Showing papers on "Benzoic acid published in 1988"
TL;DR: In this paper, the photooxidation rate of 22 organic solutes over a UV illuminated film of Degussa P25 titanium dioxide was studied over a 100-fold concentration range for each solute, generally from about 1 to 100 mg liter−1.
476 citations
TL;DR: Esters of N,N-disubstituted glycolamides are suggested to be a useful biolabile prodrug type for several carboxylic acid agents because they combine a high susceptibility to undergo enzymatic hydrolysis in plasma with a high stability in aqueous solution.
263 citations
TL;DR: Two types of aromatic amides, terephthalic monoanilides and (arylcarboxamido)benzoic acids, have been shown to possess potent retinoidal activities and can be classified as retinoids.
Abstract: Two types of aromatic amides, terephthalic monoanilides and (arylcarboxamido)benzoic acids, have been shown to possess potent retinoidal activities and can be classified as retinoids. The structure-activity relationships of these amides are discussed on the basis of differentiation-inducing activity on human promyelocytic leukemia cells HL-60. In generic formula 4 (X = NHCO or CONH), the necessary factors to elicit the retinoidal activities are a medium-sized alkyl group (isopropyl, tert-butyl, etc.) at the meta position and a carboxyl group at the para position of the other benzene ring. The bonding of the amide structure can be reversed, this moiety apparently having the role of locating the two benzene rings at suitable positions with respect to each other. Substitution at the ring position ortho to the amide group or N-methylation of the amide group caused loss of activity, presumably owing to the resultant change of conformation. It is clear that the mutual orientation of the benzylic methyl group(s) and the carboxyl group and their distance apart are essential factors determining the retinoidal activity. Among the synthesized compounds, 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carbamoyl]benz oic acid (Am80) and 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carboxamido] benzoic acid (Am580) were several times more active than retinoic acid in the assay. They are structurally related to retinoic acid, as is clear from the biological activity of the hybrid compounds (M2 and R2).
261 citations
TL;DR: Inhibition by salicylic acid was inversely dependent on the pH of the culture medium and did not require a continuous external supply of salicylate, compared to known inhibitors of the ethylene forming enzyme, cobalt, n-propyl gallate, and dinitrophenol.
Abstract: Salicylic acid inhibited ethylene formation from ACC in self-buffered (pH 3.8) pear (Pyrus communis) cell suspension cultures with a K(1) (app) of about 10 micromolar after 1 to 3 hours incubation. Inhibition appeared noncompetitive. Among 22 related phenolic compounds tested, only acetylsalicylic acid showed similar levels of inhibition. Inhibition by salicylic acid was inversely dependent on the pH of the culture medium and did not require a continuous external supply of salicylate. When compared to known inhibitors of the ethylene forming enzyme, cobalt, n-propyl gallate, and dinitrophenol, inhibition by salicylic acid most closely resembled that by dinitrophenol but salicylic acid did not produce the same degree of respiratory stimulation. Results are discussed in terms of other known effects of salicylic acid on plants, pH-dependency, and the possible influence of salicylic acid on electron transport.
261 citations
TL;DR: The kinetic properties of the enzyme match the kinetics of substrate uptake by whole cells and confirm a role for benzoate-CoA ligase in maintaining entry of Benzoate into cells as well as in catalyzing the first step in the anaerobic degradation of benzoates by R. palustris.
Abstract: A soluble benzoate-coenzyme A (CoA) ligase was purified from the phototrophic bacterium Rhodopseudomonas palustris. Synthesis of the enzyme was induced when cells were grown anaerobically in light with benzoate as the sole carbon source. Purification by chromatography successively on hydroxylapatite, phenyl-Sepharose, and hydroxylapatite yielded an electrophoretically homogeneous enzyme preparation with a specific activity of 25 mumol/min per mg of protein and a molecular weight of 60,000. The purified enzyme was insensitive to oxygen and catalyzed the Mg2+ ATP-dependent formation of acyl-CoA from carboxylate and free reduced CoA, with high specificity for benzoate and 2-fluorobenzoate. Apparent Km values of 0.6 to 2 microM for benzoate, 2 to 3 microM for ATP, and 90 to 120 microM for reduced CoA were determined. The reaction product, benzoyl-CoA, was an effective inhibitor of the ligase reaction. The kinetic properties of the enzyme match the kinetics of substrate uptake by whole cells and confirm a role for benzoate-CoA ligase in maintaining entry of benzoate into cells as well as in catalyzing the first step in the anaerobic degradation of benzoate by R. palustris. Images
130 citations
TL;DR: The results show that a major effect of benzoic acid on yeasts in the presence of an energy source is the energy requirement for the reduction in cytoplasmic benzoate concentration and maintenance of pH, which is unavailable for growth, resulting in lower growth yields and rates.
