HCID 178468488, compound → HCID 178524024, compound

Participants

Reaction Steps

8-Ethoxycarbonyl-2,3-dihydroxythieno[3,2-f]quinoxaline (2.0 g, 6.9 mmol) was stirred in 30 ml of 2N sodium hydroxide at room temperature for 2 h. The solution was filtered, and after acidification of the filtrate with 4M hydrochloric acid, the resulting precipitate was collected by filtration and washed with water. The crude product was dissolved in 2N sodium hydroxide and reprecipitated with 4M hydrochloric acid to give 0.94 g (52%) of the carboxylic acid, m.p. >350° C. dec.; IR (KBr): 3300-2200, 1690 cm-1.

Provenance & Evidence