N-Phenylanthranilic acids

N-Phenylanthranilic acid may be prepared by the action of aniline upon c-chlorobenzoic acid in the presence of anhydrous potassium carbonate and a little copper oxide  

The compound is employed inter alia as an indicator In titrations with potassium dichromate and ceric siilphate solutions. 

In a 1 litre round-bottomed flask, equipped with an air condenser, place a mixture of 44 g. of o-chlorobenzoic acid (Section IV,157) (1), 156 g. (153 ml.) of redistilled aniline, 41 g. of anhydrous potassium carbonate and 1 g. of cupric oxide. Reflux the mixture in an oil bath for 2 hours. Allow to cool. Remove the excess of aniline by steam distillation and add 20 g. of decolourising carbon to the brown residual solution. Boil the mixture for 15 minutes, and filter at the pump. Add the filtrate with stirring to a mixture of 30 ml. of concentrated hydrochloric acid and 60 ml. of water, and allow to cool. Filter off the precipitated acid with suction, and dry to constant weight upon filter paper in the air. The yield of iV-phenylanthranilic acid, m.p. 181-182° (capillary tube placed in preheated bath at 170°), is 50 g. This acid is pure enough for most purposes. It may be recrystaUised as follows dissolve 5 g. of the acid in either 25 ml. of alcohol or in 10 ml. of acetic acid, and add 5 ml. of hot water m.p. 182-183°. 

N Phenylanthranilic acid may be prepared by the action of aniline upon 

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Procedure (copper in crystallised copper sulphate). Weigh out accurately about 3.1 g of copper sulphate crystals, dissolve in water, and make up to 250 mL in a graduated flask. Shake well. Pipette 50 mL of this solution into a small beaker, add an equal volume of ca AM hydrochloric acid. Pass this solution through a silver reductor at the rate of 25 mL min i, and collect the filtrate in a 500 mL conical flask charged with 20 mL 0.5M iron(III) ammonium sulphate solution (prepared by dissolving the appropriate quantity of the analytical grade iron(III) salt in 0.5M sulphuric acid). Wash the reductor column with six 25 mL portions of 2M hydrochloric acid. Add 1 drop of ferroin indicator or 0.5 mL N-phenylanthranilic acid, and titrate with 0.1 M cerium(IV) sulphate solution. The end point is sharp, and the colour imparted by the Cu2+ ions does not interfere with the detection of the equivalence point. 

Hexacyanoferrate(U). This can be determined by titration in 1M H2S04 using N-phenylanthranilic acid. 

N-phenylanthranilic acid org chem (C6H5NH)C6H4C00H A crystalline compound, soluble in hot alcohol decomposes at 183-184°C used to detect vanadium in steel. en fen-3l,an-thr3 nihik as-cd phenylbenzene See biphenyl. fen-3l ben,zen ... 

Col crysts, mp 354° insol in w, si sol in ale or eth. It was first prepd in lS80(Ref 2) by treating acridine with chromic acid, but its identity was not established until 1892 (Ref 3). Its method of prepn by heating on a water bath N-phenylanthranilic acid with coned HaS04 is given in Ref 4. Can be nitrated to form nitrocompds Refs l)Beil 21,335,(312) [2801 2)C. 

Anilinobenzoic Acid Diphenylaminocarboxy-lic Acid or N-Phenylanthranilic Acid,CtHs-NH CgH4 COOH. Several isomers are described in Beil 14,327,(533, 585) [213]... 

Phenylamino-trimethylolmethane. See Anilinotrimethylolme thane A441-L Phenylaniline. See Aminobiphenyl A191-R N-Phenylanthranilic Acid. See Anilinobenzoic Acid A421-R... 

We chose 60 compounds with pl50 values ranging from 7.1 to 4.9 and subjected them to regression analysis using several physicochemical parameters (Table I). The 60 compounds contained variations in six positions of the basic structure. Quantitative structure-activity correlations with as many individual uncouplers in one equation have not yet been published. As far as we know, the Hansch approach has been applied to uncouplers of oxidative phosphorylation only twice first in 1965 by Hansch and co-workers to phenols and recently by Muraoka and Terada to N-phenylanthranilic acids. From Muraoka s data we recalculated the correlation with w and o- and obtained an equation which gave the best fit (last equation, Figure 3). 

Naphthalene (55) and anthracene (57) are hydrogenated to decalin (56) and perhydroanthracene (58) catalyzed by [Co(C3H5) P(OMe)3 3]. - Rh -N-phenylanthranilic acid anchored to polystyrene beads can also hydrogenate naphthalene to decalin. ... 

N-Phenylanthranilic acid, 22, 5 Phenyl azide, 22, 96 -Phenylazobenzoic acid, 25, 86 -Phenylazobenzoyl chloride, 25, 87 Phenylbenzoyldiazomethane, 20, 48 a-Phenyl-0-benzoylpropionitrile, 27, 33 Phenyl cinnamate, 20, 77... 

The measurement of urinary uronic acid has been used as an early indicator in the development of renal papillary necrosis in rats given multiple doses of N-phenylanthranilic acid or mefenamic acid [217]. A significant elevation of uronic acid in urine occurred was well ahead of the development of histological evidence of renal papillary necrosis. The biochemical basis of these changes appears to be related to acid mucopolysaccharides accumulation [218]. 

The fenamates are a family of NSAIDs first discovered in the 1950s that are derivatives of N-phenylanthranilic acid. They include mefenamic, meclofenamic, and flufenamic acids. They have no clear advantages over several other NSAIDs, and frequently cause GI side effects. 

N-Phenylanthranilic acids. Copper-catalyzed displacement of halogen in o-halobenzoic acids by aniline may be performed in refluxing water. 

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