Studies on Peptides. CXIX. Synthesis of Growth Hormone Releasing Factor (hpGRF-40-OH)

Abstract

The tetracontapeptide corresponding to the entrie amino acid sequence of growth hormone releasing factor (hpGRF-40-OH) was synthesized by fragment condensation in solution, followed by deprotection with 1M trifluoromethanesulfonic acid-thioanisole in trifluoroacetic acid. In in vivo assay, synthetic hpGRF-40-OH was as active as synthetic hpGRF-44-NH₂, but in in vitro assay, the potency of synthetic hpGRF-40-OH was only 36% of that of synthetic hpGRF-44-NH₂.