Hellebrin (CAS 13289-18-4)

Hellebrin is a cardiotonic glycoside which presents a bufadienolide-steroid structure. Besides ouabain, from the class of cardenolides hellebrin is the second unique water soluble cardiotonic glycoside. Extremely potent inhibitor of Na⁺/K⁺-ATPase (sodium pump) blocking the active efflux of Na⁺ and reuptake of K⁺ of this membrane enzyme. Shows a positive inotropic effect by increasing the intracellular Ca²⁺ concentration. Hellebrin is a strong immunosuppressor inhibiting T cell activity with much higher potency than cortisol or cyclosporin A Induces caspase-dependent apoptosis.

References

Über Hellebrin, ein krystallisiertes Glykosid aus Radix Hellebori nigri: W. Karrer; Helv. Chim. Acta 26, 1353 (1943) The structure of hellebrin: P. Muhr, et al.; Liebigs Ann. Org. Bioorg. Chem. 2, 443 (1995) In search of ideal inotropic steroids: recent progress: K.R. Repke, et al.; Prog. Drug Res. 47, 9 (1996) Exquisitely small amounts of nonglucocorticoid natural steroids suppress the human allogeneic T-cell response: P. Terness, et al.; Transplant Proc. 33, 547 (2001) Apoptosis-mediated selective killing of malignant cells by cardiac steroids: maintenance of cytotoxicity and loss of cardiac activity of chemically modified derivatives: D. Daniel, et al.; Int. Immunopharmacol. 3, 1791 (2003)