Benzene Sulfonamide Research Articles

Surface Analysis of Inhibitor Film Formed by 4-Amino-N-(1,3-thiazol-2-yl) Benzene Sulfonamide on Carbon Steel Surface in Acidic Media

ABSTRACT Inhibitive properties of the antibacterial sulfa drug sulfathiazole—IUPAC name being 4-amino-N-(1,3-thiazol-2-yl) benzene sulfonamide—on the corrosion of carbon steel in 1.0 M HCl solution were investigated using weight loss measurements, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Sulfathiazole is a good adsorption inhibitor, and the inhibition efficiency increases with increasing concentration. Adsorption is spontaneous and is best described by Temkin isotherm. XPS analysis showed, at this stage, that the main product of corrosion is a nonstoichiometric Fe3+ oxide/oxyhydroxide consisting of a mixture of Fe2O3, α, and γ-FeO(OH) and/or Fe(OH)3, where α, γ-FeO(OH) is the main phase.

English

In the present study, a series of N-substituted sulfonamides have been synthesized. The reaction of benzene sulfonyl chloride (1) with O-anisidine (2) yielded N-(2-methoxyphenyl) benzenesulfonamide (3), which on bromination with bromine in the presence of acetic acid gave N-(4,5-dibromo-2-methoxyphenyl)benzenesulfonamide (6). The two products (3) and (6) further on treatment with alkyl halides/acyl halide in the presence of sodium hydride yielded thirteen different N-substituted sulfonamides. The compounds were characterized by IR, EIMS and 1H-NMR and screened against acetyl cholinesterase, butyryl cholinesterase and lipoxygenase enzymes. The results revealed that N-butyl-N-(4, 5-dibromo-2-methoxyphenyl)benzene sulfonamide (6d) and N-pentyl-N-(4,5-dibromo-2-methoxy phenyl)benzenesulfonamide (6e) exhibited good inhibitory potential against lipoxygenase.

Vibrational spectroscopic and quantum chemical calculations of ( E)- N-Carbamimidoyl-4-((naphthalen-1-yl-methylene)amino)benzene sulfonamide

FT-IR and FT-Raman spectra of ( E)- N-Carbamimidoyl-4-((naphthalen-1-yl-methylene)amino)benzene sulfonamide were recorded and analyzed. The vibrational wavenumbers were computing at various levels of theory. The data obtained from theoretical calculations are used to assign vibrational bands obtained experimentally. The results indicate that B3LYP method is able to provide satisfactory results for predicting vibrational frequencies and structural parameters. The calculated first hyperpolarizability is comparable with reported values of similar derivatives and is an attractive object for future studies of non-linear optics. The geometrical parameters of the title compound are in agreement with that of similar derivatives.

ChemInform Abstract: Synthesis of Some New 1,3,5‐Trisubstituted Pyrazolines Bearing Benzene Sulfonamide as Anticancer and Antiinflammatory Agents.

AbstractThe title compounds (III) are tested for their anticancer and antiinflammatory activity.

Solubilities of benzene sulfonamide in supercritical CO 2 in the absence and presence of cosolvent

Solubilities of benzene sulfonamide in supercritical CO 2 were measured by using dynamic method at temperature ranging from 308.15 to 328.15 K over a pressure range of 11.0–21.0 MPa. The experimental data in binary system were correlated with eight semi-empirical equations. The calculated result shows that the equation proposed by Adachi and Lu (A–L) provides the best correlation to the experimental data. The AARD (%) for A–L equation is 5.53. The thermodynamic properties (total enthalpy Δ H, sublimation enthalpy Δ H sub. and solvation enthalpy Δ H solv.) of solid solute were obtained. The cosolvent investigated in this work was ethanol, ethylene glycol and ethyl acetate, respectively. The solubilities in ternary system were determined with molar fraction of 3.5% (cosolvent) at 308.15 K over a pressure range of 11.0–21.0 MPa. The enhancement factor of each cosolvent was calculated. The experimental data in ternary system were correlated by using T–G equation and modified Sovova equation.

