55321-99-8

131543-46-9

62009-47-6

55321-99-8

The general procedure for the synthesis of 3-hydroxypyrazine-2-carboxamide from the compound (CAS:131543-46-9) and 2-aminomalonamide was carried out as follows: firstly, diethylaminomalonate (in the form of hydrochloric acid) was dissolved in water, and pH was adjusted by adding sodium bicarbonate to a value greater than 7. Subsequently, an extraction operation was carried out, and the organic phase was evaporated under reduced pressure. The product obtained was quantitatively converted to aminodicarbonamide by treating the product with an aqueous ammonia solution at 80 °C overnight. The product obtained in this step does not require further purification and can be directly dissolved in water for the next reaction. Next, glyoxal sodium bisulfite hemihydrate was added to this aqueous solution and the reaction mixture was stirred at 90°C for 3 hours. After completion of the reaction, the reaction mixture was adjusted to alkaline with 58% NH4OH solution. A 30% H2O2 solution was added dropwise to the rapidly stirred cold solution at 0°C. The reaction mixture was allowed to stand at room temperature to induce precipitation of 2-hydroxy-3-carboxamide pyrazine. Finally, the solid product was collected in 63% yield and purified by partial recrystallization. References: [J. Med. Chem. 1983, 26, 283-86], [J. Heterocyclic Chem. 1979, 16, 193].