Liquid scintillation counting of C14 -labeled amino acids on paper, using trinitrobenzene-1-sulfonic acid, and an improved combustion apparatus.
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Amino Acids↗
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Novel functional biodegradable polymer: synthesis and anticoagulant activity of poly(gamma-glutamic acid)sulfonate (gamma-PGA-sulfonate).
gamma-Poly(glutamic acid) (gamma-PGA), which is produced by Bacillus subtilis, was sulfonated using 2-aminoethane-1-sulfonic acid (taurine) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (WSC) to give sulfonated gamma-PGA (gamma-PGA-sulfonate). From (1)H NMR spectroscopy and IR spectroscopy, it was confirmed that taurine was introduced to the side chain of gamma-PGA via an amide linkage. By altering the synthetic conditions, it was possible to control the content of sulfonate in gamma-PGA-sulfonate. Anticoagulant activity was investigated in order to evaluate the biological activity of gamma-PGA-sulfonate by the Lee-White test. The clotting time was prolonged when the concentration of gamma-PGA-sulfonate on the degree of sulfonation was increased. It becomes clear that gamma-PGA-sulfonate is potentially useful for various medical applications, such as drug delivery, tissue engineering, and medical materials.
Anticoagulants↗
Use of solid-phase extraction, reverse osmosis and vacuum distillation for recovery of aromatic sulfonic acids from aquatic environment followed by their determination using liquid chromatography-electrospray ionization tandem mass spectrometry.
Three different sample preparation techniques (i) solid-phase extraction, (ii) reverse osmosis and (iii) vacuum distillation have been investigated and the recoveries were compared for determination of highly water-soluble benzene and stilbene sulfonic acids in aqueous environment by liquid chromatography with photodiode array (PDA) and electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). The recoveries were quite high using vacuum distillation (>90%) compared to solid phase extraction and reverse osmosis. The negative ion ESI mass spectra containing the peaks of quasimolecular ion [M-H]- allow the molecular mass determination of unknown compounds whereas the structures were proposed using fragments obtained from MS/MS analysis of [M-H]- ions. At lower fragmentation voltages only the quasimolecular ion [M-H]- was observed and as fragmentation voltages increased, it led to the formation of fragment ions corresponding to [M-H-SO3]-, [M-H-SO2]-, and SO3-. The detection limits were 1-28 microg/L with LC-ESI-MS. The sample collected from wastewater treatment plant was found to contain 21.1, 13.3, 12.1, 41.8 and 9.9 microg/L of cis-4,4(l)-diaminostilbene-2,2(l)-disulfonic acid (cis-DASDA), trans-4,4(l)-diaminostilbene-2,2(l)-disulfonic acid (trans-DASDA), 3-amino acetanilide-4-sulfonic acid (3-AASA), 4-chloroaniline-2-sulfonic acid (4-CASA), 2-chloroaniline-5-sulfonic acid (2-CASA), respectively.
Chromatography, High Pressure Liquid↗
Effects of a 1.94% sulfonic acid teat dip and a 1% iodophor teat dip on teat canal infections in lactating dairy cows.
Sixty-three cows were used in a natural exposure trial for 1 yr to determine the effects of a 1.94% linear dodecyl benzene sulfonic acid and a 1% iodophor teat dip on teat canal and intramammary infections. Overall, total teat canal infections increased 28.9% and total intramammary infections increased 30% in quarters dipped with the linear dodecyl benzene sulfonic acid compared with a 14.3% increase in teat canal infections and a 17.4% decrease in intramammary infections for the iodophor group. Higher frequencies were observed for teat canal and intramammary infections caused by Staphylococcus epidermidis in the linear dodecyl benzene sulfonic acid group. Staphylococcus hyicus was the predominant organism isolated from teat canal and intramammary infections in the iodophor group. No difference was observed between the two teat dips in the persistence of Staphylococcus aureus teat canal infections. A greater number of S. hyicus teat canal infections persisted in the iodophor group, whereas teat canal infections produced by S. epidermidis and Staphylococcus xylosus persisted longer in the sulfonic acid group. Results of this study indicated that use of a linear dodecyl benzene sulfonic acid teat dip for 1 yr was not associated with increased S. aureus teat canal infections and intramammary infections. However, linear dodecyl benzene sulfonic acid appeared to affect the distribution of coagulase-negative staphylococci isolated from teat canal infections and intramammary infections.
Administration, Topical↗
Gas chromatography/mass spectrometric analysis of methyl esters of N,N-dialkylaminoethane-2-sulfonic acids for verification of the Chemical Weapons Convention.
