Tritiated peptides. Part 8. Synthesis of [3,5-3H2-Tyr2]-, [4-3H-Phe7]-, and [3,5-3H2-Tyr23]-human corticotrophin
Abstract
Syntheses are described of human corticotrophin nonatriacontapeptides separately labelled with tritium in the tyrosine residues at positions 2 and 23 and in the phenylalanine residue at position 7 at specific radioactivities of 49, 25, and 31 Ci mmol–1 respectively. Labelling was by reductive deiodination of protected precursors. Evidence for the integrity of the final products is provided by amino-acid analysis, column chromatography, and bioassay, supported by chemical and enzymic analytical data.