Synthesis, biological activity and conformational study of a somatostatin hexapeptide analogue containing a reduced peptide bond.
The cyclic hexapeptide analogue of somatostatin, c[Phe psi(CH2-N)Pro-Phe-D-Trp-Lys-Thr], was prepared by solid-phase synthesis of the linear precursor, followed by cyclization using diphenylphosphoryl azide. The inhibition of GH release, as well as receptor affinity, is greatly decreased. Conformational analysis by NMR in DMSO/H2O (1/1) revealed the presence of a type II' beta-turn in the core tetrapeptide region and a delta-turn over the reduced peptide bond.
Delaet
N G
NG
Vrije Universiteit Brussel.
Verheyden
P
P
Velkeniers
B
B
Hooghe-Peters
E L
EL
Bruns
C
C
Tourwé
D
D
Van Binst
G
G
D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry*; D010084:Oxidation-Reduction; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism; D011487:Protein Conformation; D051381:Rats; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000378:metabolism
D009842:Oligopeptides; D010456:Peptides, Cyclic; D013004:Somatostatin