Sulfamic Acids Research Articles

Structural insights into ketanserin salts with aliphatic acids and their physiochemical properties

Ketanserin (KTS), a BCS class II drug with low solubility, was paired with acidic coformers (maleic, fumaric, adipic, and sulfamic acids) to create stable salts through wet granulation. XRD, DSC, TGA, UV, and Hirshfeld analysis confirmed that these salts enhanced solubility.

Influence of Alkyd Composite Coatings with Polyaniline Doped with Different Organic Acids on the Corrosion of Mild Steel

Composite coatings prepared by mixing 5 wt.% polyaniline with commercial alkyd-based paints were applied on carbon steel. The polyaniline emeraldine chloride salt was prepared by procedure recommended by IUPAC, including deprotonation by ammonia hydroxide, and reprotonation with sulfamic, succinic, citric, and acetic acids with different doping degrees or oxidation states. The steel samples with base and composite coatings were immersed in 3% NaCl and the corrosion current density was determined after 96 h in situ using the ASTM 1,10-phenanthroline method. The samples were also inspected by optical microscopy. It was shown that the composite coatings reduced the possibility of blister formations and delamination. The corrosion current density and the appearance of the corrosion products, whose area was determined by ImageJ software, closely followed the initial oxidation state of the polyaniline. It was also shown that damaged composite coatings with higher degrees of oxidized (doped) polyaniline were more prone to formation of corrosion products. The role of the initial state of the polyaniline is discussed. It is suggested that such behavior could be connected to the oxygen reduction reaction mechanism that proceeds mainly via two electron paths on the polyaniline particles, releasing a much smaller amount of hydroxyl ions, which is responsible for the delamination and blister formation of the commercial coatings.

The synergistic effect of organic and inorganic sulfonic acids promotes new particle formation

New particle formation (NPF) represents a significant source of aerosol particles in the atmosphere; however, the NPF mechanisms remain uncertain, hindering the understanding and assessment of its environmental effects. Hence, we investigated the nucleation mechanisms in multicomponent systems including two inorganic sulfonic acids (ISAs), two organic sulfonic acids (OSAs), and dimethylamine (DMA) by combining quantum chemical (QC) calculations and molecular dynamics (MD) simulations, and evaluated the comprehensive effect of ISAs and OSAs on DMA-driven NPF. The QC results showed that the (Acid)2(DMA)0–1 clusters were strongly stable, and the (ISA)2(DMA)1 clusters exhibited higher stability than the (OSA)2(DMA)1 clusters because ISAs (sulfuric and sulfamic acids) provided more H-bonds and stronger proton transfer than OSAs (methanesulfonic and ethanesulfonic acids). ISAs readily engaged in dimer formation, whereas the stability of trimer clusters was mainly regulated by the synergistic effects of ISAs and OSAs. OSAs participated in cluster growth earlier than ISAs. Our results revealed that ISAs promote cluster formation, whereas OSAs facilitate the growth of clusters. The synergistic effect of ISAs and OSAs should be further investigated in areas with high [OSAs]: [ISAs].

