[Chemical constituents of bufadienolides in cinobufacino injection].

Cinobufacino injection is purified from water extraction of the skin of Bufo bufo gargarizans, which has been widely used for various cancers in clinic with significant anti-tumor effects. Bufadienolides were regarded as the main active constituents of cinobufacino injection in previous reports. In present study, 6 bufadienolides were isolated and purified from Cinobufacino injection. Their structures were identified as 3-epi-ψ-bufarenogin (1), ψ-bufarenogin (2), 3-epi-arenobufagin (3), arenobufagin (4), 3-epi-gamabufotalin (5), and 3-oxo-arenobufagin (6), separately. Among them, 1 and 3 were new compounds, 5 and 6 were new natural products. Compounds 1, 2 and compounds 3, 4 were two pairs configuration isomers at C-3, separately.