Table 1. Cytotoxic activity IC₅₀* of the triphenylphosphonium betulinic and ursolic acid derivatives against the cancer cells TET21N and MCF-7.

Test compound	TET21N	MCF-7
6	1.26 ± 0.18	0.80 ± 0.08
7	0.98 ± 0.11	0.85 ± 0.09
8	1.28 ± 0.18	1.51 ± 0.13
9	0.74 ± 0.14	0.70 ± 0.11
10	0.95 ± 0.15	2.31 ± 0.09
14	4.4 ± 0.34	2.76 ± 0.21
15	0.81 ± 0.08	1.59 ± 0.11
16	1.18 ± 0.16	3.90 ± 0.06
BA-DCA	4.9 ± 0.2	15.89 ± 0.19
UA-DCA	>10	>20
BA	—	>25