Trifluoroacetic acid → (R)-1-[3-[[3-[(R)-2-Carboxy-pyrrolidin-1-yl]-3-oxo-propyl]-(2-methoxy-ethyl)-amino]-propionyl]-pyrrolidine-2-carboxylic acid trifluoroacetate

Participants

Reaction Steps

To a stirred solution of 150 mg (0.29 mmol) (R)-1-[3-[[3-[(R)-2-tert-butoxycarbonyl-pyrrolidin-1-yl]-3-oxo-propyl]-(2-methoxy-ethyl)-amino]-propionyl]-pyrrolidine-2-carboxylic acid tert-butyl ester in 5 ml dichloromethane at 0° C. was added dropwise 1.0 ml trifluoroacetic acid and stirring continued for 16 h at room temperature. Concentration in vacuo and azeotroping three times with chloroform on a rotary evaporator afforded, after resuspension in water and subsequent lyophilisation, 100 mg (67%) of the title compound as a yellow oil. MS m/e (%): 436 (M+Na+, 35), 414 (M+H+, 100).

Provenance & Evidence