Arenobufagin and gamabufotalin from the venom of the Central Asian green toadBufo viridis. Introduction, structural—functional features

Two bufodienolides have been isolated in the individual form from the Central Asian green toadBufo viridis for the first time. It has been established by1H NMR, mass spectrometry, and x-ray structural analysis that these compounds are gamabufotalin (3β, 11α, 14-trihydroxy-5β, 14s-bufa-20,22-dienolide) and a crystalline modification of arenobufagin (3β, 11α, 14-trihydroxy-12-oxo-5β, 14β-bufa-20,22-dienolide). The biological activity of Bakagin — the total bufadienolides of the venom ofB. viridis, consisting predominantly of the compounds named — has been studied. The promising nature of a further study of Bakagin as a cardiotonic drug has been shown.