Table 1.

Anti-HIV-1 efficacy and cytotoxicity of 4′C-methyl- and -ethyl-2′-deoxyadenosine

Compound and cell line	EC50 (nM)	CC50 (μM)	Selective indexa
4′-C-Me-2′-dA
HOS	63 ± 7	59 ± 5	936
TZM-bl	69 ± 4	169 ± 22	2,550
4′-C-Et-2′-dA
HOS	221 ± 3	369 ± 22	1,669
TZM-bl	184 ± 20	204 ± 28	1,109

^aSelective index = CC₅₀/EC₅₀.