Abstract: Yeasts grown in the presence of benzoic acid tolerated 40 to 100% higher benzoic acid concentrations than did those grown in the absence of weak-acid-type preservatives. They also accumulated less benzoate in the presence of glucose. In chemostat cultures, benzoic acid reduced growth yield and the rate of cell production but increased specific fermentation rates. Benzoate contents were lower than those required for equilibrium when cells were impermeable to benzoate anion. Intracellular pHs were maintained near neutrality. Between species, stimulation of fermentation was inversely related to preservation resistance but was unrelated to the maximum rate of fermentation. The results show that a major effect of benzoic acid on yeasts in the presence of an energy source is the energy requirement for the reduction in cytoplasmic benzoate concentration and maintenance of pH. This energy source is unavailable for growth, resulting in lower growth yields and rates. Resistant species may be less permeable to undissociated benzoic acid.
119 citations
TL;DR: This study confirms the immaturity of the benzoic acid detoxification process in premature newborns and indicates that hippuric acid formation is deficient in preterm neonates.
Abstract: Reports on fatal benzyl alcohol poisoning in premature neonates implied that the toxicity may be due to larger doses per kilogram than for adults. It has been postulated that the load of benzoic acid (metabolite of benzyl alcohol) may exceed the capacity of the immature liver or kidney for detoxification through glycine conjugation to form hippuric acid. To test this hypothesis, 14 term and 9 preterm neonates receiving loading doses of phenobarbital containing benzyl alcohol were studied. Urine and serum benzoic and hippuric acid levels were measured by GC and HPLC methods, respectively. There was greater accumulation of benzoic acid in the serum of preterm compared to the term neonates which was reflected in higher normalized peak levels (2130.6 vs. 237.8 kg/l, p less than 0.001) and larger normalized AUCIV (1,253.2 vs. 483.0 kg.h/l, p less than 0.01). Furthermore, larger percentages of benzyl alcohol doses were found in urine as benzoic acid in preterm babies, while less hippuric acid appeared in their urine than term newborns. These results indicate that hippuric acid formation is deficient in preterm neonates. Although we did not encounter in our patients the specific toxic signs described as part of the benzyl alcohol toxicity syndrome, we cannot directly answer the issue of safety of 'low doses' of benzyl alcohol as found in some medications administered to neonates. This study confirms the immaturity of the benzoic acid detoxification process in premature newborns.
73 citations
TL;DR: One mutant lacking active muconate-lactonizing enzyme, the parent strain of which was identified as belonging to the genus Arthrobacter, was isolated and found to be capable of producing cis, cis-muconic acid with a quantitative yield of 44.1 g/l over 48 h in a 30 1 jar fermentor.
Abstract: The authors isolated numerous microorganisms with the capacity to assimilate large amounts of benzoate from many soil samples. Several of them were selected and subjected to mutation mainly by ultraviolet irradiation. One mutant lacking active muconate-lactonizing enzyme, the parent strain of which was identified as belonging to the genus Arthrobacter, was isolated and found to be capable of producing cis, cis-muconic acid with a quantitative yield of 44.1 g/l over 48 h in a 30 1 jar fermentor by successive feeding of small amounts of benzoate. This mutant, however, was more sensitive to high concentrations of the substrate than the parent strain. As few intermediates and isomers other than cis, cis-muconic acid were accumulated in the large fermentor, a large amount of pure cis, cis-muconic acid was easily obtained from the broth by salting out and recrystallization at a high recovery rate.
72 citations
TL;DR: The preliminary plasma concentration-time and urinary excretion rate-time profiles of hippuric acid and benzoic acid from a healthy subject receiving small, medium and large doses of sodium benzoate are reported.
54 citations
TL;DR: The superacid solvent trifluoromethanesulphonic acid (H 0 = − 14.6) promotes rapid polycondensation of certain aromatic dicarboxylic acids with aromatic diethers at ambient temperature, to give linear polyketones of high molecular weight.
