79860-24-5

Upstream product

• 79860-18-7 C₁₇H₁₈N₄O₃ 
• 15900-43-3 13H-quinazoline[3,4-a]quinazolin-5,13-dione 
• 27259-73-0 2-(2'-aminophenyl)-4(3H)-quinazolinone 
• 118-92-3 anthranilic acid 
• 19589-44-7 5H-quinazolino[4,3-b]quinazoline-6,8-dione 
• 36567-87-0 2-(2'-nitrophenyl)-4(3H)-quinazolinone 
• 91-56-5 indole-2,3-dione 
• 24042-37-3 isamic acid 
• 19670-04-3 [2-(4-oxo-4H-benzo[d][1,3]oxazin-2-yl)-phenyl]-urea 
• 116465-86-2 N-(2-ureido-benzoylamino)-benzoic acid 
• 79860-05-2 2-dimethylammonio-(4H)-3,1-benzoxazine-4-one chloride 
• 28144-70-9 anthranilic acid amide 

Relevant academic research and scientific papers

Oxidative ring expansion of spirocyclic oxindole derivatives

Oxidation of the spirocyclic oxindole derivative, isamic acid 1, led to decarboxylation and ring expansion to quinazolino[4,5-b]quinazoline-6,8-dione 7 rather than, as previously believed, its isomer 6. The structure of 7 was confirmed by X-ray crystallography. Condensation of isatin (indole-2,3-dione) and 2-aminobenzamide led to the spirocyclic molecule, spiro[3H-indole-3,2′(1H)quinazoline]-2,4′(1H,3H)dione 8, which was also identified as an intermediate in the oxidation of isamic acid. Mild hydrolysis of 7 gave the 10-membered molecule 22. Isamic acid could easily be converted to N-nitrosoisamic acid, which when heated in ethanol underwent a ring expansion to a hydroximino derivative, 38, of compound 6. The structure of 38 was confirmed by X-ray crystallography.

HETEROCYCLIZATION WITH IMINIUM CHLORIDES, II. SYNTHESIS OF 4H--BENZOXAZINE-4-ONES AND QUINAZOLINONES

Reactions between methyl anthranilate and a variety of PI salts afforded 2-ammonio-4H--benzoxazine-4-one chlorides which were subjected to nucleophilic reactions.With primary amines, 2-ureidoanthraniloyl amides were obtained, which were smoothly cyclized in boiling acetic anhydride or dimethylformamide to give 1H,3H-quinazoline-2,4-diones.