Sulfonamide Products Research Articles

Indium Promotes Direct Sulfonamidation of Unactivated Alcohols.

An improved protocol has been developed for the direct sulfonamidation of unactivated alkyl alcohols using In(OTf)3 as a Lewis acid catalyst. Although the established methods using Lewis or Brønsted acids have been well-studied for the direct functionalization of alcohols, their substrate scope mainly focuses on the π-activated alcohols. In this reaction, unactivated aliphatic alcohols were evaluated and afforded the desired sulfonamide products with good to excellent yields.

Chemodivergent Synthesis of Sulfonamide and Sulfones from N-Tosylhydrazones by Switching Catalyst and Temperature.

A catalyst- and temperature-controlled selective synthesis of sulfonamide and sulfones from N-tosylhydrazones and MBH carbonates has been developed. The use of palladium catalysts exclusively leads to sulfonamide products at room temperature, whereas the selective synthesis of sulfones is dominant for a temperature-controlled coupling reaction without palladium catalysis. Importantly, the catalyst- or temperature-controlled reaction exhibits high nucleophilicity rather than carbene reactivity in these transformations.

First discovery of sulfonamides derivatives with acetylcholinesterase inhibitory activity in fungus Pestalotiopsis sp. HNY36-1D

Three rare natural sulfonamide products, sargassulfamide A (1), together with two unreported sulfonamides pestasulfamides B (2) and A (3) were obtained from mangrove endophytic fungus Pestalotiopsis sp. HNY36-1D under the guidance of chemical and biological autoradiography. Their structures were determined by 1D and 2D NMR, HR-ESI-MS, as well as single crystal X-ray diffraction. It was noteworthy that sulfonamide derivatives were obtained from metabolites of fungi for the first time. In bioassay, compounds 1 and 3 showed moderate acetylcholinesterase (AChE) inhibitory activities with IC50 values 28.41 and 11.94 μM, respectively. The structure-activity relationships (SARs) analysis suggested that the existence of hydrogen atom on the N atom of sulfonamide derivatives and the closed loop of cyclic dipeptide were beneficial to the activity. The molecular docking studies indicated that 1 and 3 were near the center of the active pocket of AChE, while 2 was at the edge of the protein due to the large steric hindrance.

Radical–Radical Cross-Coupling Assisted N–S Bond Formation Using Alternating Current Protocol

Radical–Radical Cross-Coupling Assisted N–S Bond Formation Using Alternating Current Protocol

New hydronaphthalene-sulfonamide derivatives: Synthesis, antimicrobial evaluation and QSAR study

In the present work, authors successfully prepared potent antimicrobial agents of new tetrahydronaphthalene-sulfonamide derivatives, derived from new easily synthetic route of 3-methoxy-8-oxo-5,6,7,8-tetrahydronaphthalene-2-sulfonyl chloride 2. Preparation method of this compound has not been published yet, however it is available commercially expensively, which motivated us to innovate new efficient and facile method for its preparation. All the synthesized compounds were tested for in vitro antimicrobial inhibitory activities against a panel of Gram-positive, Gram-negative bacterial pathological strains and Candida Albicans. Compound 2 showed poor activity towards all of the tested pathogenic strains, but it is easily modified and converted from biologically inactive compound to highly active sulfonamide products 5a-f, or moderately active compounds 3a-k. Cytotoxic evaluation of the promising candidates 5d and 5e showed marked safety profile towards the human normal cells. QSAR study for the new compounds was carried out and was compatible with the antimicrobial results.

Copper-boryl mediated transfer hydrogenation of N-sulfonyl imines using methanol as the hydrogen donor

B 2 Pin 2 -assisted copper-catalyzed transfer hydrogenation of aromatic sulfonylimines has been achieved, delivering a variety of aryl/heteroaryl sulfonamides in good to excellent yields under mild reaction conditions and with methanol as the hydrogen source. Mechanistic studies suggest that the reaction may proceed via a transient α-borylated intermediate, followed by protodeboration to afford the sulfonamide products. • Copper-mediated catalysis. • Transfer hydrogenation. • Aryl sulfonamides. • Heteroaryl sulfonamides.

