Showing papers on "Benzoic acid published in 1976"

Galloylglucoses of low molecular weight as mordant in electron microscopy. II. The moiety and functional groups possibly involved in the mordanting effect.

Abstract: Synthetic pentamonogalloylglucose applied to fixed tissues acts as a mordant, inducing high and diversified contrast similar to that obtained with natural gallotannins of low molecular weight (LMGG). By the separate use of each of the two moieties of the galloylglucose molecule, it was found that gallic acid is the mordanting agent. Glucose may contribute, however, to the effect by increasing the solubility and cross-linking potential of the compound, since the mordanting induced by gallic acid alone is weaker than that produced by its hexose esters. As suggested by results obtained with various phenolics and benzoic acid derivatives, the functional groups required for the mordanting effect of such agents are the carboxyl group, and at least one hydroxyl group concomitantly present on the benzene ring. In the case of galloylglucoses, it is assumed that the effect is due to hydrolysis products (gallic, digallic, or trigallic acids) or to the multiple hydroxyl groups of the intact molecule. Esters of gallic acid (propyl- and methylgallate), as well as pyrogallol, produce a "reversed staining" of all membranes, except for those of communicating (gap) junctions.

[Degradation of 4-chlorobenzoic acid by an Arthrobacter species (author's transl)].

Abstract: An Arthrobacter sp. growing on 4-Chlorobenzoic acid as its sole source of carbon excretes 4-hydroxygenzoic acid and protocatechuic acid into the culture medium. Protocatechuic acid is further attacked by "meta"-cleavage. During growth of the Arthrobacter sp. on benzoic acid cis-cis muconic acid can be isolated from the medium, suggesting the involvement of the "ortho"-cleavage pathway. The enzymes both for the "meta"- and the "ortho"-cleavage pathway are inducible.

The development of new iron-chelating drugs.

Abstract: 2,3-Dihydroxybenzoic acid has been identified as a potentially useful iron-chelating drug. Accordingly, we have evaluated a series of derivatives of hydroxylated benzoic acids for their ability to induce iron excretion in the iron-overloaded rat. In addition, we have examined a number of hydroxamic acids and some other naturally occurring iron-chelating agents. Of the 26 benzoic acid derivatives studied, none appeared to be more effective than 2,3-dihydroxybenzoic acid, for reasons which are discussed. Rhodotorulic acid, a hydroxamic acid produced by and isolated from cultures of Rhodotorula pilimanae, was the most effective of all the compounds studied in inducing iron excretion. When administered parenterally, rholotorulic acid induced iron excretion via both the urinary and the fecal routes and was more than twice as potent (on a weight basis) as desferrioxamine. Two ferrous chelators, alpha, alpha-dipyridyl ad 1,10-phenanthroline, induced a moderate amount of iron excretion, suggesting that a pool of ferrous iron may be available for chelation.

Purification and properties of an enzyme catalyzing the splitting of carbon-mercury linkages from mercury-resistant Pseudomonas K-62 strain. I. Splitting enzyme 1.

Abstract: An enzyme (S-1) which catalyzes the splitting of carbon-mercury linkages of organomercury compounds was purified about 24-fold from the cell-free extract of mercury-resistant Pseudomonas K-62 strain by treatment with streptomycin, precipitation with ammonium sulfate, and successive chromatography on Sephadex G-150, DEAE-Sephadex, and DEAE-cellulose. A purified preparation of the enzyme showed a single band on polyacrylamide gel electrophoresis, and was colorless. The molecular weight of the enzyme was estimated to be 19,000, and Km was 5.3 X 10(-5) M for p-chloromercuribenzoic acid (PCMB). The temperature and pH optimum for the reaction were 50degrees and 7.0, respectively. The enzyme was capable of catalyzing the decomposition of methylmercuric chloride (MMC), ethylmercuric chloride (EMC), phenylmercuric acetate (PMA), and PCMB in the presence of a sulfhydryl compound to form a mercuric ion plus methane, ethane, benzene, or benzoic acid, respectively. The mercuric ion thus formed was reduced to metallic mercury by metallic mercury-releasing enzyme (MMR-enzyme).

Reaction pathways of in vivo stereoselective conversion of ethylbenzene to (-)-mandelic acid.