51 citations
TL;DR: In this article, the influence of different catalysts (Pt/Al2O3, WO3 and V2O5) on the oxidation of benzoic acid adsorbed on alumina was investigated in a pulse reactor.
TL;DR: A series of highly efficient luminescence materials, benzoic acid-terbium complexes, were investigated by absorption, infrared, fluorescence and time-resolved fluorescence spectroscopy as discussed by the authors.
TL;DR: Water has a significant influence on the thermal decomposition pattern of di- n -butylphthalate (DBP) in the temperature range from 305 ° up to 390 °C and bomb water densities of up to 0.31 g cm −3 as discussed by the authors.
TL;DR: These d Dianthramides appeared during the elicitation of carnation as compounds of less importance compared with the amounts of the known dianthalexin and dianTHramides A and B.
TL;DR: Two bacterial isolates capable of growing with aniline, phenol as well as benzoate as the sole carbon and energy source were studied with respect to their taxonomic position and the enzyme reactions which initiate catabolism of the respective aromatic compounds.
Abstract: Two bacterial isolates (i.e. strains An 117 and An 213) capable of growing with aniline, phenol as well as benzoate as the sole carbon and energy source were studied with respect to (i) their taxonomic position, (ii) the enzyme reactions which initiate catabolism of the respective aromatic compounds, and (iii) the general type of regulation of the respective enzymes.
Both isolates were established to be representatives of the actinomycete-genus Rhodococcus. Experiments with resting cells and cell-free extracts, respectively, revealed that in the two strains under study catabolism of each of the unsubstituted aromatic compounds occurs via the β-ketoadipate pathway (with catechol as the central metabolite) due to the action of inducible enzymes. Although being potent inducers of the ring-cleaving catechol 1,2-dioxygenase in strains An 117 and An 213, all of the monochlorinated derivatives of aniline, phenol and benzoate, respectively, failed to support cell growth of the organisms. Cis, cis-muconic acid proved to be non-metabolizable by resting An 117 and An 213 cells, although substantial (inducible) muconate cycloisomerase activity was detectable in crude extracts prepared from the respective cell preparations. NADPH-depending phenol hydroxylase activity could be demonstrated in crude extracts from phenol-grown An 117 and An 213 cells. Evidence is presented that in both Rhodococcus strains under study substantial de novo synthesis of at least the initial aromatics-oxygenating enzymes can be induced by phenol and aniline, respectively, even in the presence of either succinate (An 117) or acetate (An 213) which are known to be ortho-pathway catabolites.
Patent•
20 May 1988
TL;DR: A process for the preparation of 5-acylamino-2,4,6-triiodo or tribromo-benzoic acid derivatives of formula (I), wherein X is I or Br, R is H or a variously substituted alkyl, or a group of formula, wherein X has the above meanings; Y is hydroxy, alkoxy, hydroxyalkoxy, alkylamino or hydroxyalkylamino; Z may be the same as COY or it is hydrooxyalkylaminocarbonyl provided that at least one
Abstract: A process for the preparation of 5-acylamino-2,4,6-triiodo or tribromo-benzoic acid derivatives of formula (I), wherein X is I or Br, R is H or a variously substituted alkyl, or a group of formula (II), wherein X has the above meanings; Y is hydroxy, alkoxy, hydroxyalkoxy, alkylamino or hydroxyalkylamino; Z may be the same as COY or it is hydroxyalkylaminocarbonyl provided that at least one of the two acyl or R groups is hydroxy-substituted, which process comprises the rearrangement of the corresponding 5-(alkylaminocarbonyl-alkoxy)-2,4,6-triiodo or tribromo-benzoic acid derivatives, in the presence of bases.
TL;DR: It is speculated that the failure to characterize chiral inversion of 2-arylpropionates in subcellular preparations may be due to the absence of a microenvironment of adequately moderate polarity.
Abstract: 1. Enrichment in the (S)-enantiomers for (R)-flurbiprofen, (R)-naproxen, (R)-suprofen and (R;S)-ibuprofen was investigated in various subcellular hepatic preparations containing coenzyme A. While such preparations were able to form hippuric acid from benzoic acid, the chiral inversion was never seen. 2. Using 2-dimethylaminoethanethiol 2-phenylpropionate (DEPP) as a model acyl thioester, the acidity of the methine proton was investigated by monitoring the proton/deuterium exchange occurring in deuterated solvents using high-resolution n.m.r. The compound was inert up to 22 h in D2O at 37 degrees C and pD 7.4. In pure methanol or a methanol-water mixture, only solvolysis was seen. In contrast, competitive hydrolysis (k = 0.005 h-1) and proton/deuterium exchange (k = 0.09 h-1) were seen in a CD3CN/D2O (50:50) mixture at 37 degrees C. 3. It is speculated that the failure to characterize chiral inversion of 2-arylpropionates in subcellular preparations may be due to the absence of a microenvironment of adequately moderate polarity.
