(3S,5R,8R,9S,10S,13R,14S,17R)-17-(3-furyl)-10,13-dimethyl-2,3,4,5,6,7, 8,9,11,12,15,16-dodecahydro-1H-cyclopenta[a]phenanthrene-3,14,17-triol

Rostafuroxin potently inhibits binding of endogenous ouabain to the Na⁺/K⁺ ATPase (IC₅₀ = 1.7 μM) through the Src-epidermal growth factor receptor (EGFR)-dependent signaling pathway. This blocks the ouabain-dependent increase in Na⁺/K⁺ ATPase activity. In cultured renal cells where the Na⁺/K⁺ ATPase is upregulated or has increased activity, rostafuroxin normalizes mRNA levels and Na⁺/K⁺ ATPase activity. At very low doses (1 and 10 μg/kg for 5-6 weeks) in Milan-hypertensive rats, it decreased the development of hypertension. In a Phase II clinical study, rostafuroxin did not reduce blood pressure in human patients at doses of 0.05-5.0 mg/d.

(3β,5β,14β)-21,23-Epoxy-24-Norchola-20,22-diene-3,14,17-triol is used as a receptor blocker in the treatment of hypertension.