Impacts of sulfonic acids on fungal manganese oxide production

Microbial manganese (Mn) oxidation plays a critical role in Mn(III/IV) oxide formation in modern day environmental systems. These oxidation processes and resulting biominerals are sensitive to aqueous conditions, such as pH and dissolved constituent concentrations. With Mn and sulfur (S) biogeochemical cycling closely linked in many environmental systems, and dissolved organic sulfur comprising a substantial pool of total sulfur in several environments, the impact of dissolved organic sulfur compounds on Mn redox processes is important to consider. Sulfonic acids, environmentally ubiquitous organosulfur compounds, play substantial roles in S cycling in many natural and contaminated systems. Research to assess the effects of these abundant sulfonic acids on Mn biogeochemical cycling, microbial Mn oxidation processes, and Mn biominerals is needed for understanding and predicting the impact of coupled S and Mn biogeochemical cycles, particularly in environments with dynamic redox gradients or in anthropogenically contaminated systems. Further, with research on microbial and abiotic Mn oxidation processes often using aminosulfonic acids to control pH, understanding the impact of such sulfonic acids on microbial Mn oxidation processes is critical. Several recent studies found that commonly used zwitterionic N substituted aminosulfonic acids, known as Good’s buffers, such as HEPES and MES, can alter abiotic birnessite sheet structures. Here we investigate the impact of two sulfonic acids with broad applications to natural and contaminated sites as well as laboratory settings (HEPES and MES) on fungal Mn oxidation relative to a carbonate buffer and a buffer-free control by three Ascomycete fungi known to oxidize Mn(II): Stagonospora sp. SRC1lsM3a, Paraphaeosphaeria sporulosa AP3s5–JAC2a, and Plectosphaerella cucumerina DS2psM2a2. Structural analyses of the products show that sulfonic acids promote Mn oxidation by P. cucumerina, producing hexagonally symmetric phyllomanganates analogous to hexagonal birnessite or c–disordered H+ birnessite [(Ca,Na,K)(Mn4+,Mn3+,□)O2nH2O], with solid–associated Mn(II) bound to vacancy sites and biomass, while in their absence almost all Mn remains as either aqueous Mn(II) or solid–associated Mn(II) bound to biomass. In contrast, sulfonic acids exert the opposite effect on Mn oxidation by P. sporulosa, with their presence suppressing Mn(II) oxidation to Mn(IV), likely leading to the formation of mycogenic bixbyite (Mn3+2O3) while the buffer–free control forms a poorly crystalline phyllo- or tectomanganate. Meanwhile, all treatments exert a minimal effect on Mn(II) uptake from solution and Mn oxidation with Stagonospora sp., with all experimental systems and controls forming poorly crystalline, hexagonally symmetric phyllomanganates. The fact that the sulfonic acids here studied exert similar effects on Mn oxidation, but substantially different effects for each fungus, suggests they affect Mn oxidation via mechanistically similar pathways that are likely dependent on interactions with fungal exudates (which vary from species to species) or specific fungal Mn oxidation processes. Interestingly, for all fungi, MES increases Mn(III) in the resulting biominerals, while the carbonate buffer consistently decreases Mn(III). These results clearly demonstrate that sulfonic acids not only alter Mn oxide structures, as has been previously noted in abiotic studies, but can interfere with Mn oxidation reactions themselves, highlighting the incredible sensitivity of both Mn oxide structures and the Mn oxidation process to the aqueous environment.

Оптимизация состава ингибитора коррозии на основе имидазолинов для защиты оборудования в углекислотной и кислотной средах

This study focuses on the protective properties of an imidazoline-based corrosion inhibitor with the introduction of thiourea and potassium iodide additives into its composition, depending on the nature of the environment. The aggressive environment wasa model of reservoir water saturated with carbon dioxide, as well as hydrochloric and sulfamic acids. The effectivenessof the inhibitor was evaluated by gravimetric method under dynamic and static conditions in carbon dioxide and acidic environment, respectively. As a result of the experiment, regularities were obtained for the influence of individual compounds on the mechanismof metal inhibition in environment with different properties.

Comprehensive Study of the Action of Corrosion Inhibitors Based on Quaternary Ammonium Compounds in Solutions of Hydrochloric and Sulfamic Acids

Acid treatments are one of the methods for intensifying oil and gas production. Corrosion is a significant factor affecting the performance of oilfield equipment. There are many different methods of preventing corrosion, but corrosion inhibitors are most commonly used in industry. The protective effect of the inhibitor is directly determined by the effective adsorption of surfactants on the metal surface. For an indirect assessment of the adsorption of the inhibitor, a comprehensive research method is proposed based on the determination of the interfacial tension of acid compositions and steel plates’ contact angle of wetting after corrosion tests. It was found that in hydrochloric acid the adsorption of the inhibitor IC-1 reaches a maximum after 6 h, an increase in the acid concentration in the range of 5–15% wt. has a negative effect on the activity of the inhibitor. For sulfamic acid, the maximum adsorption of the IC-2 inhibitor is observed after 24 h, an increase in acid concentration has a positive effect on surfactants.