A Comparative Molecular Field (CoMFA) Studies on Carbonic Anhydrase Inhibitor hCA IX-Tumor-Associated (Hypoxia)

Comparative molecular field analysis (CoMFA) was carried out on Carbonic anhydrase inhibitor hCA IX- tumor-associated (Hypoxia). Database contains a series of aromatic benzene sulfonamides incorporating 1, 3, 5-triazine moieties derivative. This study correlates the inhibitory activities of structurally related 1, 3, 5-triazine moiety derivatives derived to Tripos standard in CoMFA. The data base alignment conformation yielded good predictive CoMFA model (r2cv = 0.82, F-value = 460.320, r2pred = 0.787 with five components). The contour maps obtained from 3D - QSAR studies were appraised for the activity trends of the molecules analyzed. The result indicates that the steric and electrostatic features play a significant role in the carbonic anhydrase inhibition activity and potency of these compounds. The data generated from the present study can be used as putative pharmacophore in the design of novel, potent and selective hCA IX inhibitors.

Determination of structural and vibrational spectroscopic properties of 2-, 3-, 4-nitrobenzenesulfonamide using FT-IR and FT-Raman experimental techniques and DFT quantum chemical calculations

In this work, the molecular conformation and vibrational analysis of 2-, 3-, 4-nitrobenzenesulfonamide (abbreviated as 2-, 3-, 4-NBSA) were presented for the ground state using experimental techniques (FT-IR and FT-Raman) and density functional theory (DFT) employing B3LYP exchange correlation with the 6-311++G(d,p) basis set. The complete assignments of fundamental vibrations were performed on the basis of the experimental results and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. The effects of the nitro group substituent on the characteristic benzene sulfonamides bands in the spectra were discussed. Raman activities calculated by DFT method have been converted to the corresponding Raman intensities using Raman scattering theory. Optimized structure of compounds were interpreted and compared with the earlier reported experimental values for studied molecules. The observed and the calculated geometric parameters and vibrational wavenumbers were compared and found to be in good agreement.

Osmium(VIII)-Catalyzed Kinetics and Mechanism of Indigo Carmine Oxidation by Chloramine-B in Basic Medium

Indigo carmine (IC) or sodium indigotin disulfonate is a natural dye that finds applications in clinical diagnosis, chemistry and biology. The osmium(VIII)-catalyzed oxidation of IC by chloramine-B (CAB) in alkaline solutions has been spectrophotometrically monitored at the indigo carmine λmax of 610 nm at 298 K. The reaction stoichiometry has been found to be 1:4 (mol:mol), resulting in the formation of major products that are the sodium salt of sulfonated anthranilic acid (SAA) and benzenesulfonamide (BSA). The reaction shows a first-order dependence of the rate on [IC], a fractional-order dependence each on [Os(VIII)] and [OH−], and a zero-order dependence each on [CAB], [BSA], and [SAA]. The variation of the ionic strength of the reaction medium has a negligible effect on the rate. Based on the effect of temperature in the range 288–313 K, activation parameters are evaluated from Arrhenius and Eyring plots. A mechanism consistent with the observed kinetic and activation data has been proposed and a rate law has been derived.

Synthesis and biological evaluation of some new 2-pyrazolines bearing benzene sulfonamide moiety as potential anti-inflammatory and anti-cancer agents

Eight novel 2-pyrazolines ( 2a–h) were synthesized by the reaction of appropriate chalcones/flavanones with 4-hydrazinonbenzenesulfonamide hydrochloride and tested for anti-inflammatory and anti-cancer activities. Two compounds 2c and 2e showed good anti-inflammatory activity which is comparable to the reference drug celecoxib in carrageenan-induced rat paw edema bioassay and found safe from the point of view of ulcer induction. Compounds 2c and 2e showed very mild inhibition against the enzymatic activity of ovine COX-1 and COX-2 (in vitro). The compounds 2c and 2f exhibited considerable antitumor activity against tested 60 human tumor cell lines. Specifically, compound 2f exhibited promising anti-proliferative activity with GI 50 values less than 2 μM particularly against MOLT-4 (1.94), SR (1.28) in leukemia cancer, EKVX (1.88) in non small cell lung cancer, COLO 205 (1.69) in colon cancer.

Synthesis and characterization of novel dioxoacridine sulfonamide derivatives as new carbonic anhydrase inhibitors

Novel dioxoacridine sulfonamide compounds were synthesized from reaction of cyclic 1,3-diketones, sulfanilamide (4-amino benzene sulfonamide) and aromatic aldehydes. The structures of these compounds were confirmed by using spectral analysis (IR, H-NMR, 13C-NMR, and mass). Human carbonic anhydrase isoenzymes (hCA I and hCA II) were purified from erythrocyte cells by affinity chromatography. The inhibitory effects of sulfanilamide, acetazolamide (AAZ), and newly synthesized sulfonamides on hydratase and esterase activities of these isoenzymes have been studied in vitro. The IC50 values of compounds for esterase activity are 0.71–0.11 µM for hCA I and 0.45–0.12 µM for hCA II, respectively. The Ki values of these inhibitors were determined as 0,38–0,008 µM for hCA I and 0,19–0,001 µM for hCA II, respectively.

