Scheme 4. (a) Sequences of synthetically prepared human insulin variant. (b) Chemical synthesis of human insulin variant. (c) Course of KAHA ligation monitored by analytical RP-HPLC. (d) Course of the peptide folding and O → N shift. Bottom RP-HPLC trace of purified folding precursor (14). Middle RP-HPLC trace after 12 hours folding and 4 hours basic incubation. Top RP-HPLC trace of purified folded peptide (15). (e) RP-HPLC of purified human insulin variant (16). (f) HR MS trace of purified human insulin variant (16). (g) CD spectra of 16.