STUDY OF THE SELECTION OF EFFECTIVE CORROSION INHIBITORS FOR VARIOUS ACIDS

Corrosion is one of the complications in the acidizing of the bottomhole zone of the well. Corrosion damage can lead to accidents and product loss. One of the most effective ways to protect metal equipment from corrosion is the use of corrosion inhibitors. Cationic surfactants are mainly used because they are capable of forming protective films on the surface of metals. In this work, studies were carried out to determine the effectiveness of industrial corrosion inhibitors in hydrochloric and sulfamic acids in concentrations of 5, 10, 15 (% wt.). As a result, it was found that in hydrochloric acid, corrosion damage is suppressed due to the adsorption of the inhibitor on the metal surface, while in sulfamic acid there are competing processes of adsorption of sulfamate ions and surfactants.

Interfacial Phenomena on the Phase Boundary Between Hydrocarbon Systems and Acids

A study was carried out on aspects of phenomena on the interfacial boundary of acids and hydrocarbon systems of different complexity. These phenomena were evaluated relative to the interfacial tension measured by the pendant drop method. We discovered peculiarities of the interaction of hydrochloric and sulfamic acids with individual hydrocarbons as well as complex hydrocarbon systems. The complex dependence of the interfacial tension on the composition and properties of the hydrocarbon phase, type and concentration of the acid, and the chemical composition of asphaltenes was elucidated.

Effects of variable deoxygenation on trace element bioaccumulation and resulting metabolome profiles in the blue mussel (Mytilus edulis)

The dissolved oxygen concentration of the world’s oceans has systematically declined by 2% over the past 50 years, and there has been a notable commensurate expansion of the global oxygen minimum zones (OMZs). Such wide-scale ocean deoxygenation affects the distribution of biological communities, impacts the physiology of organisms that may affect their capacity to absorb and process contaminants. Therefore, the bioaccumulation efficiencies of three contrasting radionuclides, 110mAg, 134Cs and 65Zn were investigated using controlled aquaria in the blue mussel Mytilus edulis under three contrasting dissolved oxygen regimes: normoxic; 7.14 mg L−1, reduced oxygen; 3.57 mg L−1 and hypoxic 1.78 mg L−1 conditions. Results indicated that hypoxic conditions diminished 110mAg uptake in the mussel, whereas depuration rates were not affected. Similarly, hypoxia appeared to cause a decrease in the 65Zn bioaccumulation rate, as evidenced by both weakened uptake and rapid elimination rates. Effects of hypoxia on the metabolome of mussels were also explored by untargeted Nuclear Magnetic Resonance (NMR) spectroscopic methods. The metabolic response was characterised by significantly greater abundance of several amino acids, amino sulfonic acids, dicarboxylic acids, carbohydrates and other metabolites in the lowest oxygen treatment, as compared to the higher oxygen treatments. Clearance rates significantly dropped in hypoxic conditions compared to normoxia. Results suggest that hypoxic conditions, and even partly moderate hypoxia, alter ventilation, an-aerobic, oxidative and osmoregulation metabolism of this mussel, which may further influence the trace element bioaccumulation capacity.

Изучение гидролиза и осадкообразования в кислотных составах на основе сульфаминовой кислоты

