Acetate → HCID 178476395, compound

Participants

Reaction Steps

A solution of 300 mg. of Nα -benzyloxycarbonyl-L-glutaminyl-L-tryptophyl-L-seryl-L-tyrosyl-D-phenylalanyl-L-leucyl-L-arginyl-L-proline N-ethylamide hydrochloride in 100 ml. of methanol is put on a column of Dowex 1 × 2 (acetate form) resin 1.8 by 23 cm. and the material is eluted with methanol, collecting 40 ml. fractions. Fractions 2 to 5 on standing give an insoluble product. They are combined and filtered and the filtrate is concentrated to 30 ml. and diluted with ether (150 ml.). The product which precipitates is filtered off, washed with ether and dried at 50° C. under reduced pressure to give Nα -benzyloxycarbonyl-L-glutaminyl-L-tryptophyl-L-seryl-L-tyrosyl-D-phenylalanyl-L-leucyl-L-arginyl-L-proline N-ethylamide acetate salt [α]D23 -29° (c 1.00, DMF); λmax 289.5 E11 41.7 λmax 280 E11 54.3.

Provenance & Evidence