Ethyl 3-bromopropionate → HCID 131713564, compound

Participants

Reaction Steps

Using the same reactions described above, 7.23 g (0.03) of ethyl β-bromopropionate and 7.33 g (0.04 m) of proline benzyl ester hydrochloride gave N-(2-carbethoxy)ethyl-L-proline, benzyl ester (4.6 g, 50.2%). This compound (4.6 g, 0.015 m) was hydrogenated over palladium-on-carbon to give 2.96 g (78%) of N-(2-carbethoxy)ethyl-L-propline, hydrochloride, m.p. 169°-171°. This compound (2.42 g, 0.0096 m) was condensed with 2.25 g (0.0072 m) of L-alanyl-L-proline, benzyl ester hydrochloride in the dicyclohexylcarbodiimide procedure to give 0.8 g of N-(2-carbethoxy)ethyl-L-prolyl-L-alanyl-L-proline, benzyl ester. The pro-drug precursor was hydrolyzed with barium hydroxide in aqueous methanol to give 0.498 g (64%) of N-(2-carboxyethyl)-L-prolyl-L-alanyl-L-proline, m.p. 133°-136°.

Provenance & Evidence