This paper describes the synthesis and gas chromatography/electron ionization mass spectrometric (GC/EI-MS) analysis of methyl esters of N,N-dialkylaminoethane-2-sulfonic acids (DAESAs). These sulfonic acids are important environmental signatures of nerve agent VX and its toxic analogues, hence GC/EI-MS analysis of their methyl esters is of paramount importance for verification of the Chemical Weapons Convention. DAESAs were prepared by condensation of 2-bromoethane sulfonic acid with dialkylamines, and by condensation of dialkylaminoethyl chloride with sodium bisulfite. GC/EI-MS analysis of methyl esters of DAESAs yielded mass spectra; based on these spectra, generalized fragmentation routes are proposed that rationalize most of the characteristic ions.
Alkanesulfonic Acids↗
Penicillanic acid sulfone: nature of irreversible inactivation of RTEM beta-lactamase from Escherichia coli.
When penicillanic acid sulfone in large molar excess is incubated with the RTEM beta-lactamase, the enzyme becomes inactivated irreversibly. From studies of the consequential spectroscopic changes, from the use of specifically tritiated penicillanic acid sulfone, and from comparison by isoelectric focusing of the enzyme after inactivation by the sulfone and by clavulanic acid, the inactivated enzyme appears to be cross-linked by a beta-aminoacrylate fragment deriving from C-5, C-6, and C-7 of the original beta-lactam. Model studies on the behavior of alcoholic solutions of penicillanic acid sulfone in the presence of amines are entirely consistent with this interpretation.
Chemical Phenomena↗
Negative fast atom bombardment ionization of aromatic sulfonic acids: unusual sample-matrix interaction.
The most intense ion(s) in negative ion fast atom bombardment (FAB) mass spectra of 2- and 4-benzaldehyde sulfonic acid (BSA) in glycerol or 3-nitrobenzyl alcohol matrix corresponds to a covalent association of the analyte with one or two matrix molecules accompanied by the elimination of a molecule of water. The molecular ion [M - H](-), however, is of low abundance. The identity of the resulting ions [M + nA - H(2)O - H](-) (where M is the analyte and A is the matrix) was confirmed by exact mass measurement using the peak matching technique. These covalent matrix-analyte complexes were not observed when the sulfonic acid functionality in BSA was substituted with COOH, NO(2), and OH or when the sulfonic acid was in salt form. These observations indicate that the free sulfonic acid group in BSA is responsible for the covalent adduct formation. To our knowledge, analyte-matrix covalent association in negative ion FAB spectra of BSA has not been reported previously.
Benzaldehydes↗
Sulfosalicylic acid as a substitute for paratoluene sulfonic acid. A. In the estimation of cholesterol. B. In the diagnostic test for systemic lupus erythematosus.
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Benzenesulfonates↗
[Autoanalysis of amino acids with 2,4,6-trinitrobenzene-1-sulfonic acid].
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Amino Acids↗
Self-organization of polybases neutralized with mesogenic wedge-shaped sulfonic acid molecules: an approach toward supramolecular cylinders.
Complexes consisting of poly(4-vinylpyridine) and mesogenic wedge-shaped ligands 4'-[3",4",5"-tris(dodecyloxy)benzoyloxy]azobenzene-4-sulfonic acid and 4'-[3",4",5"-tris(octyloxy)benzoyloxy]azobenzene-4-sulfonic acid have been prepared with different monomer/ligand ratios. Upon protonation of the poly(4-vinylpyridine) chains by the wedge-shaped sulfonic acid molecules a hypsochromic and hyperchromic effect was observed with the pi-pi* transition of the azo-chromophor, allowing us to monitor the neutralization process by means of UV-vis spectroscopy in solution. The changes of the absorption characteristics implied a conformational change of the polymer backbone. In the bulk the interaction between pyridine and sulfonic acid moieties was proved by FT-IR spectroscopy. Polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction measurements were used to study the bulk structure of the complexes. The complexes formed a liquid crystalline lamellar phase at low degrees of substitution, while a hexagonal columnar mesophase was observed at degrees of neutralization of 80% and higher.
Journal Article↗
A new strategy for the synthesis of taurine derivatives using the 'safety-catch' principle for the protection of sulfonic acids.
The safety-catch principle has been applied for the development of a new method for protecting sulfonic acids. 2,2-Dimethylsuccinic acid was reduced to 2,2-dimethylbutane-1,4-diol, which was selectively silylated to give 4-(tert-butyldiphenylsilanyloxy)-2,2-dimethylbutan-1-ol. Reaction of the latter compound with 2-chloroethanesulfonyl chloride in the presence of triethylamine afforded 4-(tert-butyldiphenylsilyloxy)-2,2-dimethylbutyl ethenesulfonate directly. The ethenesulfonate underwent Michael-type addition with secondary amines to give protected derivatives of taurine (2-aminoethanesulfonic acid). Deprotection was achieved on treatment with tetrabutylammonium fluoride, whereby cleavage of the silicon-oxygen bond led to an intermediate alkoxide that immediately cyclised to 2,2-dimethyltetrahydrofuran with liberation of a sulfonate. Pure sulfonic acids were obtained from the crude product by ion exchange chromatography on a strongly basic resin, which was eluted with aqueous acetic acid. The method developed should be generally applicable to the protection of sulfonic acids and is amenable to a multiparallel format.
