L-Tyrosine → HCID 178512890, compound

Participants

Reaction Steps

In 5 ml of mixed solution of trifluoroacetic acid-thioanisole (9:1) was dissolved 400 mg of Boc-Tyr-Arg(Mtr)OH and the resulting mixture was allowed to stand at room temperature for 2 hours. The trifluoroacetic acid was distilled off under reduced pressure, ether was added to the residue and the resulting precipitate was collected by filtration. The precipitate was dissolved in a small amount of water, passed through a column (1×10 cm) of Amberlite IRA-410 (acetate-form) and lyophilized. The lyophilizate was dissolved in a small amount of water, chromatographed on a carboxymethyl-cellulose column (2.2×8 cm) and eluted by the linear gradient method using water (300 ml) and 0.1 M ammonium acetate (300 ml). The fractions from 100 to 150 ml were pooled and lyophilized. Yield 175 mg, [α]D21 -17.4° (c=0.5, H2O); amino acid analysis (acid hydrolysis): Arg 1.00(1), Tyr 0.94(1); average recovery 86.5%.

Provenance & Evidence