THE IONIZATION CONSTANTS OF p-NITROPHENYLACETIC AND PHENYLMALONIC ACIDS

1933 ◽  
Vol 8 (5) ◽  
pp. 447-449 ◽  
Author(s):  
Steward Basterfield ◽  
James W. Tomecko
Keyword(s):  
Benzoic Acid ◽  
Nitro Group ◽  
Malonic Acid ◽  
Phenylacetic Acid ◽  
Ionization Constants ◽  
Side Chain ◽  
Cooh Group ◽  
Conductivity Data ◽  
Nitrobenzoic Acid ◽  
Phenylmalonic Acid

The ionization constants of p-nitrophenylacetic and phenylmalonic acids have been determined from conductivity data. The value of K for p-nitrophenylacetic acid at 25 °C. is 1.04 × 10−4, about twice that of phenylacetic acid. The nitro group in the nucleus has not as powerful an effect on the ionization when the COOH group is in the side chain as it has when both nitro group and COOH are in the nucleus. K for p-nitrobenzoic acid is six times as great as K for benzoic acid. K for phenylmalonic acid is 2. 77 × 10−3 as compared with 1.6 × 10−3 for malonic acid.

Ionization constants of benzoic and mononitrobenzoic acids in formamide

1972 ◽  
Vol 25 (5) ◽  
pp. 941 ◽  
Author(s):  
UN Dash ◽  
B Nayak
Keyword(s):  
Benzoic Acid ◽  
Ionization Constants ◽  
Weak Acids ◽  
General Behaviour ◽  
Nitrobenzoic Acid

The ionization constants of benzoic acid and of three mononitrobenzoic acids, at 25� in formamide, have been determined from the measurements of the electro-motive forces of the cells Pt,H2/HA(m1),KA(m2)KCl(m3)AgCl-Ag The values of the ionization constants for benzoic acid, o-nitrobenzoic acid, m-nitro-benzoio acid, and p-nitrobenzoic acid thus calculated from e.m.f. data are 4.37 x 10-7, 3.89 x 10-5, 3.98 x 10-6 and 1.32 x 10-6, respectively. These values are smaller than those in water, and are in agreement with a general behaviour exhibited by weak acids in solvents of this class.

Enhanced Infrared ATR Spectra of O-, m-, and p-Nitrobenzoic Acid with Ag Films

1989 ◽  
Vol 43 (3) ◽  
pp. 549-552 ◽  
Author(s):  
Simona Badilescu ◽  
P. V. Ashrit ◽  
Vo-Van Truong ◽  
I. I. Badilescu
Keyword(s):  
Molecular Structure ◽  
Organic Compound ◽  
Benzoic Acid ◽  
Nitro Group ◽  
Structural Features ◽  
Spectral Features ◽  
Nitrobenzoic Acid ◽  
Strongly Interacting

The dependence of enhancement of the infrared bands by thin Ag films on the molecular structure of the organic compound was investigated. A different enhancement behavior for the three isomers—ortho-, meta-, and paranitrobenzoic acids—was observed and accounted for by structural features. The presence of the ionized species of the acids in the monolayer bonded to Ag was found, and the spectral features of the monolayer and bulk compound were compared. The splitting of the antisymmetric stretching band of the nitro group for metanitro benzoic acid strongly interacting with Ag was observed. The correlation of the morphology of the Ag surface to the magnitude of the achieved enhancement is discussed.

Catabolism of phenylacetic acid in Penicillium rubens. Proteome-wide analysis in response to the benzylpenicillin side chain precursor

2018 ◽  
Vol 187 ◽  
pp. 243-259 ◽  
Author(s):  
Mohammad-Saeid Jami ◽  
Juan-Francisco Martín ◽  
Carlos Barreiro ◽  
Rebeca Domínguez-Santos ◽  
María-Fernanda Vasco-Cárdenas ◽  
...  
Keyword(s):  
Phenylacetic Acid ◽  
Side Chain

Biosynthese von p-Hydroxybenzoesäure und anderer Benzoesäuren in höheren Pflanzen

1964 ◽  
Vol 19 (5) ◽  
pp. 398-405 ◽  
Author(s):  
M. H. Zenk ◽  
G. Müller
Keyword(s):  
Benzoic Acid ◽  
Protocatechuic Acid ◽  
Higher Plants ◽  
Side Chain ◽  
Hydroxybenzoic Acid ◽  
Benzoic Acids ◽  
Coumaric Acid ◽  
Cinnamic Acids ◽  
Feeding Experiments ◽  
Catalpa Ovata

Feeding experiments with glucose- (2-14C), phenylalanine- (3-14C), tyrosine- (3-14C) and p-coumaric acid- (3-14C) showed that the latter three substances are incorporated in good yields into p-hydroxybenzoic acid in leaves of Catalpa ovata. Kinetic experiments showed that p-hydroxybenzoic acid is formed from phenylalanine via p-coumaric acid and the subsequent β-oxidation of the side chain. p-Hydroxybenzoic acid can also be synthetised by hydroxylation of benzoic acid, but this does not seem to be the biosynthetic route in Catalpa.Phenylalanine- (3-14C) is also incorporated into benzoic acid, protocatechuic acid, and vanillic acid by different plants; the radioactivity of the β-C atom of the amino acid was found in each case to be located in the carboxyl group of the C6 — C1 acid. This suggests that in higher plants the benzoic acids are formed from the corresponding cinnamic acids via β-oxidation.

scholarly journals Biodegradation ofn-Alkylcycloalkanes and n-Alkylbenzenes via New Pathways in Alcanivorax sp. Strain MBIC 4326