FT-IR and computational study of (E)-N-carbamimidoyl-4-((2-formylbenzylidene)amino)benzene sulfonamide

The infrared spectrum of (E)-N-carbamimidoyl-4-((2-formylbenzylidene)amino)benzene sulfonamide has been recorded and analysed. Geometry and harmonic vibrational wavenumbers were calculated theoretically using Gaussian 03 set of quantum chemistry codes. Calculations were performed at the Hartree–Fock and DFT levels of theory using the standard 6-31G ∗ basis. The calculated wavenumbers (B3LYP) agree well with the observed wavenumbers. The data obtained from vibrational wavenumber calculations are used to assign vibrational bands found in infrared spectrum of the studied molecule. The red-shift of the NH stretching band in the infrared spectrum from the computed wavenumber indicates the weakening of the NH bond. The NH stretching band has split into a doublet in the IR spectrum owing to the Davydov coupling between neighboring units. The geometrical parameters of the title compound are in agreement with the reported similar derivatives. Calculated infrared intensities and the first hyperpolarizability are reported. The calculated first hyperpolarizability is comparable with the reported value of similar structures and may be an attractive object for further studies on non linear optics.

A Direct Comparison of the MM-GB/SA Scoring Procedure and Free-Energy Perturbation Calculations Using Carbonic Anhydrase as a Test Case: Strengths and Pitfalls of Each Approach.

MM-GB/SA scoring and free energy perturbation (FEP) calculations have emerged as reliable methodologies to understand structural and energetic relationships to binding. In spite of successful applications to elucidate the structure-activity relationships for few pairs of ligands, the reality is that the performance of FEP calculations has rarely been tested for more than a handful of compounds. In this work, a series of 13 benzene sulfonamide inhibitors of carbonic anhydrase with binding free energies determined by isothermal titration calorimetry was selected as a test case. R(2) values of 0.70, 0.71, and 0.49 with the experiment were obtained with MM-GB/SA and FEP simulations run with MCPRO+ and Desmond, respectively. All methods work well, but the results obtained with Desmond are inferior to MM-GB/SA and MCPRO+. The main contrast between the methods is the level of sampling, ranging from full to restricted flexibility to single conformation for the complexes in Desmond, MCPRO+, and MM-GB/SA, respectively. The current and historical results obtained with MM-GB/SA qualify this approach as a more attractive alternative for rank-ordering; it can achieve equivalent or superior predictive accuracy and handle more structurally dissimilar ligands at a fraction of the computational cost of the rigorous free-energy methods. As for the large theoretical dynamic range for the binding energies, that seems to be a direct result of the degree of sampling in the simulations since MCPRO+ as well as MM-GB/SA are plagued by this. Van't Hoff analysis for selected pairs of ligands suggests that the wider scoring spread is not only affected by missing entropic contributions due to restricted sampling but also exaggerated enthalpic separation between the weak and potent compounds caused by diminished shielding of electrostatic interactions, thermal effects, and protein relaxation/strain.

Synthesis of some new 1,3,5-trisubstituted pyrazolines bearing benzene sulfonamide as anticancer and anti-inflammatory agents

Thirteen new 2-pyrazoline derivatives bearing benzenesulfonamide moiety (2a-m) were synthesized by condensing appropriate chalcones with 4-hydrazinonbenzenesulfonamide hydrochloride and tested for anticancer and anti-inflammatory actions. According to the protocol of the National Cancer Institute (NCI) in vitro disease-oriented human cells screening panel assay compounds 2b, 2c, 2e, 2f and 2g exhibited considerable antitumor activities against the entire tested tumor cell lines and showed effective growth inhibition GI(50) (MG-MID) values of 2.63, 2.57, 6.61, 3.31 and 2.57μM, respectively, beside a cyclostatic activity TGI (MG-MID) 9.54, 8.51, 24.0, 19.9 and 8.71μM, respectively. Two compounds 2g and 2k showed more potent anti-inflammatory activity than celecoxib at 5h in carrageenan-induced rat paw edema bioassay. These compounds (2g and 2k) proved to have superior gastrointestinal safety profiles as compared to celecoxib, when tested for their ulcerogenic effects. Compounds 2g and 2k showed no inhibition against the enzymatic activity of bovine COX-2 (in vitro).

