Ammonia → HCID 178455899, compound

Participants

Reaction Steps

80 mg of H-Arg-Arg-Pro-Phe-His-Sta-Ile-His-Lys-OMe (Example 7) are dissolved in 1.5 ml of H2O and the pH value is adjusted to 5.5 by the addition of 0.1N NH3. 8 μl of a 1% aqueous trypsin solution are added and the pH value is maintained at 5.5 by the addition of 0.1N NH3 by means of a pH stat. After approximately 20 minutes the absorption of base is complete, whereupon 350 μl of glacial acetic acid are added and the whole is heated for 2 minutes in a boiling water bath. The solution is concentrated to dryness, the residue is dissolved in 2 ml of 0.05N AcOH and, in order to separate off the inactivated enzyme, pumped through a column (φ=1.2 cm, length=25 cm) of Biogel P-10 polyacrylamide gel, exclusion limit at a molecular weight of 20 000; manufacturer: Bio-Rad, Richmond, Calif., USA). The fraction having a molecular weight matching the peptide mentioned below, which is ascertained by UV detection, is concentrated to a small volume and lyophilised, yielding H-Arg-Arg-Pro-Phe-His-Sta-Ile-His-Lys-OH; Rf (D)=0.12; Rf (M)=0.07; Rf (N)=0.05.

Provenance & Evidence