Synthetic Sulfonate Research Articles

ANTICORROSIVE PROPERTIES OF SULFONATE ADDITIVES

The article is devoted to the study of the anticorrosive properties of sulfonate additives mixed with HC4
 hydrocracking base oil. The results of a study of the anticorrosive effectiveness of sulfonate additives NSSK-30, S-150,
 SSK-400 are presented. The patterns of changes in the protective properties of synthetic sulfonate additives depending
 on the value of their alkaline number have been revealed. A qualitative and quantitative assessment of the effectiveness
 of using sulfonate additives in a mixture with HC4 base oil as inhibitory compounds to protect steel from corrosion
 under the action of an electrolyte, in a climatic chamber and a salt mist chamber was carried out. It has been shown
 that the effectiveness of the protective action of inhibitory compounds increases with a decrease in the alkaline number
 of the sulfonate additive. The nature of the change in the surface of steel plates in the process of their corrosion
 destruction, accompanied by the formation of pitting, is revealed.

Metahemoglobinemia inducida por dapsona: reporte de un caso en el servicio de urgencia

Methemoglobinemia is a low prevalence but potentially severe condition in the Emergency Department. One of its leading causes is drug induction, dapsone being one of them. Dapsone is a synthetic sulfone with antimicrobial properties, often prescribed for prophylaxis against Pneumocystis jiroveci infection and other implications. This report presents the case of a 39-year-old male recently diagnosed with HIV on antiretroviral therapy along with prophylactic dapsone, who sought medical attention in the emergency room due to symptoms of cough, dyspnea, and fever. On admission, the patient exhibited a state of tachypnea and an oxygen saturation of 78% in room air, which is partially corrected with supplemental oxygen at an inspired oxygen fraction of 50%, achieving oxygen saturation of 90% by pulse oximetry. Chest X-ray revealed no abnormalities, and arterial blood gas analysis showed a partial pressure of oxygen of 380 mmHg with oxygen saturation of 100%. Given the disparity between pulse oximetry, arterial blood gas results, and the normal chest X-ray, a co-oximetry was conducted, revealing a methemoglobin level of 10.4% The patient was admitted to the ICU and continued receiving oxygen therapy. Dapsone was discontinued and the patient’s condition improved. without the need for methylene blue administration or alternative therapies.

Impact on methemoglobin and certain oxidative stress markers in diabetic and non-diabetic Hansen’s disease patients with dapsone treatment

Introduction: Hansen’s (leprosy) disease is a worldwide healthcare problem, caused by Mycobacterium leprae. Dapsone (a synthetic sulfone), is an antibacterial agent, has both anti-inflammatory and immunomodulatory properties for the treatment of all forms of leprosy. The goal of the study is to evaluate the effect of dapsone on HbA1C, methemoglobin and certain oxidative stress markers in young patients suffering with Hansen’s disease with and without diabetes.
 
 Methodology: The study was conducted on 70 subjects in age group of 20-45 years. These subjects include 20 healthy subjects (Group 1); 35 non-diabetic Hansen’s patients on dapsone (100mg/day) treatment (Group 2) and 15 diabetic Hansen’s disease on dapsone (100 mg/day) (Group 3). The fasting blood samples were drawn for the evaluation of methemoglobin, HbA1C, malondialdehyde, reduced glutathione and total antioxidant activity from all the groups.
 
 Results: A significant increase in methemoglobin and malondialdehyde was noted in Group 2 and 3 patients with reference to healthy control subjects (Group 1) while the levels of reduced glutathione, HbA1C and total antioxidant activity were notably reduced in investigated Group 2 and 3 compared to Group 1. A similar trend of significant increase in methemoglobin and malondialdehyde levels in Group 3 with respect to Group 2 and significant fall in glutathione and total antioxidant activity and nominal fall in HbA1C was recorded in Group 3 with respect to Group 2.
 
 Conclusion: Aforesaid observations suggested that oxidative stress induced in diabetic and non-diabetic Hansen’s disease patients treated with dapsone due to alteration in Met. Hb, MDA, reduced glutathione and total antioxidant activity levels might be accountable for the etiology of various diseases like cancer, arthritis, and cardiovascular events. A comprehensive study with clinical trials inclusive of complete oxidative stress markers, antioxidant enzymes, pattern of dietary intake with antioxidant vitamin supplements alone and in combination might be beneficial.