Development and characterization of plasticized polyamides by fluid and solid plasticizers

Polyamides are semicrystalline polymers that are useful in a wide range of applications in the plastics industry. Some applications require higher flexibility and improved workability of polyamides; thus, a plasticization approach that eases compounding and processing procedures and produces better desired product properties can be utilized. Common plasticizers are high‐boiling liquid esters, but solid plasticizers also have been considered. The present research has focused on plasticization of nylon 66/6 (80/20) copolymer by using selected low molecular weight organic materials. Plasticization of the copolyamide was studied with glycerin mono stearate, benzene sulfonamide, and methyl 4‐hydroxybenzoate as the solid plasticizers and diethylhexyl phthalate as the liquid plasticizer. The materials were prepared and characterized by thermal, mechanical, dynamic, rheological, and morphological properties. The experimental results were supported by simulated polymer and plasticizer interactions using molecular dynamic simulations. Plasticization and antiplasticization phenomena were observed and discussed. The plasticizers were classified by their efficiency in reducing Tg and by modification of the other polyamide properties. Copyright © 2011 John Wiley & Sons, Ltd.

Amino-caprolactam γ-secretase inhibitors showing potential for the treatment of Alzheimer’s disease

Herein we describe the structure-activity relationship (SAR) of amino-caprolactam analogs derived from amino-caprolactam benzene sulfonamide 1, highlighting affects on the potency of γ-secretase inhibition, selectivity for the inhibition of APP versus Notch processing by γ-secretase and selected pharmakokinetic properties. Amino-caprolactams that are efficacious in reducing the cortical Aβ(x-40) levels in FVB mice via a single 100 mpk IP dose are highlighted.

Studies of tricyclic piperazine/piperidine furnished molecules as novel integrin α vβ 3/α IIbβ 3 dual antagonists using 3D-QSAR and molecular docking

The development of injectable integrin α vβ 3/α IIbβ 3 dual antagonists attracts much attention of research for treating of acute ischemic diseases in recent years. In this work, based on a dataset composed of 102 tricyclic piperazine/piperidine furnished dual α vβ 3 and α IIbβ 3 antagonists, a variety of in silico modeling approaches including the comparative molecular field analysis (CoMFA), comparative similarity indices analysis (CoMSIA), and molecular docking were applied to reveal the requisite 3D structural features impacting the biological activities. Our statistical results show that the ligand-based 3D-QSAR models for both the α vβ 3 and α IIbβ 3 studies exhibited satisfactory internal and external predictability, i.e., for the CoMFA models, results of Q 2 = 0.48, R ncv 2 = 0.87 , R pred 2 = 0.71 for α vβ 3 and Q 2 = 0.50, R ncv 2 = 0.85 , R pred 2 = 0.72 for α IIbβ 3 analysis were obtained, and for the CoMSIA ones, the outcomes of Q 2 = 0.55, R ncv 2 = 0.90 , R pred 2 = 0.72 for α vβ 3 and Q 2 = 0.52, R ncv 2 = 0.88 , R pred 2 = 0.74 for α IIbβ 3 were achieved respectively. In addition, through a comparison between 3D-QSAR contour maps and docking results, it is revealed that that the most crucial interactions occurring between the tricyclic piperazine/piperidine derivatives and α vβ 3/α IIbβ 3 receptor ligand binding pocket are H-bonding, and the key amino acids impacting the interactions are Arg214, Asn215, Ser123, and Lys253 for α vβ 3, but Arg214, Asn215, Ser123 and Tyr190 for α IIbβ 3 receptors, respectively. Halogen-containing groups at position 15 and 16, benzene sulfonamide substituent at position 23, and the replacement of piperazine with 4-aminopiperidine of ring B may increase the α vβ 3/α IIbβ 3 antagonistic activity. The potencies for antagonists to inhibit isolated α vβ 3 and α IIbβ 3 are linear correlated, indicating that similar interaction mechanisms may exist for the series of molecules. To our best knowledge this is the first report on 3D-QSAR modeling of these dual α vβ 3/α IIbβ 3 antagonists. The results obtained should provide information for better understanding of the mechanism of antagonism and thus be helpful in design of novel potent dual α vβ 3/α IIbβ 3 antagonists.

