Reanalysis of delcosine and several of its derivatives shows that the most likely empirical formula is C24H39O7N. Delcosine has been shown to be identical with Goodson's base C. Acetylation produces monoacetyldelcosine, identical with Goodson's naturally occurring base B. It has been possible to prepare two isomeric diacetyl derivatives, one of which has been reported previously, and a further acetylated compound also reported previously which seems to have lost the elements of water. A dipropionyldelcosine is also described. The base contains three methoxyls and four hydroxyls, only two of which are acetylated readily.