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Showing papers on "Acetic acid published in 1970"



Journal ArticleDOI
David Dolphin1
TL;DR: In this article, the reaction between pyrroles and benzaldehyde in refluxing acetic acid gives meso-tetraphenylporphins and chlorins.

122 citations


Journal ArticleDOI
TL;DR: In this article, the catalytic effect of palladium on the synthesis of vinyl acetate from ethylene has been studied, and it was shown that co-catalysts such as potassium or other alkali metals promote the abstraction of hydrogen from acetic acid and weaken palladium-oxygen bonds in dissociatively adsorbed acetic acids.

116 citations


Patent
01 May 1970
TL;DR: In this article, the authors present a survey of INDENYL ACETIC ACIDS and non-toXIC PHARMACEUTICALLY ACCEPTABLE AMIDES, ESTERS, and SALTS.
Abstract: NEW SUBSTITUTED INDENYL ACETIC ACIDS AND NONTOXIC PHARMACEUTICALLY ACCEPTABLE AMIDES, ESTERS AND SALTS DERIVED THEREFROM. THE SUBSTITUTED INDENYL ACETIC ACIDS DISCLOSED HEREIN HAVE ANTI-INFLAMMATORY, ANTI-PYRETIC AND ANALGESIC ACTIVITY. ALSO INCLUDED HEREIN ARE METHODS OF PREPARING SAID INDENYL ACETIC ACID COMPOUNDS, PHARMACEUTICAL COMPOSITIONS HAVING SAID INDENYL ACETIC ACID COMPOUNDS AS AN ACTIVE INGREDIENT AND METHODS OF TREATING FLAMMATION BY ADMINISTERING THESE PARTICULAR COMPOSITIONS TO PATIENTS.

104 citations


Journal ArticleDOI
TL;DR: In this paper, the α-and β-anomers of the β-hexopyranosides are oxidized to aoetylated methyl 4-hexulosonates.
Abstract: Fully acetylated methyl β-D-hexopyranosides are oxidized by chromium trioxide in acetic acid to acetylated methyl 5-hexulosonates. Catalytic hydrogenation of these keto esters leads into the L-series. The corresponding a-D-glycosides are not oxidized in the same way, with the exception of methyl tetra-O-acetyl-α-D-idopyranoside. Both α- and β-anomers of the acetylated fnranosides are oxidized to aoetylated methyl 4-hexulosonates. The octaacetates of α- and β-lactose are similarly oxidized, the ring of the galactose moiety being opened. The methyl pyranoside of a branched-chain sugar, with no hydrogen atom on C5, is oxidized to a 4-keto ester, acetyl migration occurring from O4 to O5.

100 citations



Journal ArticleDOI
TL;DR: The enzymic assay described in paragraphs 2–4 constitutes a method for determining the absolute configuration of asymmetric methyl groups, provided that a substantial proportion of the tritium in the specimen examined is present in such groups.
Abstract: 1 By chemical synthesis starting from phenylacetylene and utilizing stereospecific reactions, two specimens of acetic acid were prepared in which the following conditions were closely approached: (a) some of the methyl groups consisted of one hydrogen, one deuterium, and one tritium atom attached to carbon; (b) all such methyl groups in one specimen had the R configuration, and all such methyl groups in the other specimen had the S configuration, and the correct absolute configuration was assignable to each specimen from the method of synthesis used; (c) all methyl groups containing a tritium atom also contained a deuterium atom. 2 Each specimen of acetic acid was converted enzymically into acetyl-coenzyme A and (in the same incubation) this product was condensed with glyoxylic acid on malate synthase to form two specimens of S-malic acid. 3 Each specimen of malic acid was incubated with fumarase until the tritium content of the organic acids (fumarate + malate) had ceased to fall. 4 Malic acid synthesized from R-acetic acid retained 69% of its carbon-bound tritium (in fumarate + malate) on incubation with fumarase. Malic acid synthesised from S-acetic acid retained 31% of its carbon-bound tritium. 5 The enzymic assay described in paragraphs 2–4 constitutes a method for determining the absolute configuration of asymmetric methyl groups, provided that a substantial proportion of the tritium in the specimen examined is present in such groups. 6 The method thus established can be used to study the mechanism of enzymic reactions in which a methylene group is converted stereospecifically into a methyl group. With one logical proviso–that it is necessary to known whether protium or deuterium is preferentially removed by the enzyme from methyl groups also containing tritium–the method is also applicable to enzymic reactions in which a methyl group is converted stereospecifically into a methylene group. 7 Subject to the above proviso, it is indicated that on malate synthase the removal of hydrogen and the attachment of the glyoxylate residue occurs with inversion of configuration.