Abstract: 1. Mandelic acid formed in vivo from ethylbenzene as well as from various oxidation intermediates was laevo mandelic acid and was of surprisingly high optical purity.2. Reaction sequences are proposed for the stepwise oxidation of ethylbenzene to mandelic acid.3. Although the initial hydroxylation of ethylbenzene to methylphenyl-carbinol is stereoselective, the optical activity of mandelic acid is not established at this point since the optical centre is destroyed in the second step, dehydrogena-tion to acetopheneone.4. Acetophenone appears to be a precursor of not only mandelic acid and benzoylformic acid but benzoic acid as well.5. The route from acetophenone involves conversion to eu-hydroxyaceto-phenone and subsequent reduction to glycol and/or oxidation to phenylglyoxal.6. The configuration of mandelic acid is determined either during reduction of hydroxyacetophenone or reduction of phenylglyoxal.

Metabolism of o-phthalic acid by different gram-negative and gram-positive soil bacteria

Abstract: Different bacteria, isolated from soil by the enrichment method, were able to grow on phthalic acid as carbon source. Protocatechuate was identified as intermediate in phthalate metabolism. All phthalategrown bacteria oxidized phthalate and protocatechuate rapidly without having a lag-period. Benzoic acid, terephthalic acid, protocatechuic acid, salicylic acid, di- and mono-butyl phthalate were also metabolized by some of the organisms, benzoic acid being degraded via catechol and terephthalic acid via protocatechuate as intermediate. All organisms tested cleaved protocatechuate or catechol, respectively, by the “ortho” fission, when grown on phthalate, terephthalate, or benzoate as carbon source. A characterization and tentative identification of the organisms is given.

Ionic mechanism of the salicylate block of nerve conduction.

Abstract: Benzoic acid, salicylic acid and 5-bromosalicylic acid have been studied for their mechanism of action on crayfish and squid giant axons. External application of 0.1 to 0.5 mM 5-bromosalicylic acid prolonged the falling phase of the action potential, and at concentrations higher than 1.5 mM, nervous conduction was blocked. Boltage clamp analyses showed that 5-bromosalicylic acid reduced both peak transient sodium conductance and steady-state potassium conductance. The curves relating the peak and steady-state conductances to membrane potential were shifted in the direction of depolarization. The time constant for the activation of sodium current (taum) was not affected by 5-bromosalicylic acid, whereas the time constant for the sodium inactivation (tauh) was greatly increased. The steady-state sodium inactivation curve (h infinity) was shifted in the hyperpolarizing direction. The rate constants alpha h and beta h were decreased. The rate of activation of potassium current was reduced. The block of peak transient conductance by externally applied 5-bromosalicylic acid was largely reversed by internal washing suggesting that the drug acts on a membrane site more easily accessible from inside than from outside. Salicylic and benzoic acids were much less potent than 5-bromosalicylic acid, reducing peak conductance by 12.5 and 3%, and steady-state conductance by 8.7 and 7%, respectively, at a concentration of 10 mM.

Iso- or terephthalic acid production in and recovery from benzoic acid-water solvent system

Abstract: This invention relates to the continuous production of iso- or terephthalic acid in a stirred reaction zone by catalytic air oxidation of m- or p-xylene in the presence of a benzoic acid-water liquid solvent system at constant gauge pressure within the range of 7 to 21 kg/cm2 wherein oxidation temperature within the range of 175° to 235° C. is maintained substantially constant by the novel control thereof by only varying the flow rate of water condensate reflux to the oxidation zone. The invention further pertains to novel means for achieving such temperature control. Also, the present invention relates to a novel continuous recovery of the phthalic acid product from the fluid effluent of said continuous process by a process wherein crystalline phthalic acid product is separated from essentially water-free benzoic acid mother liquor; the crystalline product is successively washed with liquid benzoic acid and the corresponding xylene; the washed product is dried; and the water removed from said fluid effluent, the benzoic acid and xylene wash liquors, xylene recovered from product drying, and a major proportion of the benzoic acid mother liquor are charged to the oxidation process. The invention further relates to a novel combination of apparatus for the continuous conduct of said oxidation and recovery processes.

Effects of various acids and salts on growth and aflatoxin production by Aspergillus flavus NRRL 3145.

