Bufadienolides with cytotoxic activity from the eggs of Bufo bufo gargarizans

Seven bufadienolides (1–7) were isolated from the eggs of toad Bufo bufo gargarizans. Their chemical structures were identified on the basis of various spectroscopic methods, including NMR and HRESIMS. These compounds were tested for their cytotoxic effects against human lung cancer cell line A549, human liver cancer cell line BEL-7402 and human gastric cancer cell line BGC-823. All of them exhibited potent cytotoxic activity.