Chemical composition and biological activity of total bufadienolides from the Central-Asian Bufo viridis toad venom

The chemical composition of bufadienolides isolated from the venom of Bufo viridis green toad occurring in Central Asia was determined and their biological properties were studied. Six individual bufadienolides were isolated by reverse-phase chromatography on a Lichrosorb RP-8 (10 µ) column in amounts sufficient for qualitative analysis. Two of these were previously identified as arenobufagin and gamabufotalin by NMR spectroscopy and x-ray diffraction methods. The chemical structures of four other bufadienolides are now established by NMR spectroscopy and HPLC. These compounds have been identified as telocinobufagin (3β,5β,14β-trihydroxybufa-20,22-dienolide), marinobufagin (3β, 5β-hydroxy-14,15β-epoxybufa-20,22-dienolide), bufarenogin (3β,12β,14β-hydroxybufa-20,22-dienolide), and bufalin (3β,14β-hydroxybufa-20,22-dienolide).