The synthesis of CCK - 4 (H - Trp- Met- Asp- Phe- NH2 ) by using enzym es exclusively was described.As protection group for the amino group we used the Phenylacetyl group (Phac) which had been cleaved at the end of ...The synthesis of CCK - 4 (H - Trp- Met- Asp- Phe- NH2 ) by using enzym es exclusively was described.As protection group for the amino group we used the Phenylacetyl group (Phac) which had been cleaved at the end of the synthesis with Penicillin G Amidase (PGA ) without affecting the peptide bonds.Thus,beginning with Phac- Trp- OH we had successfully synthesized the target peptide with following4 enzymes,α- Chym otrypsin,Papain,Therm olysin and PGA in four reac- tion steps.All reactions were carried out in aqueous buffer in reasonable yields(>6 5 % ) .FAB- MS or FD- MS verified the correct molecular mass of all peptides.展开更多
文摘The synthesis of CCK - 4 (H - Trp- Met- Asp- Phe- NH2 ) by using enzym es exclusively was described.As protection group for the amino group we used the Phenylacetyl group (Phac) which had been cleaved at the end of the synthesis with Penicillin G Amidase (PGA ) without affecting the peptide bonds.Thus,beginning with Phac- Trp- OH we had successfully synthesized the target peptide with following4 enzymes,α- Chym otrypsin,Papain,Therm olysin and PGA in four reac- tion steps.All reactions were carried out in aqueous buffer in reasonable yields(>6 5 % ) .FAB- MS or FD- MS verified the correct molecular mass of all peptides.
