Carboxylic acid and sulfonic acid derivatives of chalcone and chalcone epoxide [(author's transl)].
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Carboxylic Acids↗
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Aminoalkane sulfonic acids. Synthesis of some mitodepressive heterocyclic aminoalkane sulfonic acids.
The reaction of 2-aminopyrimidine with benzaldehyde in all applied methods yielded instead of benzal-2-aminopyrimidine (1) regardless of the procedure used, N.N'-benzilidene-bis-2-aminopyrimidine (2). The expected product benzal-2-aminopyrimidine has not been formed in any case. For this reason the synthesis of aminoalkanesulfonic acids has not been carried out by the use of Schiff bases as starting material. Reaction of aldehyde bisulfite adducts and corresponding amine, was used instead. In the syntheses where 2-aminopyridine was used as the amine part, the corresponding aminoalkanesulfonic acids were formed (3--5), while 2-aminopyrimidine under the same condition gave several reaction products (6--10). All compounds obtained were tested for their growth inhibitory activity on the seeds of cress (Lepidium sativum L.).
Aminopyridines↗
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↗
Suppressor cells for the afferent phase of contact sensitivity to picryl chloride: inhibition of DNA synthesis induced by T cells from mice injected with picryl sulfonic acid.
Previous reports have shown that picryl sulfonic acid (PSA) induces suppressor T cells that inhibit the effector phase of contact sensitivity, whereeas its DNP counterpart, dinitrobenzenesulfonate (DNBS) induces cells that inhibit the afferent phase of sensitization. Accordingly, cells from mice injected with DNBS, but not PSA, could be shown to inhibit the DNA synthesis in the lymph nodes that occurs during sensitization. It is now shown that PSA does induce T cells that suppress DNA synthesis but this can only be detected with enriched T cells or by using a regimen of PSA injection different frm previously used to induce suppressor cells for the effector phase. The T cells did not affect responses to oxazolone or dinitrofluorobenzene (DNFB) and were distinguishable from suppressors of the efferent phase in that they could be produced in adult thymectomized but not cyclophosphamide-treated mice. T cells from mice injected with DNBS that inhibited DNA synthesis to DNFB had the same properties.
Animals↗
Anion transport in red blood cells. I. Chemical properties of anion recognition sites as revealed by structure-activity relationships of aromatic sulfonic acids.
The present study is concerned with the chemical factors that determine the inhibitory properties of reversible aromatic sulfonic acids on sulfate exchange system of human red blood cells. Two series of compounds were tested for inhibitory potencies: benzene sulfonic acid (BS) and 2,2'-disulfonic stilbene (DS) derivatives, each series with substituent groups such as Cl, OH, NH2, NO2, NNN, N-acetamido, and N-benzoamido. As judged by various kinetic criteria, all congeners of BS and DS appear to have common sites of action in the anion transport system. The range of inhibitory potencies, as defined by the concentration required to produce 50% inhibition (ID50), varied over a 10(4) range (ID50:2-50,000 microM). The degree of inhibition was correlated with two physicochemical properties of the substituent groups: (a) lipophilicity, as judged by the pi values (Hansch factor) of the groups; and (b) the electronic character, as judged by sigma values (Hammett factor) of the groups. Optimal correlations were obtained with a linear combination of the two factors. Based on the above structure-activity relationships and on a comparison between the inhibitory properties of congeners of BS and DS, we suggest that the microenvironment of substrate recognition sites bears a positive multipolar character and possesses functionally essential groups with electron donor capacity embedded in a hydrophobic area.
Anions↗
Passive cation movements in the Ehrlich ascites tumor cell: the effects of 2,4,6-trinitrobenzene sulfonic acid.
