The finding of 9-β-D-arabinosyladenine (araA) and of its 3′-O-acetyl derivative in the gorgonianEunicella cavolini is reported. Up to now these substances have not been described as natural compounds but they are well known as potent synthetic antiviral agents. The isolation of spongouridine (araU), 1-β-D-arabinofuranosyluracil from the same source is also described.