Abstract: The effects of sodium chloride, sodium acetate, benzoic acid, sodium benzoate, malonic acid, and sodium malonate on growth and aflatoxin production by Aspergillus flavus were investigated in synthetic media. Sodium chloride at concentrations equivalent to or greater than 12 g/100 ml inhibited growth and aflatoxin production, while at 8 g or less/100 ml, growth and aflatoxin production were stimulated. At 2 g or less/100 ml, sodium acetate also stimulated growth and aflatoxin production, but reduction occurred with 4 g or more/100 ml. Malonic acid at 10, 20, 40, and 50 mM reduced growth and aflatoxin production (over 50%) while sodium malonate at similar concentrations but different pH values had the opposite effect. Benzoic acid (pH 3.9) and sodium benzoate (pH 5.0) at 0.4 g/100 ml completely inhibited growth and aflatoxin production. Examination of the effect of initial pH indicated that the extent of inhibitory action of malonic acid and sodium acetate was a function of initial pH. The inhibitory action of benzoic acid and sodium benzoate appeared to be a function of undissociated benzoic acid molecules. Aflatoxin reduction was usually accompanied by an unidentified orange pigment, while aflatoxin stimulation was accompanied by unidentified blue and green fluorescent spots but with lower Rf values that aflatoxins B1, G1, B2, and G2 standards.

Chemical transformation of S-benzyl O-ethyl phenylphosphonothiolate (Inezin) by ultraviolet light.

Abstract: The photodecomposition of Inezin (S-benzyl O-ethyl phenylphosphonothiolate) in n-hexane under the ultraviiolet irradiation was investigated by gas liquid chromatography, thin layer chromatography, mass spectrometry, and infrared spectroscopy. Two main steps of photodecomposition were observed at the initial stage of irradiation. One was the cleavage of P-S bond to produce O-ethyl phenylphosphinate and dibenzyl disulfide, the latter of which was degraded rather rapidly to produce sulfuric acid and benzoic acid through toluene-alpha-sulfonic acid by oxidation. The other step was the isomerization to the thionate, O-benzyl O-ethyl phenylphosphonothionate, which was gradually oxidized to itx oxygen analogue, O-benzyl O-ethyl phenylphosphate. O-ethyl phenylphosphinate, O-benzyl O-ethyl phenylphosphonate and O-benzyl O-ethyl phenylphosphonthionate were fairly stable under the ultraviolet light, as compared with Inezin. As hydrolysis products of the parent compound, phenylphosphonic acid, O-ethyl hydrogen phenylphosphonate, O-ethyl hydrogen phenylphosphonothioate and benzyl alcohol were detected.

Solid phase synthesis of protected peptides

Abstract: The invention is addressed to the preparation of 3-nitro-4-bromomethyl benzoic acid, as a new compound from which 3-nitro-4-bromomethyl benzoyl amide polystyrene resin can be prepared for solid synthesis of protected peptide acids and amides and separation thereof without cleavage of acid labile protecting groups or decomposition of aromatic acid groups and from which purified polypeptides can be formed.

Doubly Charged Ion Mass Spectra of Monosubstituted Aromatic Compounds

Abstract: The 2E doubly charged ion mass spectra of twelve simple monosubstituted aromatic compounds were recorded. The spectral pattern of these compounds can be classified into three types. When the substituent is strongly electron-donating such as the amino or dimethylamino group, a very intense molecular ion peak appears, no fragment ion peak being observed. Phenol, anisole, toluene, and chlorobenzene show both molecular and fragment ion peaks in varying intensities. The parent benzene itself behaves similarly. Only fragment ion peaks were observed for nitrobenzene and aromatic carbonyl compounds such as benzaldehyde, acetophenone, methyl benzoate, or benzoic acid. The major fragmentation reactions are discussed.