We have investigated the effects of 2,4,6-trinitrobenzene sulfonic acid (TNBS), an amino reactive reagent, on passive cation movements in Ehrlich ascites tumor cells. Incubation of tumor cells with TNBS (3 mM) results in a two phase association of TNBS with the cells. An initial, rapid phase, presumably at the level of the membrane, is independent of temperature, while the second phase increases linearly in time and is temperature dependent. Kinetic analyses of Na+ movements indicate that TNBS: (1) inhibits Na+ movement from a slowly exchanging cellular compartment, but is without effect on a more rapidly exchanging compartment; (2) does not alter net Na+ accumulation in transport-inhibited cells; and (3) is without effect on non-exchange Na+ efflux at 0 degrees C. The actions of TNBS on K+ movements depend upon temperature and the continued presence of TNBS in the environment. At 22 degrees C two minute exposure of the cells to TNBS leads to 77% inhibition of K+ efflux. With continued exposure to TNBS, the inhibition is only 42%. Reduction of the temperature to 0 degrees C decreases K+ efflux in control cells by 82%. Two minute exposure to TNBS enhances K+ efflux by 50%, while continuous exposure increases it by 144%. These results suggest: (1) TNBS interacts with several classes of membrane sites which are involved with the regulation of passive cation movements; and (2) passive Na+ and K+ movements across the cell membrane proceed by different pathways.
Biological Transport↗
[Specific modification of free lysine amino groups of histidine decarboxylase from Micrococcus sp. n. by trinitrobenzene sulfonic acid].
It has been found that 14 lysine residues are accessible for trinitrobenzene sulfonic acid (TNBS) in the molecule of histidine decarboxylase (HDC). The other 62 lysine residues in the molecule of native HDC are masked and inaccessible for TNBS. It is demonstrated that the SH- and alpha-amino groups of methionine are not modified by TNBS. A correlation between the decarboxylase activity of the enzyme and the degree of its trinitrophenylation has been studied. HDC, whose molecule contains 3--9 TNP groups, retains up to 90--97% of its initial activity. Trinitrophenylation of 14 lysine residues induces inactivation of HDC by 33--34%, which probably depends on conformational changes or steric hindrances, occurring in the catalytic site of the modified active centre of HDC. Using circular dichroism and fluorescence methods as well as disc-electrophoresis in polyacrylamide gel, it has been shown that trinitrophenylation does not cause any significant changes in the enzyme structure. The TNP groups have been found to be localized in the large and small subunits of the HDC molecule.
Carboxy-Lyases↗
Determination of free and esterified cholesterol by a kinetic method. I. The introduction of the enzymatic method with 2,2'-azino-di-3[ethyl-benzthiazolin sulfonic acid (6)] (ABTS).
A new, simple kinetic method is described for the determination of serum cholesterol based on the oxidation of 2,2'-azino-di-3[ethyl-benzthiazolin sulfonic acid (6)] (ABTS) by use of a single aqueous reagent. This assay procedure is rapid, specific, reproducible and applicable to the measurement of free and esterified cholesterol in a continuous procedure. The method requires no prior treatment of sample and linear kinetics are obtained up to 13 mmol/l cholesterol. The use of ABTS permits the direct calculation of cholesterol concentrations from absorbance changes at 410 nm (A = epsilon - c - d).
Benzothiazoles↗
On the properties of solid and liquid ion exchangers. II. Infrared and NMR studies of lithium and cesium salts of dinonylnaphtalene sulfonic acid in heptane.
Infrared and NMR measurements on solutions of lithium and cesium dinonylnaphtalene sulfonates (DNNS-salts) in heptane show that the state of water in these systems is in several respects similar to its state in solid ion exchange resins and in some respects also similar to that in ordinary water. The two cations differ in their interaction with the sulfonic acid group at low water contents, the interaction being stronger for Li+. Spin-lattice relaxation measurements on LiDNNS show that the state of lithium both in DNNS and in solid resins is quite different from that of lithium salts in aqueous solutions of the corresponding concentration.
Chromatography, High Pressure Liquid↗
Re-evaluation of turbidimetry of proteins by use of aromatic sulfonic acids and chloroacetic acids.
From studies on 11 different proteins (including native albumin and albumin with reduced disulfide-bridges) treated with sulfosalicylic, 2-naphthalenesulfonic, toluenesulfonic, dichloroacetic, or trichloroacetic acids, we elucidate the interactions determining the resulting turbidities and other factors affecting turbidities, and we discuss the clinical utility of such turbidimetry. At least three interactions are important in determining turbidity: reduction of positive charges on the protein, hydrogen bonding of the non-ionized chloroacetic acids with the protein, and hydrophobic interaction of the aromatic sulfonic acids with albumin. Turbidity varies appreciably with the species of acid and protein, concentrations of acid, temperature, and standing time after acid is added. We conclude that this technique should be restricted to confirming proteinuria.