This article presents the results of a study of the hydrolysis of sulfamic acid and the elaboration of acidic compositions that are characterized by reduced sedimentation compared to mud acid. The effect of complexing compounds on the hydrolysis of sulfamic acid is considered, the hydrolysis of sulfamic acid and sulfamates is compared, and the secondary sedimentation of sulfamic acid and mud acid compositions is compared using the formation of hexafluorosilicates. The hydrolysis intensity of sulfamic acid and ammonium sulfamate was determined by the mass of sediments formed during the reaction of hydrolysis products with calcium chloride. The mass of calcium sulfate formed is proportional to the rate of hydrolysis of sulfamic acid. The process of dissolution of the quartz component of the terrigenous formation was studied using the gravimetric method. Differences in influence of EDTA, HEDP, and NTP on sedimentation prevention of the products of sulfamic acid hydrolysis were studied by the example of reactions with Ca2+. It was shown that compositions with NTP are characterized by a lower sediments formation. The ratio of NTP concentration and the hydrolysis rate of sulfamic acid is shown. Differences in the hydrolysis rate of compositions based on sulfamic acid and sulfamates were determined at a temperature of 80°C. It was shown that sulfamates are characterized by a lower rate of hydrolysis. Differences in quartz solubility were determined for compositions based on sulfamic and sulfuric acids, differences in the reactions kinetics were shown. It has been established that acid compositions based on sulfamic acid are characterized by less sedimentation rate being compared with acid compositions based on hydrochloric acid by the example of hexafluorosilicates formation.

Aspects of Interaction of Surfactant—Acid Compositions at Phase Boundary with Hydrocarbons

Most part of all additives to technological fluids for acid treatments of oil-extracting wells are surfactants. One of approaches to assess the behavior of surfactants in these compositions is to determine the interfacial tension of their solutions at the interface with hydrocarbons. The interfacial tension of surfactant—acid compositions based on hydrochloric and sulfamic acids and also on distilled water without addition of acids. The interfacial tension was determined at the boundary with n-octane, kerosene, and oil with different polarities and contents of natural surfactants. It was shown that n-octane and kerosene are model systems that allow conditional comparison in activity between surfactants. A dependence was found of the interfacial tension of a surfactant—acid formulations on the nature of an acid: sulfamic acid affects the activity of surfactants positively, and hydrochloric acid, negatively. The interfacial tension parameter being determined is strongly affected by the type of a surfactant. It was shown that the nonionogenic surfactant Neonol AF 9–12 shows the smallest values of the interfacial tension in the formulations based on distilled water, and the anionic surfactant Nezhegol, in acid formulations, which is due to the interaction of the functional group of a surfactant with hydroxonium ions present in solution.

Synthesis and properties of water-dispersible polyisocyanates carrying sulfonate

A series of N-alkylated aminosulfonic acids (NASAs) were synthesized with 1,4-butane sultone and primary amines and then reacted with hexamethylene diisocyanate trimer to obtain water-dispersible polyisocyanates (WDPs). Two-component waterborne polyurethane (2K-WPU) coatings were finally prepared by the reaction of WDPs and aqueous hydroxyl resins. The structures and properties of WDPs and 2K-WPU coatings were characterized. The effects of the categories and amounts of NASAs on the properties of WDPs and 2K-WPU coatings, including viscosities, water resistance and transparency, were investigated. The results showed that the average molecular weights and viscosities of the WDPs increased with the increase in the amounts and molecular weights of NASAs. 3-(Cyclohexylamino)-1-propanesulfonic acid possesses a high molecular weight, resulting in low-concentration –SO3 per mass, so a high concentration up to 3.5 wt% was needed to meet water-dispersible requirements. On the other hand, 3-isobutylamino-1-propanesulfonic acid (IBAPS) has high-concentration –SO3 per mass and only a low concentration (2.5 wt%) was required to offer satisfactory water dispersibility. 2K-WPU film cured by IBAPS-WDP displayed high gloss, good transparency and excellent water resistance owing to suitable steric hindrance and high content of –SO3H per mass.

Análise da ação de ácidos sobre ictiólitos da Formação Santana, Cretáceo Inferior da Bacia do Araripe, Nordeste do Brasil

Fossils are of great importance for building knowledge of the history of life on Earth. However, it demands a careful handling from its collecting at the field to curatorship in laboratory and its incorporation in a collection. Preparation, a part of that process, evolves the removal of the fossils from the rock matrix, through mechanic and/or chemical attrition. Despite the relevance of such procedure, the access to its knowledge keeps itself relatively restricted to paleontology laboratories, lacking such type of publications. Then, this work was realized aiming to test the utilization of different types and concentrations of acids in preparation process of calcareous fossils. The tests with acetic, hydrochloric, phosphoric and sulfamic acids were executed in twelve fragments of calcareous concretions (ichthyolites) of the Santana Formation, Lower Cretaceous of the Araripe Basin. Acetic acid had showed itself the most appropriated for the treatment of calcareous concretions for its elongated and soft action.

