Table 1. Antiproliferative Activity (IC₅₀ in μM) with Standard Deviation and Values of the Selectivity Index (SI) of 1,2,3-Triazole Derivatives of Ironomycin, Measured at 72 h in HMLER CD24^low/CD44^high, HMLER CD24^high/CD44^low, MCF7, and MCF10A Cells^a.

	HMLER CD24low/CD44high	HMLER CD24high/CD44low	SI (HMLER)	MCF7	MCF10A
ironomycin	0.13 ± 0.01	1.75 ± 0.06	13.5	0.41 ± 0.07	0.12 ± 0.02
1	3.34 ± 0.08	10.31 ± 1.00	3.1	2.91 ± 0.54	6.06 ± 0.40
2	0.03 ± 0.004	0.98 ± 0.30	32.7	0.10 ± 0.05	2.51 ± 0.71
3	0.03 ± 0.002	0.45 ± 0.05	15.0	0.10 ± 0.05	1.26 ± 0.67
4	0.04 ± 0.01	0.74 ± 0.17	18.5	0.43 ± 0.02	2.35 ± 1.16
5	0.46 ± 0.03	2.42 ± 0.20	5.3	3.02 ± 0.52	12.09 ± 2.00
6	10.85 ± 0.90	25.26 ± 2.80	2.3	>12.5	>12.5
7	8.83 ± 1.10	23.71 ± 0.90	2.7	2.48 ± 0.41	>12.5
8	0.09 ± 0.02	1.13 ± 0.30	12.6	0.49 ± 0.10	0.53 ± 0.23
9	9.29 ± 1.40	27.95 ± 2.90	3.0	12.67 ± 0.18	11.98 ± 1.08

^aSelectivity index (SI) was defined as IC₅₀(HMLER CD24^high/CD44^low)/IC₅₀(HMLER CD24^low/CD44^high). Each IC₅₀ value was determined in biological triplicate (three independent biological experiments), and each triplicate was determined in at least technical duplicate.