Hydrochloric Acid → HCID 57061276, compound

Participants

Reaction Steps

To the solution obtained in Example V containing 4,7-dihydro-7-ethyl-2-carbomethoxyiminomethyl-4-oxo-thieno[2,3-b]pyridine-5-carboxylic acid ethyl ester was added 0.15 g (3.7 mmols) of sodium hydroxide in 5 ml of water. The medium was maintained under stirring for 3 hours at room-temperature. The precipitate formed was filtered out, washed with ethanol and then with ethyl ether. The product so obtained was then taken up in 200 ml of water and the solution was acidified with concentrated hydrochloric acid. The precipitate so formed was filtered out, washed with water and then with ethanol. After drying, 4,7-dihydro-7-ethyl-2-carboxymethoxyiminomethyl-4-oxo-thieno[2,3-b]pyridine-5-carboxylic acid was obtained in a yield of 40%.

Provenance & Evidence