83 citations



Journal ArticleDOI
TL;DR: Methods of obtaining acid-soluble collagen fractions are compared and Extraction with 0·5M acetic acid at 40°C for 60 min periods is found to be the preferred method for mice skins.

58 citations



Journal ArticleDOI
TL;DR: The rates of production of volatile material from PVA, PVC and vinyl acetate-vinyl chloride copolymers, covering the entire composition range, have been compared using thermal volatilization analysis.

Journal ArticleDOI
TL;DR: In this article, the critical water concentrations required for initiating precipitation of cellulose acetate from 20% solutions in acetone, dioxane, acetic acid, triethyl phosphate (TEP), dimethyl formamide (DMF) and dimethyl sulfoxide (DMSO) have been determined.

Journal ArticleDOI
TL;DR: The gross kinetics for the oxidation of ethylene were determined over Pd and PdAu alloys in a steady-state flow reactor and in a recirculating reactor in which the products were stripped with each pass as mentioned in this paper.

Journal ArticleDOI
TL;DR: In this paper, the effect of gradually reducing the pH of pasteurized milk with acetic, citric, hydrochloric, lactic, and phosphoric acids over periods of 4, 8, and 12 hours was determined.
Abstract: The effect of gradually reducing the pH of pasteurized milk with acetic, citric, hydrochloric, lactic, and phosphoric acids over periods of 4, 8, and 12 hr on growth of Staphylococcus aureus 100 in this substrate was determined. In addition, 1: 1 mixtures of lactic acid and each of the other acids, and of acetic and citric acids were evaluated for their effect on growth of this organism. To achieve a 90% reduction in growth over a 12 hr period, a final pH value of 5.2 was required for acetic, 4.9 for lactic, 4.7 for phosphoric and citric, and 4.6 for hydrochloric acid. A 99% reduction during a 12 hr period was obtained with a final pH value of 5.0 for acetic, 4.6 for lactic, 4.5 for citric, 4.1 for phosphoric, and 4.0 for hydrochloric acid. A pH value of 3.3 was required for a 99.9% reduction with hydrochloric acid, whereas the same effect was produced at a pH value of 4.9 with acetic acid. Correspondingly lower pH values were required to inhibit growth within 8 and 4 hr periods. Mixtures of acids adjuste...

Journal ArticleDOI
TL;DR: In this article, 13 products have been isolated from degradation of d-glucose with methylamine and acetic acid and two compounds are responsible for the caramel odor observed in this degradation and have been identified as acetylformoin and 4-hydroxy-2,5dimethyl-3(2 H )-furanone.

Journal ArticleDOI
TL;DR: In this paper, the major acylating acid in acylated anthocyanin-3-monoglucosides in grapes was identified by i.r., NMR, and mass spectrometry.

Patent
14 Sep 1970
TL;DR: In this paper, substituted pyrazol-4-acetic acid compounds, such as substituted pyracic acid, its esters, amides, nitriles and their pharamaceutically acceptable salts and method for the preparation of these compounds are disclosed.
Abstract: Pyrazol-4-acetic acid compounds, such as substituted pyrazol-4-acetic acid, its esters, amides, nitriles and their pharamaceutically acceptable salts and method for the preparation of these compounds are disclosed. The novel compounds are useful analgesics, anti-inflammatory, and antipyretics.

Journal ArticleDOI
TL;DR: In this paper, a mechanism for the surface reaction of acetic acid on chromia is suggested and discussed based on a comparison of the energies of activation and the previously established fact that both the dehydration and dehydrogenation activity of chromia are required for the ketonization reaction.

Journal ArticleDOI
TL;DR: In this article, reaction between (π-C5H5)2ZrH2 and carboxylic acids can result in the formation of acylates or alkoxides depending on the mode of addition.