Dapsone for Refractory Gastrointestinal Symptoms in Children With Immunoglobulin A Vasculitis.

Immunoglobulin A vasculitis (IgAV) is a systemic small-vessel vasculitis. Although corticosteroids (CS) are the primary treatment for gastrointestinal manifestations associated with IgAV, some patients develop refractory or recurrent symptoms such as vomiting and abdominal pain despite CS treatment. Dapsone, a synthetic sulfone antimicrobial, has been used to treat cutaneous purpura in IgAV, but few authors have reported its use for refractory gastrointestinal symptoms. In this retrospective observational study, we describe results in 7 children with IgAV who were treated with dapsone for abdominal pain resistant to CS. Dapsone rapidly relieved abdominal pain in all 7 patients, who then were tapered off CS without relapse. Side effects of mild methemoglobinemia and hemolysis appeared to be manageable with planned monitoring and dose adjustment; a single patient who discontinued dapsone had fatigue and hypoxia associated with methemoglobinemia. No side effects were life-threatening. Dapsone may be considered as a therapeutic option for gastrointestinal symptoms refractory to CS in children with IgAV.

Synthetic sulfonate additives for lubricating oils

Synthetic sulfonate additives for lubricating oils

Transient effectiveness of dapsone for skin lesions in a patient with discoid lupus erythematosus

Dapsone is a synthetic sulfone preparation and is second-line treatment for cutaneous lupus erythematosus (CLE) including discoid LE (DLE). This report describes a patient with DLE, which was improved by dapsone quickly but the recurrence was noted. Oral administration of prednisolone (5 mg / day) was required but the complete healing was very difficult. In this report, we will discuss the effectiveness and limitation of dapsone for patients with DLE and the mechanisms of action.

New synthetic sulfone derivatives inhibit growth, adhesion and the leucine arylamidase APE2 gene expression of Candida albicans in vitro

The successful preventing and effective treatment of invasive Candida albicans infections required research focused on synthesis of new classes of agents and antifungal activity studies. Bromodichloromethyl-4-chloro-3-nitrophenyl sulfone (named compound 6); dichloromethyl-4-chloro-3-nitrophenyl sulfone (named 7); and chlorodibromomethyl-4-hydrazino-3-nitrophenyl sulfone (named 11) on inhibition of planktonic cells’ growth, leucine arylamidase APE2 gene expression, and adhesion to epithelial cells were investigated. In vitro anti-Candida activities were determined against wild-types, and the morphogenesis mutants: Δefg1 and Δcph1. MICs of compounds 6, 7 and 11 (concentrated at 0.25–16μg/ml) were determined using the Clinical and Laboratory Standards Institute Broth Microdilution Method (M27-A3 Document). APE2 expression was analyzed using RT-PCR; relative quantification was normalized against ACT1 in cells growth in YEPD and on Caco-2 cell line. Adherence assay of C. albicans to Caco-2 was performed in 24-well-plate.The structure activity relationship suggested that sulfone containing hydrazine function at C-1 (compound 11) showed higher antifungal activity (cell inhibition%=100 at 1–16μg/ml) than the remaining sulfones with chlorine at C-1. Δcph1/Δefg1 was highly sensitive to compound 11, while the sensitivity was reduced in Δcph1/Δefg1::EFG1 (%=100 at 16-fold higher concentration). Compound 11 significantly affected adherence to epithelium (P ⩽0.05) and hyphae formation. The APE2 up-regulation plays role in sulfones’ resistance on MAP kinase pathway. Either CPH1 or EFG1 play a role in the resistance mechanism in sulfones. The strain-dependent phenomenon is a factor in the sulfone resistance mechanism. Sulfones’ mode of action was attributed to reduced virulence arsenal in terms of adhesiveness and pathogenic potential related to the APE2 expression and morphogenesis.

Synergistic Effects of MoDTC and Overbased Calcium Sulfonate Additive

The synergetic effects of molybdenum dialkyldithiocarbamate (MoDTC) and overbased liner alkyl benzene synthetic calcium sulfonate (OBCaS) on the tribological performance of lubricant were investigated using reciprocating ball-on-disk sliding friction tester. The results showed that the two kinds of additives with a certain range of concent ration could improve tribological properties of alone MoDTC. The mass percent of 0.5% MoDTC and 2% OBCaS in pure poly-alpha-olefin (PAO) has the best friction reducing and anti-wear properties.

