. The compound was characterized by X-ray crystallographic analysis and spectroscopic methods (NMR, IR, mass spectrometry, and UV-vis). The sulfonamide N-H NMR signal at 8.07–8.09 ppm and S-N stretching vibration at 931 cm−1 indicate the formation of the target compound. The compound crystallized in the monoclinic crystal system and P21 space group with four molecules of the compound in the asymmetric unit. Molecular aggregation in the crystal structure revealed a 12-molecule aggregate synthon sustained by O-H⋯O hydrogen bonds and stabilised by N-H⋯O intermolecular contacts. Experimental studies were complemented by DFT calculations at the B3LYP/6-311++G(d,p) level of theory. The computed structural and spectroscopic data are in good agreement with those obtained experimentally. The energies of interactions between the units making up the molecule were calculated. Molecular docking studies showed that DNSPA has a binding energy of −6.37 kcal/mol for E. coli DNA gyrase (5MMN) and −6.35 kcal/mol for COVID-19 main protease (6LU7).