Molecular Structure↗
The effect of temperature and chloride ions on the stimulation of [3H]flunitrazepam binding by the muscimol analogues THIP and piperidine-4-sulfonic acid.
THIP and piperidine-4-sulfonic acid (PSA) interact with [3H]GABA binding sites and have GABAmimetic efficacy in vivo, but fail to enhance benzodiazepine receptor binding performed at 0 degree C. However, when [3H]flunitrazepam binding is determined at elevated temperature (30 or 37 degrees C), THIP and PSA display potent chloride ion-dependent stimulatory effects. These results resolve apparent discrepancies between the properties of GABA receptors observed in vivo and in vitro, and they suggest that the modulation of benzodiazepine receptor binding investigated at physiological temperatures can be used as an experimental system for the characterization of GABA receptors.
Animals↗
Colon epithelial cellular protein induces oral tolerance in the experimental model of colitis by trinitrobenzene sulfonic acid.
Rectal administration of trinitrobenzene sulfonic acid (TNBS) produces chronic colitis in experimental animals. However, the role of epithelial cellular protein(s) in this model is unknown. We examined whether oral tolerance can be induced in this model with colon epithelial cell proteins and whether it is organ specific. Rats were fed five times with extracts of LS-180 human colon cancer cells or HT 1080 human fibroblast cells. Syngeneic normal rat colon or small intestinal extracts were fed to separate groups of rats. After oral feedings, each rat received TNBS by enema. Rats were killed 15 days later, and the following were measured: gross and histologic disease score, weight, thickness, and myeloperoxidase values of colon and serum interferon-gamma (IFN-gamma) and transforming growth factor-beta (TGF-beta) levels. Rectal TNBS alone produced severe colitis with a 26% mortality rate. Rats fed LS-180 or rat colon extract before TNBS enema were protected, as evidenced by reductions in mortality rate, disease scores, and myeloperoxidase values. However, rats fed HT 1080 or small intestine extract lacked such protection. To examine the possible mechanism of the oral tolerance, T lymphocytes from mesenteric lymph nodes and spleen of LS-180 extract-fed rats were passively transferred to naive rats, and this was followed by TNBS enema. These rats showed clear protection. Protected animals had low IFN-gamma and high TGF-beta levels. This study demonstrates that cellular protein(s) from human colon epithelial cells, but not from human fibroblasts, can induce oral tolerance in experimental colitis. This oral tolerance is mediated by primed mesenteric and splenic T lymphocytes.
Administration, Oral↗
Freeze-drying of oxyhemoglobin: protection against oxidation in the presence of EDTA salts, sulfonic acid buffers, and pantothenic acid derivatives.
Hemoglobin was freeze-dried in the presence of salts of EDTA, sulfonic acids used as buffers, or derivatives of pantothenic acid. At 0.25 M most of the compounds effectively inhibited the formation of methemoglobin. The various model compounds used (sodium zinc EDTA, tris(hydroxymethyl) methylaminopropanesulfonic acid, and DL-pantothenol) produced similar decreases in methemoglobin formation as a function of the concentration of protective agent between 0.01 and 0.20 M. Experiments on the storage of the freeze-dried materials revealed substantial denaturation of oxyhemoglobin after 12 months at 4 degrees C. On the whole, these compounds were less effective than amino acid salts, during both desiccation and storage. The multiplicity of compounds that inhibit the denaturation of hemoglobin during freeze-drying indicates that their mode of action is nonspecific.
Buffers↗
Fluorescence of 1,8-anilinonaphthalene sulfonic acid bound to proteins and to lipids of sarcolemma.
Relative contributions to fluorescnece of 1,8-anilinonaphthalene sulfonic acid-sarcolemma by 1,8-anilinonaphthalene sulfonic acid bound to proteins and to lipid were assessed on the basis of fluorescence lifetime and steady-state emission spectra. The lifetime spectrum of lipid-poor proteins prepared from sarcolemma had a major time constant of 16 ns; that of lipids extracted from sarcolemma had a major time constant of 7 ns and a minor one of 4 ns. In sarcolemma, components having all three time constants were observed with weighting factors 0.33, 0.6 and 0.07, respectively, indicating the fraction of 1,8-anilinonaphthalene sulfonic acid bound to protein and to lipid. Steady-state emission spectra of 1,8-anilinonaphthalene sulfonic acid-sarcolemma were resolved into and resynthesized from contributions by 1,8-anilinonaphthalene sulfonic acid bound to proteins and to lipids. The latter was at least two thirds of total 1,8-anilinonaphthalene sulfonic acid bound. Results of analyses of spectra obtained with various concentrations of sarcolemma and 1,8-anilinonaphthalene sulfonic acid suggest that the proteins have a higher affinity, but only about half the binding capacity for 1,8-anilinonaphthalene sulfonic acid as do lipids.