Journal Article
TL;DR: There was an approximately linear relationship between the extent of inactivation (expressed as lethal hits) and the frequency of mutations; the slopes of these lines were similar for all the esters studied.
Abstract: Summary Reaction of the sulfuric acid ester of N -hydroxy-4-acetylaminobiphenyl and of the acetic acid esters of N -hydroxy-4-acetylaminobiphenyl, N -hydroxy-4-acetylaminostilbene, and N -hydroxy-2-acetylaminophenanthrene with transforming DNA of Bacillus subtilis in vitro caused both inactivation of transforming activity and the induction of mutations. The parent amides, amines, N -hydroxy amides, and N -hydroxy amines each yielded little or no inactivation or mutation of the transforming DNA under similar conditions. These data are consistent with and in extension of our previous studies on the inactivation and mutation of transforming DNA by esters of N -hydroxy-2-acetylaminofluorene. The magnitude of the inactivating and mutagenic activity of the esters depended both on the nature of the esterified acid and of the aryl group. Sulfuric acid esters of N -hydroxy-2-acetylaminofluorene and N -hydroxy-4-acetylaminobiphenyl were each more active than the corresponding acetic acid esters. Under similar conditions, the acetic acid ester of N -hydroxy-2-acetylaminofluorene caused more inactivation and more mutations than did the acetic acid esters of the other 3 N -hydroxy amides. In all cases, there was an approximately linear relationship between the extent of inactivation (expressed as lethal hits) and the frequency of mutations; the slopes of these lines were similar for all the esters studied. The synthesis of N -hydroxy-2-aminophenanthrene, a new compound, is described.

Journal ArticleDOI
TL;DR: The growth of the 3T6 mouse fibroblast and synthesis of macromolecules has been studied over the last 6 days of the cultures9 14-day life span.
Abstract: The growth of the 3T6 mouse fibroblast and synthesis of macromolecules has been studied over the last 6 days of the cultures9 14-day life span. The effect of ascorbic acid was also tested. During this period, the cells synthesized collagen, as judged by the appearance of non-dialysable hydroxyproline, which was identified by chemical assay and by radioactive incorporation studies. A high proportion of the collagen in the cell layer was insoluble in 0.1 N acetic acid. Of the hydroxyproline synthesized in the presence of ascorbic acid, about 75% was eventually liberated into the growth medium, and about 25-30% of the liberated material behaved as free hydroxyproline. In the absence of ascorbic acid, the cell layer hydroxyproline was reduced to one-third, but the growth medium hydroxyproline was unaffected. The cells also synthesized glycosaminoglycans, as judged by the appearance of cetyl pyridinium-precipitable uronic acid, and the incorporation of labelled glucosamine into macro-molecules. A large proportion of this material has the properties of hyaluronic acid. Ascorbic acid had no detectable effect on overall glycosaminoglycan synthesis, in contrast to healing tendonectomy wounds in guinea-pigs. Cell proliferation and general protein synthesis were virtually unaffected by ascorbic acid. Whereas general protein synthesis, like cell proliferation, declined in the ageing culture, glycosaminoglycan synthesis and collagen synthesis continued at a steady or increasing rate.

Journal ArticleDOI
TL;DR: The extendedculture kinetic data are shown to be substantially different from continuous culture kinetic data, and reason for these differences are discussed in light of diffrences in the cell age distributions, as well as possible differences in experimental conditions.
Abstract: Extended culture, a special type of semicontinuous culture, permits prolonged maintenance of a constant or programmed environment in a growing culture by a controlled addition of one or more substrates. Differences between extended culture and continuous culture data are a measure of differences in the properties of cell populations with different cell age distributions but identical steady-state environments. Both extended culture and continuous culture were used to study the growth kinetics of Candida utilis (ATCC 9226) under conditions of substrate inhibition at controlled concentrations of sodium acetate in a carbon-limited mineral salts medium supplemented with 0.01 g/1 yeast extract. Acetate concentrations ranged from 1.2 g/l to 10.8 g/l (expressed as acetic acid), while yeast concentrations varied from 0.3 to 7.8 (g dry cells)/1. Rate parameters such as growth yields (Y), specific growth rates (μ), and linear growth rates (K), were calculated by computer from the data and theory presented herein. Specific growth rates as high as 0.54/hr were observed, although extended culture growth was more nearly linear than exponential in these experiments. Growth yields usually varied between 0.2 and 0.4 (g dry cells)/(g acetate), although values were as high as 0.8 for a brief period during one experiment. Growth yields at a given acetate concentration were correlated by an equation of the form 1/Y = 1/YG + m/μ. A maintenance coefficient (m) of 0.17 (g acetate)/(g dry cell-hr) was observed at acetate concentrations of 4.5 and 10. g/1. A typical maximum growth yield (YG) of 0.51 (g dry cell)/(g acetate) was obtained at 4.5 g/1 acetate, but an unusually high YG of 1.33 was found at 10. g/1 acetate. Oxygen uptake measurements are compared with these cell yield measurements. Linear growth rates in expended culture were correlated by the equation K = 0.89–0.70 (S/S0) where K has units of (g dry cell)/(l-hr), S is the instantaneous acetate concentration, and S0 is the initial acetate concentration. The extended culture kinetic data are shown to be substantially different from continuous culture kinetic data. Reason for these differences are discussed in light of diffrences in the cell age distributions, as well as possible differences in experimental conditions.