Patent•
22 Dec 1988
TL;DR: In this article, the authors define nonaqueous sunscreen oils having a high SPF value and containing a volatile oil such as a volatile silicone oil, an emollient containing esters of straight and branched chain C 10 -C 16 alcohols and C 4 -C 20 mono- or dicarboxylic acids such as tridecyl stearate and an ester of a straight or branches-chain C 10-C 16 Alcohols.
Abstract: Non-aqueous sunscreen oils having a high SPF value and containing a volatile oil such as a volatile silicone oil, an emollient containing esters of straight and branched chain C 10 -C 16 alcohols and C 4 -C 20 mono- or dicarboxylic acids such as tridecyl stearate and an ester of a straight or branched-chain C 10 -C 16 alcohol and a tri(loweralkyl) substituted benzoic acid such as tridecyl trimellitate, esters of branched-chain C 5 -C 10 glycols and C 4 -C 20 mono- and dicarboxylic acid such as the diester of neopentyl glycol and decanoic acid and the diester of neopentyl glycol and octanoic acid and a sunscreening effective amount of at least two UV-B type sunscreens and at least one UV-A type sunscreen.
TL;DR: A range of thermophilicBacilli screened for the ability to grow on aromatic compounds were screened, and five out of ten of those studied were able to utilize aromatic acids as a sole carbon source.
Abstract: A range of thermophilicBacilli were screened for the ability to grow on aromatic compounds. Five out of ten of those studied were able to utilize aromatic acids as a sole carbon source. OtherBacilli were purified after enrichment on aromatic compounds. One of these isolates, a strain ofBacillus stearothermophilus, degraded both phenol and benzoic acid. Phenol degradation proceeded via catechol, and thereafter by oxidative and nonoxidativemeta-cleavage routes. The catalytic properties of cell-free extracts displaying the activities of the initial oxygenases have been described.
TL;DR: The mineralization of benzoic acid, phenol, and benzylamine was determined as a function of depth in two 20m sandy soil profiles, one of which was adjacent to a leach field receiving wastewater from a laundromat as mentioned in this paper.
Abstract: The mineralization of benzoic acid, phenol, and benzylamine was determined as a function of depth in two 20-m sandy soil profiles, one of which was adjacent to a leach field receiving wastewater from a laundromat. Soil samples were collected aseptically, adjusted to 20–25% water content and amended with a trace level (50 ng/g soil) of the 14C-ring-labeled compounds. Evolution of CO2 was followed with time. First-order rate constants and the extents of mineralization were estimated from the resulting data by nonlinear regression. All three compounds were mineralized in every sample examined without a lag period. In general, phenol was mineralized more rapidly than benzoic acid, which was more rapidly mineralized than benzylamine. Benzylamine had the highest sorption coefficient; phenol had the lowest. Average half-life was 0.56 days for phenol, 0.84 days for benzoic acid, and 1.31 days for benzylamine. Mineralization rates did not correlate with bacterial number, fluorescein diacetate hydrolysis rate, or a...
TL;DR: In this article, the authors investigated the kinetics of the esterification and the alcoholysis reactions and found that carboxylic acid is the only catalysts present in the reaction medium.
Abstract: Monofunctional compounds (benzoic acid, heptyl alcohol, and 2-butoxy-ethanol) were used to investigate the kinetics of the esterification and the alcoholysis reactions. Carboxylic acids (benzoic acid) are the only catalysts present in the reaction medium. The factors which influence the kinetics of the esterification reaction were studied: the nature of the carboxylic acid (substituents on the benzene ring), the nature of the alcohol, the composition of the reaction medium (alcohol alone or with another solvent, ester, or water). The results point out for an acyl type (AAC2) mechanism. The alcoholysis reaction needs the presence of carboxylic acid as a catalyst to occur significantly. A similar mechanism is proposed for both reactions: nucleophilic attack by the oxygen atom of the alcohol at the ion pair formed by protonation of the acid (esterification reaction) or by protonation of the ester (alcoholysis).