Comparing sulphamic acid to acetic and formic acids for the preparation of large mesozoic marine reptile fossils, and a method for monitoring residual acid and salt removal following acid preparation

Chemical preparation is an important technique in palaeontology that uses a dilute aqueous acid solution to remove calcareous matrix from fossils, but which leads to the evolution of salts as a by-product. Acid preparation is usually undertaken using formic and acetic acids, whereas sulphamic acid has only rarely been considered. Sulphamic acid is a strong acid, with many industrial uses, but which has fewer health and safety concerns, and produces fewer irritant fumes, than formic or acetic acids. Three comparative procedures were undertaken to understand the action of sulphamic acid in relation to formic and acetic acids, using calcareous matrix from Colombian (South American) large Mesozoic marine reptiles. The results of these procedures indicate sulphamic acid acts in a comparable manner to formic acid, and more rapidly than acetic acid, in terms of rate of matrix removal. Afourth procedure investigated the removal of acid and salt residues following sulphamic acid preparation of a Colombian large Mesozoic marine reptile fossil, a process essential for the long-term survival of any acid prepared specimen. The fossil was immersed in type 1 deionized water, and increasing electrical conductivity was used as a proxy for ionic leaching. The results imply the preparators 'rule of thumb' of soaking a specimen in water for three times the length of time spent in the acid solution, is inadequate to ensure satisfactory removal of acid and salt residues. Although tested on a specimen prepared using sulphamic acid, the technique for post-preparation ion removal is equally be applicable to all fossils prepared using sulphamic, formic or acetic acids in aqueous solution.

Nano-Silica@PVC-Bonded N-Ethyl Sulfamic Acid as a Recyclable Solid Catalyst for the Hydroxyalkylation of Phenol with Formaldehyde to Bisphenol F

Abstract Sulfamic acid functionalized PVC-coated nano-silica (NS) catalyst (NS@PVC-EDA-SO3H) was prepared via multi-step treatment processes and characterized by FT-IR, N2 adsorption-desorption, TGA/DTG, XRD, TEM, STEM-EDS, as well as acid-base back-titration. The hydroxyalkylation of phenol with formaldehyde to bisphenol F was employed to evaluate in detail its acid catalysis performances. The results indicated that the newly constructed NS@PVC-EDA-SO3H possessed richer short mesoporous to macroporous channels and highly exposed sulfamic acids and could exhibit excellent hydroxyalkylation activity and reusability owing to fast mass transfer and reaction rates for the conversion of substrates, as well as excellent structural and chemical stabilities. This new solid acid was obviously superior to the conventional homogeneous concentrated sulfuric acid and heterogeneous sulfonated resin catalysts in catalytic activity and reusability, which could achieve a remarkable formaldehyde conversion (99.9%) and selectivity of bisphenol F (94.5%) under optimal hydroxyalkylation conditions. Furthermore, it could also be recovered easily and used repeatedly at least nine times without an obvious decrease in activity.

Toward the development of an innovative descaling and corrosion inhibiting solutions to protect mild steel equipment: an experimental and theoretical approach

This work proposes a mixture of sulfamic and perchloric acids as a descaling solution and cetyltrimethyl ammonium bromide (CTAB) and imidazole for the improvement in the corrosion resistance of mild steel. The experiments were carried out at different temperatures using mass loss and electrochemical techniques. The samples were characterized by inductively coupled plasma spectrometry, SEM-EDS, and X-ray diffraction techniques. The study showed that CTAB and imidazole can serve as the efficient corrosion inhibitors for mild steel in descaling solution and were found to follow the model of Langmuir adsorption isotherm. Potentiodynamic polarization was performed at temperature 295, 305, 315, and 325 K, and it can be concluded that the CTAB/imidazole acted as mixed type corrosion inhibitors. Electrochemical impedance spectroscopy studies revealed that increase in imidazole concentration, resulted into the increased polarization resistance with simultaneous lowering of double-layer capacitance values. Computational techniques were used to support experimental results.