Anilino Naphthalenesulfonates↗
Formation of pi, tau-dimethylhistidine on alkylation of trypsin with active-site-directed sulfonic acid methyl esters.
The possibility of synthesizing stable alkyl analogues of acyl trypsins by introducing the alkyl residue by means of active-site-directed sulfonic acid esters was studied. Nine amidino- or guanidino-substituted sulfonic acids of different geometries and their methyl esters were prepared. The time-dependent inhibition of bovine trypsin by these esters, indicating modification at the active site of the enzyme, was followed. With the exception of p-guanidinobenzenesulfonic acid methyl ester, all the esters acted as irreversible inhibitors. The site of methylation, Ser-195 or His-57 (chymotrypsinogen numbering), was determine by analyzing for O-methylserine and methylhistidines. With four of the esters indications of a possible formation of, at most, 0.1 residue of O-methylserine per inactivated trypsin molecule were obtained. tau-Methylhistidine (but no pi-methylhistidine) was, however, always observed as the main product of the modification reaction. A further product, hitherto not yet described in active site methylations of serine proteinases, was pi, tau-dimethylhistidine (1,3-dimethylhistidine). The failure of an attempted synthesis of the N-acetyl-ethanolamine ester of p-toluene-sulfonic acid reported in the literature is shown to be due to the high instability of this ester.
Amino Acids↗
Synthesis, surface characterization, and platelet reactivity evaluation for the self-assembled monolayer of alkanethiol with sulfonic acid functionality.
Owing to the capability of fabricating a well-defined chemical structure on the surface, self-assembled alkanethiols with a variety of terminal functionalities were prepared on the gold substrate for investigating the interactions between the biological environment and synthetic surface. In this study, we report the synthesis of the sulfonic acid terminated long-chain alkanethiol, 10-mercaptodecane-sulfonic acid, for direct preparation of a self-assembled monolayer (SAM) with -SO(3)H functionality. Nuclear magnetic resonance (NMR) and elemental analysis studies indicated that a high purity of sulfonic acid terminated alkanethiol was obtained. Surface characterization results showed that the -SO(3)H terminated SAM is hydrophilic and has a slightly higher hysteresis value, possibly because of the slower chain mobility of the bound sulfonic acid alkanethiol. Electron spectroscopy for chemical analysis (ESCA) analysis demonstrated that the -SO(3)H terminal group is situated in the outermost layer of the monolayer, as previous alkanethiol SAM structure models proposed. The platelet reactivity of the -SO(3)H SAM was higher than that of -OH SAM but less than the -CH(3) terminated one in vitro, whereas similar platelet reactivity was noticed between the -SO(3)H and -COOH SAMs. The higher platelet reactivity found on the -SO(3)H SAM could be caused by the higher surface functional group density inherent in the SAM structure and/or the composition and conformation state of the adsorbed protein layer.
Alkanesulfonic Acids↗
Chemistry of aminoiminomethanesulfinic and -sulfonic acids related to the toxicity of thioureas.
The reactions of aminoiminomethanesulfonic acid, phenylaminoiminomethanesulfonic acid, and N,N'-diphenylaminoiminomethanesulfonic acid in aqueous media at pH 7.4, 10, and 13-14 were investigated. At neutral pH hydrolysis to the corresponding urea was the major pathway for all three compounds. At higher pH phenylaminoiminomethanesulfonic acid reacted to give phenylcyanamide in nearly quantitative yield, while N,N'-diphenylaminoiminomethanesulfonic acid gave diphenylcarbodiimide which reacted further to give N,N'-diphenylurea. At pH 10 aminoiminomethanesulfonic acid reacted with itself, eventually giving N-cyanoguanidine, while at pH 13-14, elimination to cyanamide predominated. The reactions of glycine with the aminoiminomethanesulfonic acids gave guanylated acetic acids as products. The rates of these nucleophilic substitutions of the sulfonic acid group of the aminoiminomethanesulfonic acids by the amino group of glycine decreased in the order aminoiminomethanesulfonic acid greater than phenylaminoiminomethanesulfonic acid greater than (2-methylphenyl)aminoiminomethanesulfonic acid greater than (2,6-dimethylphenyl)aminoiminomethanesulfonic acid. Higher relative rates of substitution of the aminoiminomethanesulfonic acids appear to be related to higher relative toxicities for the corresponding thioureas.
Amines↗