Oxytocin: Crystal Date of a Seleno Analog

Abstract
The sulfur atom in position 6 of deamino-oxytocin (1-beta-mercapto-propionic acid-oxytocin) was replaced by selenium. The crystals of the resulting deamino-6-seleno-oxytocin are similar to those of the "wet" form of deamino-oxytocin, but they are stable upon prolonged exposure to air.