ADRENOCORTICOTROPIN. 48. SYNTHESIS AND BIOLOGICAL ACTIVITY OF [15,16-D-LYSINE,17,18-D-ARGININE] -ADRENOCORTICOTROPIN-(1-19) AND AN ALL-D-RETROPEPTIDE RELATED TO THE AMINO TERMINAL OCTADECAPEPTIDE OF ADRENOCORTICOTROPIN*

The peptide [15, 16-D-lysine, 17, 18-D-arginine]-adrenocorticotropin-(1-19) and an all-D-retropeptide related to the amino terminal octadecapeptide of adrenocorticotropin have been synthesized by the solid-phase method. The nonadecapeptide was shown to possess 10-15% of the steroidogenic activity and 3% of the lipolytic activity of adrenocorticotropin-(1-19). The all-D-retropeptide showed no activity and exhibited no inhibitory activity in steroidogenesis and lipolysis.