Table 3.

Anti- HIV activity of terpenoid compounds from E. erythradenia

Compound	Anti HIV activity	Cytotoxicity	Therapeutic index
	IC50 (μM)a	CC50 (μM)b	TI (CC50/IC50)
1a & 1b	0.003	0.014	4.67
2	0.006	0.022	3.67
3	0.002	0.011	5.5
4	0.009	0.022	2.44
5	0.036	0.004	0.11
6	0.007	0.084	11.75
7	0.008	3.264	380.64
8	0.044	0.168	26.68
Nevirapine	< 0.064	6.74	> 105.31

^aIC₅₀ = Concentration causing 50% HIV activity inhibition.

^bCC₅₀ = Concentration causing 50% cellular cytotoxicity.