t-Butyldimethylsilyl Cinobufagine-d3 is a labelled analogue of t-Butyldimethylsilyl Cinobufagine (B809503). t-Butyldimethylsilyl Cinobufagine-d3 is an intermediate in synthesizing Cinobufagine-d3 (C475502), a major component of cinobufacini (huachansu), is an important cardenolidal steroid. Cinobufagine was shown to exhibit potent anti-cancer effects.