Albumins↗
Centrifugal analyzer method for total bilirubin in serum by use of diazotized 2-chloroaniline-5-sulfonic acid.
We describe two centrifugal analyzer methods for measuring total bilirubin in serum. Diazotized 2-chloroaniline-5-sulfonic acid is used in both. In the first procedure, ethylene glycol and methanol are used as an accelerator solvent; results correlate well with those by a Jendrassik and Grof method adapted to the centrifugal analyzer, but there is considerable hemolysis interference. In the second method, dimethyl sulfoxide is used with the ethylene glycol/methanol solvent and almost all hemolysis interference is eliminated. For either method, a 15-microliter sample is required. In the second method, instrument response is linearly related to concentration to 250 mg/L and the within-run precision (CV) is about 1%.
Azo Compounds↗
[The reaction of heteroaromatic N-oxide with acid chloride and cyanide. VI. On the reaction of isoquinoline 2-oxides with sulfonic acid chloride and potassium cyanide (author's transl)].
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Chemical Phenomena↗
A study of the effects of p-chloromercuribenzene sulfonic acid on acetylcholine-induced responses of molluscan neurons.
The effects of the organic mercurial p-chloromercuribenzene sulfonic acid (PCMBS) on the acetylcholine receptors of two types of neurons from the marine gastropod Anisodoris nobilis were studied. Cell types were distinguished by the ion-specific conductance change resulting from applied cholinergic agents: in certain cells a conductance increase to Cl resulted (Cl-neurons); in other cells a cation conductance increase resulted (D cells). Exposure of the Cl-neurons to 1 mM PCMBS at 4 degrees C had two distinct effects: 1) the sensitivity of the membrane conductance to microelectrophoretically applied carbamylcholine was blocked in a few minutes; and 2) the membrane conductance slowly increased with an inversion potential which was the same as that of the cholinergically induced response. d-Turbocurarine did not appreciably reduce this conductance increase. However, applying carbamylcholine during the exposure period to PCMBS reduced the PCMBS response. The cholinergic response of D cells was affected to a much lesser degree by PCMBS.
4-Chloromercuribenzenesulfonate↗
[The reaction of heteroaromatic N-oxide with acid chloride and cyanide. VII. On the reaction of pyridine 1-oxides with sulfonic acid chloride and potassium cyanide (author's transl)].
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Chemical Phenomena↗
On the mechanism of divalent metal ion chelator induced activation of the 7S nerve growth factor esteropeptidase. Activation by 2,2',2''-terpyridine and by 8-hydroxyquinoline 5-sulfonic acid.
Our previous studies (Pattison, S. E., and Dunn, M. F. (1975), Biochemistry 14, 2733) have shown that the reaction of divalent metal ion chelators with the 140 000 mol wt mouse submaxillary nerve growth factor protein (7S NGF) activates the iota-subunit esteropeptidase activity ca. sevenfold. Ultraviolet-visible spectral studies with the chelator 2,2',2''-terpyridine (terpyridine) and fluorescence emission studies with 8-hydroxyquinoline-5-sulfonic acid (HQSA) in combination with both conventional and rapid-mixing stopped-flow kinetic techniques have been employed in the present study to investigate (a) the mechanism of the chelator-induced activation process, and (b) the identity of the divalent metal ion involved. The spectral studies confirm the presence of stoichiometrically significant amounts of tightly bound zinc ion in native 7S NGF (1-2 g-atoms of An2+/mol of 7S NGF). The kinetic studies show that the reaction of terpyridine with 7S NGF occurs via a two-step process involving first a rapid, apparent second-order step (k1 = 1 x 10(6) M-1 s-1) to form a 7S NGF-Zn2+-chelator monocomplex, then a slow step to form a bis(terpyridine)-Zn(II) complex and activated 7S NGF in an apparent first-order process (kobsd = 0.10 min-1). This rate is, within experimental error, identical with the apparent first-order rate constant for the chelator-induced activation process (monitored by the rate of change in the steady-state rate of hydrolysis of chromophoric substrate, alpha-N-benzoyl-D,L-arginine-p-nitroanilide). Kinetic studies of the reaction of HQSA with native 7S NGF show that, under the same conditions of concentration, the rate of formation of the tris(HQSA)-Zn(II) complex is identical with the rate of the HQSA-induced activation of the 7S NGF esteropeptidase. Thus, these studies unambiguously establish that zinc ion is the metal ion involved in the chelator-induced activation process, and that activation involves removal of zinc ion from native 7S NGF.
