Glycine → HCID 178448169, compound

Participants

Reaction Steps

The crude cyclo[Arg(Tos)-Lys(Z)-Asp(OBzl)-Val-Tyr(Bzl)-Gly] (1 g) was cleaved with HF/anisole (20 ml; 9:1) at 0° C. for 1 h. The peptide resin mixture was washed with diethylether (3×20 ml). The peptide was extracted with 5 aqueous acetic acid (3×20 ml) and lyophilized. The crude material was chromatographed on a Sephadex SPC-25 column (60 cm×2.5 cm), equilibrated with 0.2M NH OAc, pH 5.25 at a flow rate of 85 ml/h with a fraction size of 10 ml. Fractions 130-153 were pooled and lyophilized to give 40 mg of material; Rf 0.32 (C); Amino acid analysis: Acid hydrolysis: Arg, 1.02; Lys, 0.98; Asp, 1.08; Val, 1.03; Tyr, 0.93; Gly, 0.95; Carboxypeptidase A hydrolysis: trace (<3 percent) of Tyr and Gly; FAB/MS MH+ =719; HPLC: C18 -μBondapak, 2 ml/min, 214 nm, 10 percent methanol/0.02M KH2PO4, pH 3.5, retention time 60.26 min.

Provenance & Evidence