Determination of seven synthetic dyes in animal feeds and meat by high performance liquid chromatography with diode array and tandem mass detectors

An efficient method was developed for the simultaneous determination of seven commonly used synthetic sulfonate dyes (Ponceau 4RC, Sunset yellow, Allura red, Azophloxine, Ponceau xylidine, Erythrosine and Orange II) in animal feed and meat using high performance liquid chromatography (HPLC-DAD) and tandem mass spectrometry (HPLC–MS/MS). Ethanol–ammonia–water (80:1:19, V/V/V) solution was used as extract solution, which can extract target species while reducing interference from the sample matrices. The recoveries of these 7 dyes in animal feed and chicken meat were between 71% and 97% with relative standard deviations less than 14.8%. HPLC–MS/MS was employed as a further means of confirmation to assure accuracy of the results. Limits of detection for these dyes were in the range of 0.02–21.83ngmL−1. The proposed method can be applied to confirmative screening of seven commonly used food colorants in feed and meat samples.

Dapsone Inhibits IL-8 Secretion From Human Bronchial Epithelial Cells Stimulated With Lipopolysaccharide and Resolves Airway Inflammation in the Ferret

IL-8 is an important activator and chemoattractant for neutrophils that is produced by normal human bronchial epithelial (NHBE) cells through mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) p65 pathways. Dapsone, a synthetic sulfone, is widely used to treat chronic neutrophil dermatoses. We investigated the effects of dapsone on polarized IL-8 secretion from lipopolysaccharide (LPS)-stimulated NHBE cells and further evaluated its ability to decrease LPS-induced inflammation in the ferret airway. NHBE cells were grown at air-liquid interface (ALI) to ciliated differentiation. Baseline and endotoxin (LPS)-stimulated IL-8 secretion was measured by enzyme-linked immunosorbent assay at air and basal sides with and without dapsone. Western blotting was used to determine signaling pathways. In vivo, ferrets were exposed to intratracheal LPS over a period of 5 days. Once inflammation was established, oral or nebulized dapsone was administered for 5 days. Intraepithelial neutrophil accumulation was analyzed histologically, and mucociliary transport was measured on the excised trachea. Dapsone, 1 μg/mL, did not influence unstimulated (basal) IL-8 secretion. Apical LPS stimulation induced both apical and basolateral IL-8, but basolateral LPS increased only basolateral IL-8. Dapsone inhibited polarized IL-8 secretion from ALI-conditioned cells. Dapsone also decreased LPS-induced IL-8 mRNA level. LPS led to phosphorylation of extracellular signal-regulated kinase 1/2, but not p38 MAPK or c-Jun NH(2)-terminal kinase. LPS also induced NF-κB p65 phosphorylation, an effect that was inhibited by dapsone. Both oral and aerosol dapsone decreased LPS-induced intraepithelial neutrophil accumulation, but only treatment with aerosol dapsone restored mucociliary transport to normal. Dapsone, given either systemically or as an aerosol, may be useful in treating neutrophilic airway inflammation.

Binary and ternary inclusion complexes of dapsone in cyclodextrins and polymers: preparation, characterization and evaluation

Dapsone (DAP) is a synthetic sulfone drug with bacteriostatic activity, mainly against Mycobacterium leprae. In this study we have investigated the interactions of DAP with cyclodextrins, 2-hydroxypropyl-β-cyclodextrin (HPβCD) and β-cyclodextrin (βCD), in the presence and absence of water-soluble polymers, in order to improve its solubility and bioavailability. Solid systems DAP/HPβCD and DAP/βCD, in the presence or absence of polyvinylpyrrolidone (PVP K30) or hydroxypropyl methylcellulose (HPMC), were prepared. The binary and ternary systems were evaluated and characterized by SEM, DSC, XRD and NMR analysis as well as phase solubility assays, in order to investigate the interactions between DAP and the excipients in aqueous solution. This study revealed that inclusion complexes of DAP and cyclodextrins (HPβCD and βCD) can be produced in order to improve DAP solubility and bioavailability in the presence or absence of polymers (PVP K30 and HPMC). The more stable inclusion complex was obtained with HPβCD, and consequently HPβCD was more efficient in improving DAP solubility than βCD, and the addition of polymers had no influence on DAP solubility or on the stability of the DAP/CDs complexes.

