反应详情

A suspension of 0.315 g of the product of Step B, 35 ml of water, 12 ml of ethanol and 6 ml of 1 N sodium hydroxide was stirred overnight to obtain a suspension of the white sodium salt which was acidified with concentrated hydrochloric acid. The mixture was filtered to obtain 0.28 g of 4-carbamoyl-imidazo-[1,2-a]-quinoxaline-2-carboxylic acid in the form of a buff crystalline solid melting at 298°-300° C.

1. customto obtain
2. filtrationThe mixture was filtered