Guest-Controlled Incommensurate Modulation in a Meta-Rigid Metal-Organic Framework Material.

Structural transitions of host systems in response to guest binding dominate many chemical processes. We report an unprecedented type of structural flexibility within a meta-rigid material, MFM-520, which exhibits a reversible periodic-to-aperiodic structural transition resulting from a drastic distortion of a [ZnO4N] node controlled by the specific host–guest interactions. The aperiodic crystal structure of MFM-520 has no three-dimensional (3D) lattice periodicity but shows translational symmetry in higher-dimensional (3 + 2)D space. We have directly visualized the aperiodic state which is induced by incommensurate modulation of the periodic framework of MFM-520·H2O upon dehydration to give MFM-520. Filling MFM-520 with CO2 and SO2 reveals that, while CO2 has a minimal structural influence, SO2 can further modulate the structure incommensurately. MFM-520 shows exceptional selectivity for SO2 under flue-gas desulfurization conditions, and the facile release of captured SO2 from MFM-520 enabled the conversion to valuable sulfonamide products. MFM-520 can thus be used as a highly efficient capture and delivery system for SO2.

Survey of veterinary prescribing for poultry disease.

To enable better antimicrobial stewardship, it is important to know what the patterns of prescribing behaviour are and what diseases or reasons antibiotics are being prescribed. A prescribing guideline (i.e. recommended best practice for writing prescriptions) developed by the Australian poultry veterinarians exists. However, it is not a prescribing guideline detailing treatments for the commonly observed bacterial diseases in commercial poultry. An online survey was deployed to all registered veterinarians and members of the Australian Veterinary Poultry Association to identify prescribing behaviours for the most frequently observed bacterial diseases of poultry. A total of 39 survey responses were received. Most surveys were started but not completed; 13 (33%) were completed with 18 (46%) containing some information on prescribing. The most frequent treatment responses were for Escherichia coli in both layers and broilers, chronic respiratory disease (CRD), fowl cholera and spotty liver in layers and necrotic enteritis in broilers. Treatments described were for products registered for poultry use, within the recommended label dose and duration of treatment (Tables 1, 2). Unsurprisingly, tetracyclines and amoxycillin, followed by lincomycin and trimethoprim sulfonamide products were the most frequently reported treatment options. Inappropriate treatments were reported for salmonellosis and one veterinarian recommended the use of enrofloxacin for the treatment of fowl cholera. Information provided by respondents will enable the initial development of prescribing guidelines for both commercial and small poultry flocks. Importantly, it identified less than optimal prescribing behaviour for some diseases, a reliance on one class of antibiotic more than others and a failure to utilise all antimicrobial classes potentially available for treatment. Critically, the survey identified a lack of treatment options for bacterial disease in poultry. The most important bacterial diseases of poultry remain the same; effective alternatives for antibiotic treatment are required and old diseases, thought once gone, are reinventing themselves as problems for the future. Surveys of prescribing behaviours are essential for identifying diseases of high priority, changes in treatments and response to treatment and to identify areas for targeted antimicrobial stewardship, and research needs.

Green and Facile Reaction of Gabapentin with Sulfonyl Chlorides to Synthesize Lactams and Sulfonamides Derivatives in Aqueous Medium

In the current research, a facile and green one pot synthesis of new gabapentin-lactams (G2-G8) has been achieved by reacting gabapentin (G1) with a variety of sulfonyl chlorides. The new lactamization protocol is furnished under the green solvent i.e., water and reaction was completed in a short period of time by just stirring at room temperature. Whereas in some cases, annulation could not happen and furnished un-cyclized sulfonamide products (G9-G12). The structures of the targeted compounds were established by elemental analysis, FT-IR, 1H-NMR and mass spectrometry. The crystals of some new lactams (G2, G3, G4, and G8) were also evaluated by single crystal X-ray diffraction. Keywords: Crystal structure, facile reaction, gabapentin, green synthesis, lactams, sulfonamides.

