3-Nitroanthranilic acid

Reductive cyclization of substituted jV-(2 -fluorophenyl)-3-nitroanthranilic acids 10 provides a reliable synthetic route by reductive ring closure exclusively to the fluoro-substituted carbon to yield 6-, 8-, and 9-substituted phenazine-1-carboxylic acids 11 in good yield.This ring closure occurs via S Ar displacement of fluoride. 

Nitroanthranilic acid (60 g) and 120 g freshly distilled formamide were heated in an open beaker in an oil bath at an inside temperature of 155-160°C for 6 h. The dark residue, after cooling, was pulverized and washed with 5% NaHC03 solution, then with water, and dried to afford 42 g crude 8-nitroquinazolone-4, in a yield of 67%, m.p. 240-248°C. The crude product was then recrystallized from nitrobenzene (100 mL per 15 g product) with a liberal use of charcoal for decolorization. The crystal was washed with ether to remove residual nitrobenzene, and pale yellow needles were obtained, which melted at 250-251°C. 

Dinitro-2-nitraminobenzoic Acid or 3,4-Dinftro>N>nitroanthranilic Acid. Yel, unstable solid, which may be stored for some time in the dark. No mp given. Sol in ale eth less sol in w nearly insol in chlf benz. Was... 

Besson and co-workers have investigated the microwave-assisted multi-step (seven steps) synthesis of thiazoloquinazolinone derivatives, utilising commercially available nitroanthranilic acids as the initial precursors69. Comparison of the conventional thermal heating and microwave heating approaches demonstrated that the overall time for the multi-step synthesis could be considerably reduced (by a factor of 8) by adopting the microwave-heated reaction methods (Scheme 3.44). In addition, the reactions were cleaner and the products could be purified rapidly. For the microwave-heated multi-step synthesis, the overall yield of the final product was increased by a factor of 2, which enabled the scale of the overall synthesis to be increased from 0.2 to 1 g. 

The nitroanthranilic acid 1150 reacts with allyl bromide in the presence of v -butyl nitrite to furnish the dihydroisocoumarin 1151 in poor yield (Equation 443) <2003JOC1911>. 

Nitroanthranilic acid reacted with p-toluenesulfonyl chloride in pyridine to give the benzoxazine 217 and the 2-nitropyrido[2,l- i]quinazoline 218 in 26 and 72% yields, respectively, at room temperature, and in 59 and 29% yields, respectively, at 1... 

King RR, Lawrence CH, Calhoun LA. 1998. Unusual production of 5-nitroanthranilic acid by Streptomyces scabies. Phytochemistry 49 1265-1267. 

C8H6O6N2 2-Carboxy-3-nitrobenzamide KOBr 6-Nitroanthranilic acid 86% 51,104... 

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