Animals↗
Anion transport in red blood cells. II. Kinetics of reversible inhibition by nitroaromatic sulfonic acids.
The anion exchange system of human red blood cells is highly inhibited and specifically labeled by isothiocyano derivatives of benzene sulfonate (BS) or stilbene disulfonate (DS). To learn about the site of action of these irreversibly binding probes we studied the mechanism of inhibition of anion exchange by the reversibly binding analogs p-nitrobenzene sulfonic acid (pNBS) and 4,4'-dinitrostilbene-disulfonic acid (DNDS). In the absence of inhibitor, the self-exchange flux of sulfate (pH 7.4, 25 degrees C) at high substrate concentration displayed self-inhibitory properties, indicating the existence of two anion binding sites: one a high-affinity transport site and the other a low-affinity modifier site whose occupancy by anions results in a noncompetitive inhibition of transport. The maximal sulfate exchange flux per unit area was JA = (0.69 +/- 0.11) X 10(-10) moles . min-1 . cm-2 and the Michaelis-Menten constants were for the transport site KS = 41 +/- 14 mM and for the modifier site Ks' = 653 +/- 242 mM. The addition to cells of either pNBS at millimolar concentrations or DNDS at micromolar concentrations led to reversible inhibition of sulfate exchange (pH 7.4, 25 degrees C). The relationship between inhibitor concentration and fractional inhibition was linear over the full range of pNBS or DNDS concentrations (Hill coefficient n approximately equal to 1), indicating a single site of inhibition for the two probes. The kinetics of sulfate exchange in the presence of either inhibitor was compatible with that of competitive inhibition. Using various analytical techniques it was possible to determine that the sulfate transport site was the target for the action of the inhibitors. The inhibitory constants (Ki) for the transport sites were 0.45 +/- 0.10 microM for DNDS and 0.21 +/- 0.07 mM for pNBS. From the similarities between reversibly and irreversibly binding BS and DS inhibitors in structures, chemical properties, modus operandi, stoichiometry of interaction with inhibitory sites, and relative inhibitory potencies, we concluded that the anion transport sites are also the sites of inhibition and of labeling of covalent binding analogs of BS and DS.
Anions↗
[The reaction of heteroaromatic N-oxide with acid chloride and cyanide. III. On the reaction of quinoline N-oxides with sulfonic acid chloride and potassium cyanide (author's transl)].
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Chemical Phenomena↗
Temperature effects on 1,8-anilinonaphthalene sulfonic acid fluorescence with sarcolemma vesicles.
Increased temperature produces a red shift and decreased fluorescence intensity of the emission peak of 1,8-anilinonaphthalene sulfonic acid (ANS) in suspensions of biomembrane vesicles. These changes have been attributed to a conjectured increase in polarity of the microenvironment of ANS. If the conjecture is correct, fluorescence lifetimes must be decreased with warming. We showed than ANS binds to both protein and lipid protein of sarcolemma, that there are two kinds of sarcolemma-lipid ANS-binding sites, and that there are three fluorescence lifetimes of excited sarcolemma-bound ANS. The three fluroescence lifetimes were unchanged on warming, or decreased too little to account for the observations. Fluorescence lifetime data were consistent with the notion that the effect of increasing temperature is to decrease the amount of ANS bound to sarcolemma. From studies of liposomes prepared from lipid extracts of sarcolemma, and of proteins from sarcolemma it was deduced that warming reducted the amount of ANS bound to both of these sarcolemma components, probably mainly by reducing binding capacity. There might also be a shift of affinities such that the ratio, KA sarcolemma lipid/KA sarcolemma protein, is larger at higher temperature. Except at very small concentration ratios of ANS/sarcolemma, more than twice as much ANS was bound to sarcolemma lipids as to proteins.
Anilino Naphthalenesulfonates↗