Direct Sulfonamidation of Primary and Secondary Benzylic Alcohols Catalyzed by a Boronic Acid/Oxalic Acid System

The direct sulfonamidation of primary and secondary benzylic alcohols catalyzed by a 2,3,4,5‐tetrafluorophenylboronic acid/oxalic acid co‐catalytic system was examined. The reaction proceeds under mild conditions with readily available starting materials and has been shown to be gram‐scalable without significant decrease of yield. Both primary and secondary benzylic alcohols were evaluated and afforded the desired sulfonamide products with good to excellent yields.

Kinetic Resolution of 2-Substituted Indolines by N-Sulfonylation using an Atropisomeric 4-DMAP-N-oxide Organocatalyst.

The first catalytic kinetic resolution by N-sulfonylation is described. 2-Substituted indolines are resolved (s=2.6-19) using an atropisomeric 4-dimethylaminopyridine-N-oxide (4-DMAP-N-oxide) organocatalyst. Use of 2-isopropyl-4-nitrophenylsulfonyl chloride is critical to the stereodiscrimination and enables facile deprotection of the sulfonamide products with thioglycolic acid. A qualitative model that accounts for the stereodiscrimination is proposed.

Kinetic Resolution of 2‐Substituted Indolines by N‐Sulfonylation using an Atropisomeric 4‐DMAP‐N‐oxide Organocatalyst

AbstractThe first catalytic kinetic resolution by N‐sulfonylation is described. 2‐Substituted indolines are resolved (s=2.6–19) using an atropisomeric 4‐dimethylaminopyridine‐N‐oxide (4‐DMAP‐N‐oxide) organocatalyst. Use of 2‐isopropyl‐4‐nitrophenylsulfonyl chloride is critical to the stereodiscrimination and enables facile deprotection of the sulfonamide products with thioglycolic acid. A qualitative model that accounts for the stereodiscrimination is proposed.

Assessing Process Mass Intensity and Waste via an aza-Baylis–Hillman Reaction

A synthetic procedure is outlined where upper-level undergraduate organic chemistry students perform a two-week, semimicroscale aza-Baylis–Hillman reaction to generate an allylic sulfonamide product. Students evaluate several green chemistry reaction metrics of industrial importance (process mass intensity (PMI), E factor, and reaction mass efficiency) and specifically learn the pivotal role that PMI plays in improving operational sustainability. Advantages and disadvantages of the various metrics are highlighted within the context of a multicomponent transformation eliciting current research activity.

Systematic suspect screening and identification of sulfonamide antibiotic transformation products in the aquatic environment.

The formation of environmental sulfonamide transformation products (TPs) has only been investigated for very selected compounds, and their transformation pathways are incompletely elucidated. Given their homologous series, it is likely that similar transformation reactions occur for all sulfonamides. It has recently been demonstrated for sulfamethoxazole (SMX) that its derivative TPs retain antibiotic activity. Unfortunately, TP reference standards are often not available and a number of TPs are still unknown. Therefore, in the present study, a generic scheme was developed to predict 29 potential TPs of sulfonamide antibiotics via identification of the major transformation and breakdown reactions. Mass shifts were calculated for each transformation allowing for a suspect screening using LC/QTOF. Based on the structural elucidation of the parent sulfonamide product ion spectra, five characteristic product ions could be predicted for each of 15 derivative TPs. The predictions were confirmed with reference standards of SMX TPs as well as with data of TPs of further sulfonamides reported in literature. In a final step, samples of activated sludge biotransformation experiments were screened for suspect TPs of two sulfonamides. In total, 13 ecotoxicologically relevant TPs could be tentatively identified by use of the product ion predictions and LC/QTOF.

A practical method for regiocontrolled one-carbon ring contraction

A practical and efficient method for the perfluorobutanesulfonyl azide-mediated one-carbon ring contraction of cyclic enoxysilanes is described. High-yielding procedures for the elaboration of the resulting N-acyl sulfonamide products are reported.

