| 摘要 |
Derivatives of growth hormone releasing factor GRF(1-29)NH2 and analogs thereof, are prepared by reacting a substrate component of the formula GRF'-Met-Ser-X, wherein GRF' denominates the native GRF(1-26) sequence or analogs thereof including GRF(n-26) fragments, where n is from 1 to 8, and X is an acyclic alpha -amino carboxylic acid residue having an uncharged hydrophilic side chain of at least the size of a methyl group, preferably Ala, Thr, Ser, Asn or Gln, with H-Arg-NH2 as mucleophile component in the presence of an L-specific serine or thiolcarboxypeptidase enzyme from yeast or of animal, vegetable or other microbial origin, preferably CPD-Y from yeast, in an aqueous solution or dispersion having a pH of from 6 to 9, and if necessary coupling the desired N-terminal (1-(n-1)) fragment chemically or enzymatically. GRF-related peptides of the formula GRF"-Met-Ser-X, wherein GRF" denominates the native GRF(1-26) sequence, wherein from 1 to 4 amino acid residues may be replaced or deleted or the des- alpha -NH2 derivatives thereof, and X is as described above and useful intermediates. The process enables a selective transpeptidation leading to biologically active GRF-related amides in good yields. |
