Electric Literature of 5521-55-1, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 5521-55-1 as follows.
Step 5 4-[3-(4-Chloro-benzoylamino)-propoxy]-3-[3-(5-methyl-pyrazin-2-yl)-ureido]-benzoic acid ethyl ester 5-Methyl-pyrazine-2-carboxylic acid (0.5 g, 3 mmol) was heated in toluene (50 mL) with stirring. Diphenyl phosphoryl azide (DPPA) was added. The temperature was increased to 100 C. over 10 minutes and maintained for a further 15 minutes, until the evolution of gas had ceased. During this time, the solution changed colour from orange to dark red/brown. 3-Amino-4-[3-(4-chloro-benzoylamino)-propoxy]-benzoic acid ethyl ester (1.15 g, 3 mmol), in toluene (20 mL), was added via syringe at 100 C. and stirred for 30 minutes. The heat was removed and the reaction mixture was cooled to room temperature. The resulting precipitate was collected via filtration to give a white solid (888 mg, 58%). 1H NMR (400 MHz, DMSO-d6) delta 10.17 (s, 1H), 8.87 (s, 1H), 8.65 (s, 1H), 8.66 (s, 1H, broad), 8.17 (s, 1H), 7.86 (d, 2H), 7.65 (dd, 1H), 7.52 (d, 2H), 7.15 (d, 1H), 4.30 (q, 2H), 4.24 (t, 2H), 3.52 (m, 2H), 2.39 (s, 3H), 2.16 (m, 2H), 1.31 (t, 3H). LCMS: method A, Rt=3.33 min, [MH+=512].
According to the analysis of related databases, 5521-55-1, the application of this compound in the production field has become more and more popular.
Reference:
Patent; Millennium Pharmaceuticals, Inc.; US2005/176733; (2005); A1;,
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