Dapsone efficacy and adverse events in the management of mucous membrane pemphigoid

Auteur(s) : Anne M Hegarty, Martyn Ormond, Maureen Sweeney, Tim Hodgson Oral Medicine Unit UCL, Eastman Dental Institute and UCLHT Eastman Dental Hospital, 256 Gray’s Inn Road, London WC1X 8LD Dapsone is a synthetic sulfone with antimicrobial and anti-inflammatory properties. It inhibits migration and adherence of neutrophils and synthesis of prostaglandins E2 [1, 2]. By blocking neutrophil migration, dapsone may act to prevent inflammation and new vesicle formation in mucous membrane pemphigoid [...]

Dapsone 5% Gel

Dapsone, a synthetic sulfone that has been available for over 60 years, has been used to treat a myriad of cutaneous disorders. Prior to the general acceptance of isotretinoin, oral dapsone had been reported to be effective in the treatment of nodulocystic acne. However, the potential for systemic toxicity prevented its widespread adoption in the treatment of acne. For many years scientists explored the possibility of developing a topical formulation of dapsone for the treatment of acne in the hope of minimizing the adverse hematologic effects of oral dapsone. Such a formulation had been unavailable until recently. Dapsone 5% gel (Aczone) was recently developed to treat acne vulgaris. This topical formulation was approved in the US based on two randomized, vehicle-controlled studies. A 12-month, open-label study was also conducted to assess the safety and efficacy of topical dapsone over the long term. Finally, two open-label phase I pharmacokinetic studies were conducted to evaluate the systemic absorption of topical dapsone compared with oral dapsone. This article reports the results of these studies, which show a reduction in acne lesion count comparable to those observed in clinical trials of other approved topical acne therapies. With regard to safety, the studies demonstrated that the concentrations of dapsone and N-acetyl dapsone remain low and do not accumulate over time once steady state is reached. Of the total of 50 patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency in all the studies, only two experienced a drop in hemoglobin levels, and those shifts in values were consistent with fluctuations observed for other study participants. A recent study evaluating the risk of hemolysis in patients with G6PD deficiency found topical dapsone 5% gel to be safe to use in this patient population. Based on the observations noted in the above-mentioned studies, we conclude that topical dapsone 5% gel is safe and effective in the treatment of acne vulgaris.

Betaine structure and the presence of hydroxyl groups alters the effects on DNA melting temperatures

Betaine lowers the melting temperature of deoxyribonucleic acid (DNA) and decreases its dependence on base composition. The effects of synthetic betaine analogs on the melting of DNA samples with different GC content were measured. Since many polyhydroxy compounds also lower DNA melting temperatures, hydroxyl-substituted betaine analogs were included. Some synthetic sulfonate analogs of betaine lowered the DNA melting temperatures by twice as much at the same molar concentration. They were up to twice as effective at decreasing the base pair dependence. Some carboxylate homologs of betaine, substituted with hydroxyl groups, increased the melting temperature. This effect was greater with low GC content DNA. Sulfonate analogs of betaine with hydroxyl groups usually destabilize the DNA, while their carboxylate analogs stabilize the DNA. Distances between the charges of these synthetic zwitterionic solutes influence the effect on DNA, with the optimum separation being two or three methylene groups. A betaine with two hydroxyl groups on one N-alkyl group had a greater effect than an isomer with two hydroxyl groups on separate N-alkyl substituents. We suggest that the effect of these solutes depends on structuring the hydration water of DNA, as well as interactions with the DNA structure itself.

Medium-caustic sulfonate additive for motor oils. Based on alkyltetralin

Effective new additives, including sulfonate additives, are required for creating high-quality motor oils which meet the requirements of current and future technology [1]. We developed a medium-caustic synthetic sulfonate additive based on alkyltetralin.