2001 ◽  
Vol 67 (4) ◽  
pp. 1970-1974 ◽  
Author(s):  
Tapan K. Dutta ◽  
Shigeaki Harayama
Keyword(s):  
Carboxylic Acid ◽  
Benzoic Acid ◽  
Side Chain ◽  
Alkyl Side Chain ◽  
Cyclohexanecarboxylic Acid ◽  
Long Chain

ABSTRACT The degradation of long-chain n-alkylbenzenes andn-alkylcyclohexanes by Alcanivorax sp. strain MBIC 4326 was investigated. The alkyl side chain of these compounds was mainly processed by β-oxidation. In the degradation ofn-alkylcyclohexanes, cyclohexanecarboxylic acid was formed as an intermediate. This compound was further transformed to benzoic acid via 1-cyclohexene-1-carboxylic acid.

scholarly journals Biosynthesis of phytoquinones. Homogentisic acid: a precursor of plastoquinones, tocopherols and α-tocopherolquinone in higher plants, green algae and blue–green algae

1970 ◽  
Vol 117 (3) ◽  
pp. 593-600 ◽  
Author(s):  
G. R. Whistance ◽  
D. R. Threlfall
Keyword(s):  
Green Algae ◽  
Phenylacetic Acid ◽  
Higher Plants ◽  
Chlorella Pyrenoidosa ◽  
Homogentisic Acid ◽  
Side Chain ◽  
Methyl Groups ◽  
Blue Green Algae ◽  
Hydroxyphenylacetic Acid ◽  
Tracer Experiments

1. By means of 14C tracer experiments and isotope competition experiments the roles of d-tyrosine, p-hydroxyphenylpyruvic acid, p-hydroxyphenylacetic acid, phenylacetic acid, homogentisic acid and homoarbutin (2-methylquinol 4-β-d-glucoside) in the biosynthesis of plastoquinones, tocopherols and α-tocopherolquinone by maize shoots was investigated. It was established that d-tyrosine, p-hydroxyphenylpyruvic acid and homogentisic acid can all be utilized for this purpose, whereas p-hydroxyphenylacetic acid, phenylacetic acid and homoarbutin cannot. Studies on the mode of incorporation of d-tyrosine, p-hydroxyphenylpyruvic acid and homogentisic acid showed that their nuclear carbon atoms and the side-chain carbon atom adjacent to the nucleus give rise (as a C6-C1 unit) to the p-benzoquinone rings and nuclear methyl groups (one in each case) of plastoquinone-9 and α-tocopherolquinone and the aromatic nuclei and nuclear methyl groups (one in each case) of γ-tocopherol and α-tocopherol. 2. By using [14C]-homogentisic acid it has been shown that homogentisic acid is also a precursor of plastoquinone, tocopherols and α-tocopherolquinone in the higher plants Lactuca sativa and Rumex sanguineus, the green algae Chlorella pyrenoidosa and Euglena gracilis and the blue–green alga Anacystis nidulans.

scholarly journals Urinary aromatic acid excretion by fed and fasted sheep in relation to protein metabolism in the rumen

1973 ◽  
Vol 30 (2) ◽  
pp. 251-267 ◽  
Author(s):  
A. K. Martin
Keyword(s):  
Benzoic Acid ◽  
Urinary Excretion ◽  
Phenylacetic Acid ◽  
Acid Output ◽  
Starvation Period ◽  
Regression Equations ◽  
Abomasal Infusion ◽  
Prolonged Retention ◽  
Field Beans

1. Two adult wether sheep were maintained on a diet of hay and two on a diet of dried grass for 3 weeks before starvation for a period of 10 d. Urinary excretion of the following acids was determined when the animals were fed and when they were fasted: total diethyl ethersoluble acids of hydrolysed and unhydrolysed urine, hippuric acid, benzoic acid and phenylacetic acid. By the 5th day of fasting, urinary output of all acids had attained stable levels that did not change during the remaining starvation period. The output of all urine fractions except phenylacetic acid declined rapidly during the first 4 d of fasting: phenylacetic acid output by all sheep increased to a maximum during the first 4 d of fast and then declined to stable values (0·42–0·73 g/24 h) which were greater than those observed when the sheep were fed. It is concluded that prolonged retention of food and microbial residues in the digestive tract is responsible for the large output of phenylacetic acid in the urine of fasted sheep.2. Solutions of casein which supplied between 6·3. and 26·5 g nitrogen/24 h were infused into the rumens (fifteen experiments) or abomasums (sixteen experiments) of eight adult wether sheep. Ruminal infusions of casein caused increments in the urinary excretion of diethyl ethersoluble acids and phenylacetic acid. Both these increments were described by linear regression equations (P < 0·001), the coefficients of which showed that 284 ± 44 and 220 ± 21 mg benzoic acid equivalent were excreted as diethyl ether-soluble acids and phenylacetic acid respectively per g casein N infused. The phenylacetic acid excreted was equivalent to 95% of the phenylalanine of the infused casein. No increments in urinary benzoic acid were observed. One sheep scoured when it was given an abomasal infusion of casein. This was the only animal to show any increment in urinary aromatic acids when casein was infused into the abomasum.3. When four sheep were given two rations containing an excess of carbohydrate as sugarbeet pulp or rolled barley, 11 and 16% respectively of their phenylalanine intakes were excreted in the urine as phenylacetic acid. When the same sheep were given two rations containing an excess of N as linseed meal or field beans, 51 and 59% respectively of their phenylalanine intakes appeared in the urine as phenylacetic acid.4. Methods for the determination of creatinine, and of benzoic, phenylacetic, 3-phenylpropionic, cinnamic, hippuric and phenaceturic acids are described.5. It is suggested that the amount of phenylacetic acid excreted in the urine is a measure of the equilibrium occurring in the rumen between catabolism of phenylalanine and reutilization of the products of catabolism for phenylalanine synthesis.

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