Liquid crystalline thio-benzoic acid derivs. for dielectrics - esp. phenyl thio-benzoates, biphenyl thio-carboxylic acid esters and diphenylyl thio-benzoates

Abstract: New thiobenzoates have formula (I):- (where R1 and R2 are 1-12C alkyl, alkoxy or alkyl mercapto, 2-12C alkanoyl, alkanoyloxy or alkoxycarbonyloxy, or one of these gps. is also -CN or -NO2. Nos. m and n are 1 or 2, provided n + m =3). (I) are either S-phenyl thiobenzoates, (Ia), biphenyl thiocarboxylic acid esters (Ib) or S-biphenylyl thiobenzoates (Ic): (I) are used as mixing components of liquid crystalline dielectrics for electro-optical indicator elements, working in twisted nematic cells or by dynamic scattering or phase deformation. (I) form, either along or with other mesomorphs, liquid-crystalline phases having m.pts. up to room temp. and clarifying points at higher temps. than known comparable mixts. An example describes prepn. of 4-n-heptyl-thiobenzoic acid-S-4-n-pentyl-phenyl ester from 4-n-heptyl benzoyl chloride and 4-n-pentyl-thiophenol.

Determination of benzoic and sorbic acids in orange juice.

Abstract: A procedure has been devised for the separate determination of benzoic and sorbic acids in orange juice. It is based on the steam distillation of these preservatives from an acidified juice into an alkaline trap. The distillate is divided into two portions, each of which is treated with potassium dichromate and sulphuric acid, but under different conditions. Drastic oxidation leads to the destruction of sorbic acid and, after re-distillation, allows the determination of benzoic acid at 225 nm (with no interference from sorbic acid). Milder oxidation selectively converts sorbic acid into malonaldehyde, and the latter is subsequently converted into a coloured compound and determined at 532 nm (with no interference from benzoic acid).Recoveries of both preservatives from orange juice were satisfactory.

Formation of benzoic acid and p-hydroxybenzoic acid in the blue green alga Anacystis nidulans: a thylakoid-bound enzyme complex analogous to the chloroplast system.

Abstract: The photosynthetic procaryote Anacystis nidulans converts L-phenylalanine and L-tyrosine into benzoic acid and p-hydroxybenzoic acid, respectively. Results obtained with thylakoid fractions support the hypothesis that the reaction sequence is catalyzed by thylakoid-bound enzyme complexes consisting of phenylalanine ammonia-lyase and benzoate synthase of tyrosine ammonia-lyase and p-hydroxybenzoate synthase, respectively. Btoh complexes do not accept phenylacetic acids as substrates, and cinnamic acids only at a small extent. These properties suggest a striking similarity to a benzoic acid-synthesizing enzyme system from higher plants which is situated at the thylakoid membrane of chloroplasts. The respective complexes of Dunaliella marina and Porphyridium sp. were included in this comparison.

Mechanismen der elektronenstoßinduzierten Methanoleliminierung aus ortho- und para-substituierten Benzoesäuremethylestern / Mechanisms of Electron Impact Induced Elimination of Methanol from ortho- and para-Substituted Benzoic Acid Methyl Ester

Abstract: Using deuterium labelled compounds the mechanisms of methyl as well as methanol elimination from the title compounds have been established. It can be shown that in the case of 4-methoxy-methyl benzoic acid methyl ester the unusual methanol elimination from the [M-methyl]+ ion probably proceeds via the formation of a π-complex and a ring expansion reaction. In addition to this novel fragmentation some ortho-effects and other fragmentation reactions useful for an analytical identification of the ortho/para-isomers by means of mass spectrometry are discussed.

Rubber compositions with benzoic acid compounds

Abstract: Rubber compositions containing relatively large amounts of benzoic acid or monohydroxy benzoic acid providing vulcanized rubber products having improved adhesion to metallic or fibrous materials and an improved chipping and cutting resistance. This is a continuation of application Ser. No. 588,047, filed June 18, 1975, now abandoned.

Thermal Studies on the Phase Transitions of p-n-Octadecyloxy Benzoic Acid (Part I)

Abstract: Thermal properties of p-n-octadecyloxybenzoic acid were investigated and the effects of the long paraffinic chain attached to the benzoic acid on the molecular motion in the mesophase are discussed. It was found that p-n-octadecyloxybenzoic acid had three crystalline forms; Crystal-I, Crystal-II and Crystal-III. Crystal-I is stable and Crystal-II and -III are metastable. It was concluded that the paraffinic chain in the Crystal-I. It is suggested that p-n-alkoxybenzoic acids in general, has physical properties of both liquid and plastic crystals.