Dapsone in rheumatoid arthritis

Dapsone, a synthetic sulfone with chemical similarities to sulfapyridine, has been used for a number of years to treat leprosy and dermatitis herpetiformis. Recently, a number of prospective, randomized, double-blind trials have shown their success in the management of rheumatoid arthritis, with dapsone being superior to placebo and comparable to chloroquine and hydroxychloroquine. Its mode of anti-inflammatory actions in rheumatoid arthritis is not clearly understood, but modulation of neutrophil activity or inhibition of neutrophil inflammatory product formation or release appear to play a role. The major limiting side effect is hemolytic anemia, which may be mitigated through careful patient selection, conservative drug dosing, close monitoring, and possibly, concurrent administration of antioxidants or cytochrome P450 inhibitors. Methemoglobinemia is another common finding among patients receiving dapsone therapy, but rarely does it result in prominent symptoms other than transient pallor. Less common adverse events to dapsone include the idiosyncratic reactions of leukopenia and agranulocytosis, cutaneous eruptions, peripheral neuropathy, psychosis, toxic hepatitis, cholestatic jaundice, nephrotic syndrome, renal papillary necrosis, severe hypoalbuminemia without proteinuria, an infectious mononucleosis-like syndrome, and minor neurological and gastrointestinal complaints. In this report, two patients with advanced rheumatoid arthritis, who were safely and effectively treated with dapsone after failure with other second-line agents, are described and the literature is reviewed. We suggest that dapsone is an effective second-line agent in the treatment of rheumatoid arthritis.

Solubilization of methanol by calcium alkylarenesulfonates in hydrocarbon media

Solubilization of methanol by the calcium salts of four different sulfonate surfactants, dinonylnaphthalenesulfonate, a synthetic sulfonate, mixed petroleum/synthetic sulfonate, and petroleum sulfonate, in hydrocarbon media has been studied by gas chromatography (GC). It was found that the calcium synthetic sulfonate had a greater ability to solubilize methanol than calcium petroleum sulfonate. Methanol solubilization appears to depend on the carrier solubility parameter. The results of a complementary NMR study on the calcium mixed synthetic/petroleum sulfonate complement of the GC findings, indicating that the solubility of methanol in the bulk carrier strongly influences the methanol solubilization by sulfonate. It was shown that the presence of CaCO{sub 3} in the polar core of the (inverted) sulfonate micelle reduces the ability of sulfonate to solubilize methanol.

Recurrent methomoglobinemia after acute dapsone intoxication in a child

Dapsone is a synthetic sulfone increasingly used in the treatment of a wide variety of dermatologic disorders. The case of a child with dapsone-induced recurrent methemoglobinemia is presented with a discussion of dapsone toxicity and its treatment. In addition, the diagnostic value of pulse oximetry in the presence of dysfunctional hemoglobins is discussed.

Surfactant Flooding With Hard Water: A Case Study Solved by HLB Gradient

Summary Surfactant formulations were designed for field application of micellar processes in a salty environment on the basis of a mixture of one synthetic sulfonate with two types of nonionic agents. This formulation led to the required Winsor-III-type phase diagram in the presence of reservoir fluids at reservoir temperature. The main difficulty in this study was the high level of surfactant retention in the reservoir rock. The sacrificial agents tested did not reduce these surfactant losses significantly. The solution found to be efficient consisted of creating a hydrophile-lipophile balance (HLB) gradient of the additives used in situ by injecting a desorbing agent with high HLB behind the micellar slug containing the nonionic cosurfactants with lower HLB. The interpretation proposed for such a procedure shows that the mechanisms involved produce the same beneficial effects as the salinity gradient technique. The good results obtained indicate the potential importance of the HLB gradient when the salinity gradient cannot be used in the micellar processes under consideration.

Kinetic Study of the Decomposition of Surfactants for EOR

Summary The effect of temperature, pH, surfactant purity, and air on the decomposition rate of two classes of surfactants typically used in steam EOR processes has been investigated. With synthetic alkylaryl sulfonates, isolation and characterization of the hydrocarbon reaction products established that the principal reaction is desulfonation of the surfactant. The kinetics of the decomposition of certain alkylaryl sulfonates under carefully controlled pH and temperature conditions are discussed and compared with the behavior observed for α-olefin sulfonates (AOS's) under the same conditions. The synthesis and decomposition of key pure isomeric alkylaromatic sulfonates of known structure led to a mechanistic description of the decomposition reaction. An explanation for the differing stability of alkylaromatic sulfonates and AOS's at high temperatures and at differing pH is suggested.