Direct monitoring of chemical transformations by combining thin layer chromatography with nanoparticle-assisted laser desorption/ionization mass spectrometry

A nanomaterial-assisted method that combines thin layer chromatography (TLC) with matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) was developed to directly monitor chemical transformations. A substrate-dependent extraction strategy was studied and successfully used to identify target molecules from the depths of a developed TLC plate. By using this strategy, a hydrophobic sample of interest was enriched on the surface of the TLC plate in the presence of acetonitrile, in contrast to using water and methanol to identify hydrophilic samples. The successful enrichment of samples by specific solvents provided stable desorption/ionization efficiencies of compounds of interest and led to very good sensitivity near the attomole scale. The method was then used to monitor 4-dimethylaminopyridine (DMAP)-catalyzed acylation in preparation of bifunctional sulfonamides. The labile DMAP-acyl intermediate and final sulfonamide product were clearly identified on TLC plates without external purification or sample preparation. Furthermore, in combination with collision-induced dissociation (CID) to provide structural information, the technique was successfully used in the natural product discovery of anti-inflammatory flavonoids from Helminthostachys zeylanica, a traditional Chinese herb. The newly proposed method provides a very low background from silica supports or organic matrices in the low molecular weight range (100-1000 Da). The technique may greatly accelerate studies of metabolomics, drug discovery, and organic synthesis.

Evaluation and application of surfactants synthesized from asphalt components

The synthesis, characterization, surface activity and applications of nonionic surfactants derived from the asphalt components (maltenes M) are presented. These compounds were synthesized by the sulfonation of (maltene), then the prepared maltene sulfonic acid (MS) was reacted with hexadecylamine giving maltene sulfonamide product (A) which undergoes an alkali-catalyzed ethoxylation at (135–150°C). Several surfactants (M-10 to M-40) were formed with different ethylene oxide units (from 10 up to 40) and were characterized by molecular weight determinations, elemental analyses and FTIR analysis. Surface tension, as a function of concentration of the surfactants in the aqueous media, was measured at 25°C. From these measurements, the critical micelle concentration (CMC), the maximum surface excess concentration (Гmax), Minimum area per molecule (Amin), effectiveness of surface reduction (ПCMC) and the efficiency (pC20) were calculated. The prepared surfactants were applied as emulsifying agents for making asphalt emulsions. Storage stability, (Saybolt Furol) viscosity, settlement (water content difference %), coating ability and water resistance were measured. The results indicated that M-20 (maltene sulfonamide ethoxylated with 20 units of ethylene oxides) gives a maximum stability.

Enantioselective silver-catalyzed propargylation of imines

A catalytic enantioselective method for the propargylation of aldimines is described. A silver catalyst ligated by a bidentate phoshpine is utilized to provide good yields and high ee's for a variety of substrates. Homopropargylic sulfonamide products undergo facile silver-mediated cyclization to generate 2-pyrrolines, useful intermediates for alkaloid synthesis.

Stereoselective Radical Addition of an Acetal to Sterically Tuned Enantiomerically Pure N-Sulfinyl Imines

Enantiomerically enriched sulfonamides were synthesized by the radical addition of an acetal to enantiomerically pure N-sulfinyl imines using dimethylzinc-air and boron trifluoride diethyl etherate. Higher levels of stereocontrol were observed by using a mesitylenesulfinyl group. Furthermore, an amine and an amino alcohol with high enantiomeric purity were obtainable from the sulfonamide product.

Copper-Catalyzed Amidation of Allylic and Benzylic CH Bonds

[Structure: see text] A copper-catalyzed amidation of allylic and benzylic C-H bonds with both primary and secondary sulfonamides is described. The reaction is applicable to the coupling of a diverse set of hydrocarbon species with aryl, heteroaryl, and alkyl sulfonamides and is tolerant of a variety of functional groups. Mechanistic insight has been gained through the isolation of a benzylic acetate intermediate, which was demonstrated to undergo facile conversion to the substituted sulfonamide product under copper catalysis.