Hydrochloric Acid → Methyl 2-(methylthio)-4-ureidothiazole-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

In 150 mL methylene chloride, 4-amino-2-methylthio-5-thiazolcarboxylic acid methyl ester (0.05 mol) was dissolved and cooled to −78° C. under nitrogen gas. Stirring, 0.07 mol (1.4 eq) of chlorosulfonyl isocyanate was added slowly to give a brown solution. The reaction was warmed slowly to 0° C. and a white precipitate forms. After 30 minutes, the solution was evaporated under vacuum, resuspended in 40 mL of 6N hydrochloric acid (4 eq) and heated to 100° C. After 30 minutes, the solution was cooled to room temp, neutralized with saturated sodium carbonate followed by saturated sodium bicarbonate. The white solid was isolated by filtration to give methyl 2-(methylthio)-4-ureidothiazole-5-carboxylate 76.

Provenance & Evidence