Ethyl isocyanate → 1-[3-[[(ethylamino)carbonyl]thio]propanoyl]-L-proline

Participants

Reaction Steps

Ethylisocyanate (0.45 ml) is added to a solution of 1-(3-mercaptopropanoyl)-L-proline (1 g) in a mixture of N sodium hydroxide (5 ml) and pyridine (5 ml). The solution is heated at 40° for four hours and concentrated in vacuo. The residue is distributed between 0.1 N hydrochloric acid and ethyl acetate. The organic layer is washed with water, dried over magnesium sulfate and concentrated to dryness to yield 1-[3-[[(ethylamino)carbonyl]thio]propanoyl]-L-proline. The dicyclohexylammonium salt is prepared by adding dicyclohexylamine to a solution of the free acid in ethyl acetate, m.p. 150°-152°.

Provenance & Evidence