Association Equilibria of Benzoic Acid

Abstract: The solubility of water in benzene containing benzoic acid has been measured and the concentration of the dissolved water found increasing parallel witli the acid concentration. According to these results, in benzene solutions containing water, the formation of monomer monohydrate, monomer dihydrate, dimer monohydrate and dimer dihydrate, too, have to be taken into account and their formation constants can be calculated. Considering the hydration equilibria a relation can be expressed between the apparent and the real dimerization constants.

Method of effecting antihistaminic, antiserotonin and antiallergic actions

Abstract: Antihistaminic, antiserotonin and antiallergic effects are achieved by administering to a subject requiring the same a (quinuclidyl-3)-diaryl (heteryl)carbinol of the formula: ##STR1## wherein n is 0 or 1, wherein R and R' are the same or different substituted, unsubstituted or hydrated phenyl or heteroaryl and wherein A is either absent or is a physiologically compatible acid such as hydrogen chloride, hydrogen bromide, phosphoric acid, sulphuric acid, maleic acid, adipic acid, citric acid, tartaric acid, benzoic acid, or fumaric acid.

The separation of polar and steric effects. Part XIII. Kinetics of the reactions of cinnamic acid and meta-substituted cinnamic acids with diazodiphenylmethane in various alcohols and in aprotic solvents

Abstract: Rate coefficients have been determined for the reactions at 30 °C of diazodiphenylmethane with cinnamic acid and meta-substituted cinnamic acids (substituents: Me, Cl, or NO2) in 12 alcohols, in ethyl acetate, and in acetone.The reactions of cinnamic acid with diazodiphenylmethane in alcohols show a good linear free-energy relationship with the corresponding reactions of benzoic acid. The solvent effect can be interpreted in terms of the dielectric constant and the influence of hydrogen bonding. Multiple linear correlation with three suitable solvent parameters is quite successful. Comparisons are made with the benzoic and the phenylacetic acid system.The Hammett ρ-values (ρ3) for the reactions of cinnamic acids are correlated with solvent parameters and comparisons are made with ρ-values for the benzoic (ρ1) and the phenylacetic (ρ2) acid system. The expressions ρ3= 0.39ρ1, and ρ2= 0.60 (ρ1– 0.25) hold, and are interpreted in terms of Bowden, Chapman, and Shorter's treatment of the transmission of polar effects through side-chains.

Method of retarding the growth of plants using certain oxadiazolyl, oxazolyl or thiadiazolyl benzoic acid derivatives

Abstract: Plant growth regulant effects, such as dwarfing, cessation of terminal growth, increased flower set, increased fruit and pod set, fruiting body abortion, twisting and epinastic responses, etc., may be accomplished on crops such as soybeans, cotton, etc., by application of certain 2-(1,3,4-oxadiazol-2-yl) or 2-(2-oxazolyl) or 2-(1,3,4-thiadiazol-2-yl)benzoic acids, salts and esters, having the formula ##STR1## where X is nitrogen or C--R" (R" being hydrogen or methyl), Z is oxygen or sulfur when X is nitrogen, Z is oxygen and when X is C--R", R is phenyl or various substituents, and R' is hydrogen or various substituents. An example is 2-(5-phenyl-1,3,4-oxadiazol-2-yl)benzoic acid. The compounds where X is nitrogen and Z is sulfur are new compounds, e.g., 2-(5-phenyl-1,3,4-thiadiazol-2-yl)benzoic acid.

l‐Glutamate Dehydrogenase. Enhancement of the Reactivity of the p‐Chloromercuribenzoate‐Binding Site in Presence of the Competitive Label Methyl Mercuric Chloride

Abstract: Modification of l-glutamate dehydrogenase with p-chloromercuribenzoate leads to the incorporation of one molecule per subunit of enzyme. Correlation between spectrophotometric measurements and p-chloromercuri[carboxyl-14C]benzoic acid binding argues for the formation of one cysteinylmeteurial bond. Kinetic studies indicate that the slow reactivity of the -SH group is due to an inherent property of the enzyme. In presence of methylmercuric chloride, there is a big decrease of the labelling of the enzyme by p-chloromercuribenzoic acid. However kinetic studies demonstrate the existence of a ternary complex enzyme-p-chloromercuribenzoate-methylmercuric chloride which is characterized by a high p-chloromercuribenzoic acid dissociation rate constant. The possible significance with respect to the protein structure is discussed.