N-Acetylanthranilic acid

Preparation of Intermediate Compound 4-Chloro-5-Sulfamyl-N-Acetylanthranilic Acid To a hot solution (80°C) of 366 g (1.482 mols) of magnesium sulfate (Epsom salts) in 2.8 liters of water was added 130 g (0.495 mol) of powdered 5-chloro-2-methyl-4-sulfamyl-acetanilide. With stirring and maintaining the temperature at 83°C, 234 g (1.482 mols) of potassium permanganate was added portionwise over a period of 2 hours. The mixture was then kept at 85°C with stirring for an additional 3 hours. By this time the pink color of the permanganate had been discharged. 

Preparation of Intermediate Compound 2-Methyl-3-o-Tolyl-6-Sulfamyl-7-Chloro-4(3H)-Quinazoiinone Set up a 5-liter 3-necked flask fitted with a stirrer, condenser and a drying tube. To a stirred mixture of 100 g (0.342 mol) of powdered 4-chloro-5-sulfamyl-N-acetylanthranilic acid, 40.2 g (0.376 mol) of o-toluidine and 2.0 liters of dry toluene was added dropwise, over a period of 15 minutes, 21.7 ml (34.1 g) (0.248 mol) of phosphorus trichloride. The mixture was then refluxed for 10 hours. The solid turned somewhat gummy towards the latter part of the first hour. The mixture then became more free flowing as heating was continued. Let stand overnight. The yellow solid was filtered, washed with toluene and dried. The toluene filtrate was discarded. The dried solid was triturated with 1.5 liters of 10% sodium bicarbonate, filtered and the cake washed with water. The filtrate on acidification yielded 11.5 g of the starting acid. The damp product was dissolved in 4,5 liters of 95% ethanol and the solution treated with charcoal and filtered. On cooling filtrate yielded 69.5 g (55.5%) of the title compound, MP 271.5° to 274°C. 

Quinaldine (2-methyl-quinoline) (2) 2-methyl-4(lH)-quinolinone (3) 3 -hydroxy-2-methyl-4( 1 H)quinolinone (4) N-acetylanthranilic acid (5) Anthranilic acid (6) Catechol (1) Quinoline (2) 2(lH)quinolinone (3) 8-hydroxy-2(lH)quinolinone (4) 8-hydroxycoumarin (5) 2, 3-dihydroxyphenylpropionic acid... 

Acetic Anhydride Acetone Dicarboxylic Acid N-Acetylanthranilic Acid N-Acetylmescaline Aluminum Foil ( ) Ammonium Acetate Anthranilic Acid Barbituric Acid Benzaldehyde Benzocaine... 

Acetylacetaldehyde dimethyl acetal, d435 Acetylacetone, p31 N- Acetylanthranilic acid, al 1 Acetylbenzene, a31 Acetylcyclopropane, c368 Acetylene dichlorides, d 79, dl80... 

Hydroiodic Acid (57%) Isosafrole Methylamine N-Acetylanthranilic Acid N-Methylephedrine... 

Upon basic hydrolysis, aconorine afforded the parent amino alcohol (80) and an N-acetylanthranilic acid. On treatment with acetyl chloride,... 

Lappaconitine (C32H44N208) has been isolated from A. septentrionale Koelle (103), A. orientale (104), and A. excelsum Popov (105). Alkaline hydrolysis of lappaconitine yielded the parent alkamine, lappaconine (C23H37NO6), and the N-acetylanthranilic acid. On the basis of extensive chemical studies, in 1969 Marion and his co-workers (106) assigned structure 86 to lappaconine. Meanwhile, Birnbaum reported (107,108) an X-ray analysis of lappaconine hydrobromide and confirmed the proposed structure for lappaconine. Subsequently, the Soviet workers assigned (109) the -acetylanthranilic ester moiety of lappaconitine (87) to the C-4 position. 

In the latter pathway anthranilic acid and aspartic acid are used to construct peganine. In accord with this it has been shown recently that anthranoylaspartic acid (155) is a fairly specific precursor for peganine (154) in A. vasica N-Acetylanthranilic acid (153) is built into peganine intact, so perhaps the most important precursor for peganine may be (156). 

Acetic acid Acetic anhydride Acetone Acetyl chloride N-Acetylanthranilic acid Ammonium formate Ammonium hydroxide Anthranilic acid Benzaldehyde Benzene Benzyl chloride Benzyl cyanide... 

In 1905, Bogert and Chambers described the synthesis of 32 via the acetanthranil intermediate 31, which was formed by heating 2-amino-6-nitrobenzoic acid (30) with acetic anhydride." It was reported that the yield for this reaction was nearly quantitative. This modification was compared to other variations known at that time, including heating the ammonium salt of anthranilic acid with formamide and heating the ammonium salt of N-acetylanthranilic acid, and proved to be superior. A 4-quinazolone without a substituent at the 3-position (35) has also been prepared by this method. ... 

N-Acetylanthranilic acid anilide refluxed 1 hr. on a sand bath with acetic anhydride and freshly calcined Na-acetate -> 2-methyl-3-phenyl-4-quinazolone. Y 86%. F.e. and procedures s. P. A. Petyimin and Y. V. Kozhevnikov, IK. 30, 2352 (1960) C. A. 55, 9402c. 

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