TL;DR: The results indicate that cytotoxicity of 6-O-palmitoyl ascorbic acid is attributed at least partly to both hydrogen peroxide (H2O2) and superoxide (O2-.) generated at the early stage.
TL;DR: In this article, a new reagent 2-(trifluoromethylsulfonyloxy)pyridine (TFOP) was prepared by the reaction of sodium salt of 2-pyridinol with trifluorsulfocal chloride in dioxane, which has been found to intermolecularly dehydrate from benzoic acid and aromatic hydrocarbons to give the corresponding benzophenones.
Abstract: A new reagent 2-(trifluoromethylsulfonyloxy)pyridine (TFOP) was prepared by the reaction of sodium salt of 2-pyridinol with trifluoromethylsulfonyl chloride in dioxane. The compound TFOP in trifluoroacetic acid has been found to intermolecularly dehydrate from benzoic acid and aromatic hydrocarbons to give the corresponding benzophenones in high yield. It was further elucidated, in the reaction of fluorene, that a variety of carboxylic acids can be used as the acyl precursor for the aromatic ketone synthesis in conjunction with the TFOP/TFA system. This acylation procedure has been applied to the synthesis of 2-acylthiophenes, which are hard to prepare in a satisfactory yield by the classical Friedel–Crafts reaction using aluminum chloride as the catalyst.
TL;DR: In this paper, the authors measured the effect of humic acid on the mineralization of low concentrations of [7- 14 C]benzylamine, [U-ring- 14 benzoic acid, and phenylacetic acid.
Abstract: The mineralization of low concentrations of [7- 14 C]benzylamine, [U-ring- 14 benzoic acid and [7- 14 C]phenylacetic acid was measured in the presence of 0, 5, 100 and 200 μg of humic acid ml − Humic acid increased or decreased the acclimation period and the subsequent rate of benzylamme mineralization, the effect varying with cell density and the concentrations of substrate and humic acid. Radiation-sterilized humic acid (100 μg ml − ) did not affect growth of a benzylamine-degrading bacterium. Equilibrium adsorption of benzylamine by humic acid increased with increasing concentration of amine in solution. After an 8-day equilibration period, 4–16% of the amine remained bound to the humic acid following extensive dialysis. As the percentage of binding increased, the extent of microbial mineralization of benzylamine was reduced. Benzoic and phenylacetic acids were not adsorbed by humic acid. The influence of humic acid on the acclimation period and the rate and extent of the subsequent mineralization of benzoic and phenylacetic acids varied with cell density and substrate concentration. These findings indicate that humic acid can influence mineralization of low concentrations of organic compounds by adsorbing or binding the organic substrates. The effects of humic acid on mineralization depend on the substrate.
TL;DR: A series of new allyl and vinyl carbonates has been prepared by the reaction of allyl chloroformates with 4-hydroxyphenyl esters of p -substituted benzoic acid, under phase-transfer catalysis conditions.
TL;DR: The immobilized enzyme was used in a packed bed reactor for the continuous production of d-mandelonitrile from benzaldehyde and cyanide and high concentrations of benzoic acid were shown to decrease the operational stability of the system.
Abstract: The enzyme mandelonitrile lyase was covalently immobilized on solid support materials using different methods. Immobilization on porous silica using coupling with glutaraldehyde afforded preparations with high enzyme loading (up to 9% (w/w)). The immobilized enzyme was used in a packed bed reactor for the continuous production of d-mandelonitrile from benzaldehyde and cyanide. The influence of the flow rate, pH, substrate concentrations and enzyme loading on the reaction yield and the enantiomeric purity of the product was investigated. In order to suppress the competing spontaneous reaction, the enzymatic reaction must be rapid. A flow rate of 9.5 ml/min (0.1 M benzaldehyde and 0.3 M HCN) through a 3 ml reactor afforded a 86% yield of mandelonitrile with 92% enantiomeric excess. No leakage of enzyme occurred under continuous operation. One column was used continuously for 200 h without any decrease in yield or enantiomeric purity of the product. High concentrations of benzoic acid were shown to decrease the operational stability of the system.
TL;DR: In this paper, the incorporation of 13 C-labeled thioester was established by 13 C NMR, and aqueous Tween 80 was found to have a significant effect on the degree of incorporation of the labelled compound through the leaf wax.