Evaluation of the Antitumor and Radiosynthetizing Activity of a Novel Quinoline Sulfonamide Derivative (PIQSA) as a Histone Deacetylase Inhibitor

Inhibition of histone deacetylases (HDACs) is emerging as a new strategy in cancer therapy. In the present work a novel pyrimido-quinoline benzene sulfonamide (PIQSA compound) was designed and synthesized postulating its ability to inhibit HDAC enzyme in cancer cells. This study was designed to examine the in vitro anti-tumor efficacy of PIQSA against Ehrlich Ascite carcinoma cells (EAC) and three of the human cancer cell lines (H460), brain (U251) and liver (HepG2). The results of Cytotoxic assays showed that PIQSA exhibited in vitro antitumor activity in a dose dependant manner. The tumor growth delay studies indicating that PIQSA resulted in significant regression in tumor growth, which was more pronounced when PIQSA treatment accompanied with radiation exposure. Also, the efficacy of PIQSA to influence radiation response in Ehrlich solid carcinoma (ESC) tumors was estimated. The results suggest that PIQSA exhibited antitumor activities and strong radioenhancing properties associated with inhibition of HDAC activity, DNA fragmentation followed by apoptotic cell death, preferential cell loss of cells particularly in G1/G0 phase through an apoptotic pathway.

Free‐solution interaction assay of carbonic anhydrase to its inhibitors using back‐scattering interferometry

Back-scattering interferometry (BSI) is a label-free, free-solution, small-volume technique used for characterizing binding interactions, which is also relevant to a growing number of biosensing applications including drug discovery. Here, we use BSI to characterize the interaction of carbonic anhydrase enzyme II with five well-known carbonic anhydrase enzyme II inhibitors (± sulpiride, sulfanilamide, benzene sulfonamide, dansylamide, and acetazolamide) in the presence of DMSO. Dissociation constants calculated for each interaction were consistent with literature values previously obtained using surface plasmon resonance and fluorescence-based competition assays. Results demonstrate the potential of BSI as a drug-screening tool which is fully compatible with DMSO and does not require immobilization or labeling, therefore allowing binding interactions to be characterized in the native state. BSI has the potential for reducing labor costs, sample consumption, and assay time while providing enhanced reliability over existing techniques.

Molecular structure and vibrational investigation of benzenesulfonic acid methyl ester using DFT (LSDA, B3LYP, B3PW91 and MPW1PW91) theory calculations

The FT-Raman and FT-IR spectra for benzenesulfonic acid methyl ester (BSAME) have been recorded in the region 4000–100 cm −1 and compared with the harmonic vibrational frequencies calculated using DFT (LSDA, B3LYP, B3PW91 and MPW1PW91) method by employing 6-311G (d, p) basis set with appropriate scale factors. IR intensities and Raman activities are also calculated by DFT (LSDA, B3LYP, B3PW91 and MPW1PW91) methods. Optimized geometries of the molecule have been interpreted and compared with the reported experimental values for sulfonic acid and some substituted sulfonic acids. The experimental geometrical parameters show satisfactory agreement with the theoretical prediction from DFT. The scaled vibrational frequencies at LSDA/B3LYP/6-311G (d, p) seem to coincide with the experimentally observed values with acceptable deviations. The theoretical spectrograms (IR and Raman) have been constructed and compared with the experimental FT-IR and FT-Raman spectra. Some of the vibrational frequencies of the sulfonic acid are effected upon profusely with the methyl substitution in comparison to benzene sulfonamide and these differences are interpreted.

Polymorphism in Secondary Benzene Sulfonamides

The role of about 20 different solvents in the crystallization of polymorphs for 13 N-phenyl benzene sulfonamides was studied. Five compounds (1, 2, 3, 7, and 11) are dimorphic, and one is trimorphic (6). All the crystalline solids were characterized by powder and single crystal X-ray diffraction, thermal analysis, hot stage microscopy, and IR and Raman spectroscopy. The phase transition from a metastable form to the stable form was examined visually for two compounds (1, 11) on a HSM and confirmed by differential scanning calorimetry and X-ray diffraction. The N−H···O hydrogen bond catemer (chain) and dimer (cyclic) motifs of the sulfonamide group were analyzed as the main difference between polymorphs of 1, 3, and 6. Weaker C−H···O interactions differentiate the molecular packing of other polymorphic systems. Accordingly, these crystal structures are referred to as synthon polymorphs. The occurrence of N−H···O catemer and dimer synthon in secondary sulfonamides is compared with crystal structures in the...