A Facile and Green Synthesis of 2,4,6-Triarylpyridine Derivatives Using the Modified Mesoporous Organic Polymer Based on Calix [4]Resorcinarene: As an Efficient and Reusable Heterogeneous Acidic Catalyst

The work describes an efficient one-pot synthesis of 2,4,6-trisubstituted pyridine derivatives through a three-component catalytic reaction. The procedure involves mesoporous organic polymer based on calix[4]resorcinarene in and functionalized by N-propyl sulfamic acids a solid acid catalyst. Excellent yields, short reaction times, catalyst reusability, and easy reaction handling under solvent-free and mild acidic conditions are the most important advantages of the present protocol. The acidic catalyst was characterized by a number of spectroscopic methods such as Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy and elemental CHNS analysis.

Distribution of Paraffin Hydrocarbons and Asphaltenes in Acidic Water-Oil Emulsion

Asphaltenes and solid paraffins isolated from various layers of acidic water-oil emulsions obtained by mixing an oilfield emulsion with 15% solutions of hydrochloric and sulfamic acids with or without addition of Fe(III) have been studied by elemental analysis, IR and EPR spectroscopy, gas–liquid chromatography, and calorimetry. In acidic water-oil emulsions, the high-molecular-weight petroleum components have not been found to concentrate at the oil/water interface; however, a change in their composition has been revealed, which is more pronounced in the presence of Fe(III). The formation of diamagnetic complexes of the paramagnetic centers of asphaltenes with Fe(III) has been detected.

Asymmetric syntheses of (R)-4-halo-6,6a,7,8,9,10-hexahydro-5H-pyrazino[1,2-a][1,n]naphthyridines, important 5-HT2C agonist precursors

Asymmetric syntheses of N-protected (R)-4-halo-6,6a,7,8,9,10-hexahydro-5H-pyrazino[1,2-a][1,n]naphthyridines, advanced intermediates for the synthesis of highly potent and selective 5-HT2C agonists, are described. The key transformation involves ring opening of N-protected bicyclic sulfamidate (R)-hexahydro-3H-pyrazino[1,2-c][1,2,3]oxathiazine 1,1-dioxide with (4-halo-2-fluoropyridin-3-yl)lithiums or (3-bromo-5-fluoropyridin-4-yl)lithium. In situ hydrolyses of the resultant sulfamic acids and subsequent intramolecular nucleophilic aromatic substitutions (SNAr) produce the enantiopure tricycles. The two step procedure represents new methodology for the stereoselective syntheses of tetrahydronaphthyridines.

Recent Advances in Protein Tyrosine Phosphatase 1B Targeted Drug Discovery for Type II Diabetes and Obesity.

Protein tyrosine phosphatase 1B (PTP1B) is an important therapeutic target for type II diabetes and obesity because of its pivotal role as a negative modulator in both insulin and leptin signalling pathways. The discovery of PTP1B inhibitors has been the focus of researchers in both academia and pharmaceutical industry over the last two decades. Though, intense pharmaceutical research in this area has resulted in many potent PTP1B inhibitors, a vast majority of them possessed pTyr mimetic group such as phosphonates, carboxylic acids and sulphamic acids, which led to poor PTP1B selectivity and insufficient in vivo efficacy due to low cell permeability and bioavailability. The availability of X-ray crystallographic structures of PTP1B together with the application of molecular modelling and other innovative strategies led to the development of many potent and selective PTP1B inhibitors with desirable physicochemical properties. This review traces the development of PTP1B inhibitors over the last decade and also records novel PTP1B inhibitors developed recently with greater emphasis on their selectivity and cell permeability.