Thermal Synthesis of Polypeptides from N-Butyloxycarbonyl Oligopeptides Containing Aspartyl Residue at C-Terminus

Figure 7

Gel permeation chromatograms of the reaction mixtures of Boc-Gly-L-Asp at 130°C for varying reaction times: (a) 1 h; (b) 2 h; (c) 4 h; (d) 8 h; (e) 16 h; and (f) 24 h. Solid phase: Sephadex G-25F. Eluate: 0.5 M acetic acid. Volume per test tube: 3 mL. fa: ninhydrin-negative, higher molecular weight fractions; fb: ninhydrin-positive lower molecular weight fractions.

(a)

(b)

(c)

(d)

(e)

(f)