A 19-norbufalin derivative compound of formula (I): ##STR00001## wherein the R groups are as defined by the present specification. The compounds are Na.sup.+K.sup.--ATPase inhibitors and can be used in the treatment of cardiac and/or vascular malfunction, renal malfunction, as digoxin antagonists, for treatment of CNS disorders and for the treatment of malignant and proliferative cell diseases.