1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → N-[(R)-1-{3-(1-tert-butoxycarbonyl-4-piperidyl)propionyl}-3-piperidylcarbonyl]-3-ethynyl-beta-alanine ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a mixture of ethyl 3-amino-2-ethynylpropionate hydrochloride (0.5 g), (R)-1-[3-(1-tert-butoxycarbonyl-4-piperidyl)propionyl]-3-piperidinecarboxylic acid (1.04 g) and 1-hydroxybenztriazole (0.38 g) in N,N-dimethylformamide (5 ml) was added 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (0.51 ml) under stirring at 0° C. After stirring at ambient temperature overnight, the mixture was poured into water and extracted with ethyl acetate. The extract was washed with water, brine and dried over MgSO4, and evaporated in vacuo. The residue was purified by chromatography on silica gel eluting with CHCl3:MeOH=(100:1) to give N-[(R)-1-{3-(1-tert-butoxycarbonyl-4-piperidyl)propionyl}-3-piperidylcarbonyl]-3-ethynyl-β-alanine ethyl ester as an oil (1.38 g).

Provenance & Evidence