Study of pituitary hormone analogs for their inhibitory properties and

1294 Journal of Medicinal Chemistry, 1974, Vol. 17, No 12

Grronka. Glas.c, Schwartz, Walter

Study of Pituitary Hormone Analogs for Their Inhibitory Properties and Resistance to Carboxamidopeptidases: [9-~-Froline]oxytocin,[ 9 - -Glutamic ~ acidloxytocin, and [8-L L y sine,9-glycine methylamide]oxytocint

-

Z. Grzonka, J. D. Glass, I. L. Schwartz, and Roderich Walter* Department of Physiology and Biophysics, Mount Sinai School of Medicine of the City University of New York, New York, New York 10029, and Medical Research Center, Brookhaven National Laboratory, Upton, New York 11973 Received April 24, 1974

Syntheses, biological activities, and preliminary enzyme studies are reported for two oxytocin analogs in which the glycine residue in position 9 is replaced by glutamic acid or proline. Biological and enzymological studies of [8-lysine,g-glycine methylamide]oxytocin are also reported. [g-Glutamicacidloxytocin was found to possess 0.05 f 0.009 U/mg of oxytocic activity,