Journal ArticleDOI
TL;DR: In the absence of bromide ion and at low bromine concentrations, the rates of addition of molecular bromines in acetic acid to a number of acetylenes have been found to follow the general equation.
Abstract: The rates of addition of molecular bromine in acetic acid to a number of acetylenes have been found to follow the general equationIn the absence of bromide ion and at low bromine concentrations (< ...


Journal ArticleDOI
TL;DR: In this paper, the influence of small amounts of different gases or vapors on the rate of carbon monoxide decomposition to carbon over an iron carbide catalyst was studied, and it was shown that hydrogen enhanced the strength of adsorption of carbon dioxide, thereby increasing its rate of decomposition.

Journal ArticleDOI
24 Jul 1970-Science
TL;DR: It is suggested that puff formation does not include an acetylation of histones, and that fixation with picric acid or formaldehyde retains incorporated [3H]acetate which is lost after fixation with ethanol and acetic acid.
Abstract: Fixation with picric acid or formaldehyde retains incorporated [ 3 H ] acetate which is lost after fixation with ethanol and acetic acid. Unlike [ 3 H ] uridine, [ 3 H ] acetate is diffusely incorporated into polytene chromosomes, and not preferentially into existing or newly induced puffs. It is suggested that puff formation does not include an acetylation of histones.

Journal ArticleDOI
TL;DR: The structure and desalination properties of cellulose acetate membranes cast from binary solutions and leached in water depend upon the nature of the casting solvent as discussed by the authors, and the location of the skin depends upon the type of the solvent.

Book ChapterDOI
TL;DR: This chapter describes the preparation of shikimate 5-phosphate, a slight modification of the procedure of Weiss and Mingioli that gives only one spot in descending chromatography on paper with butanol-1/acetic acid/water (100:6:2 v/v).
Abstract: Publisher Summary This chapter describes the preparation of shikimate 5-phosphate. This method is a slight modification of the procedure of Weiss and Mingioli. Aerobacter aerogenes is grown with rapid shaking (500 ml in a 2-liter flask) for 90 hours at 37°, and cells are removed by centrifugation. The culture fluid is assayed for shikimate-5-P by determining shikimate on appropriate samples before and after hydrolysis with potato acid phosphatase. In a typical hydrolysis, a solution of 0.5 micromole of shikimate-5-P, 500 micromoles of acetate buffer, pH 5.0, and 40 mg of a commercial preparation of potato acid phosphatase, is incubated at 37° for 3 hours, heated at 100° for 3 minutes, and clarified by centrifugation. The culture filtrate contained 1,020 mg of shikimate-5-P and 50 mg of shikimate per liter. Both preparations of shikimate-5-P gives only one spot in descending chromatography on paper with butanol-1/acetic acid/water (100:6:2 v/v).

Journal ArticleDOI
01 Sep 1970-Planta
TL;DR: Aqueous solutions of indole acetic acid, kinetin, gibberellic acid and abscisic acid were applied singly and in combination to the decapitated stem stump of Phaseolus seedlings to study the inhibition of bud growth.
Abstract: Aqueous solutions of indole acetic acid, kinetin, gibberellic acid and abscisic acid were applied singly and in combination to the decapitated stem stump of Phaseolus seedlings. Application of indole acetic acid will not completely replace the intact stem apex with regard to the inhibition of lateral bud extension. The greatest inhibition of bud growth is obtained when indole acetic acid is applied in combination with both kinetin and abscisic acid. Treatment with gibberellic acid causes massive bud growth even in the presence of indole acetic acid, kinetin and abscisic acid. Although both abscisic acid and kinetin have only a slight promoting effect on bud outgrowth when applied singly, these hormones will modify the effects of indole acetic acid and gibberellic acid.

Journal ArticleDOI
TL;DR: It is suggested that acetic acid could promote breakdown, and its removal as acetate esters or free acid would reduce the disorder as mentioned in this paper, however, the removal of acetic acids from apples would not necessarily reduce the incidence of breakdown.
Abstract: Increased rates of water loss, which reduced susceptibility of Jonathan apples to breakdown, caused a reduction in the level of acetic acid in the fruit. Increasing the level of acid, by the injection of acetic acid into the fruit, increased the incidence of breakdown. It is suggested that acetic acid could promote breakdown, and its removal as acetate esters or free acid would reduce the disorder.