Table 5.

Quinone reductase induction of compounds isolated from M. caerulea^a.

Compound	CDb	IC50c	CId
1	19.8	>40	>2.4
2	2.2	17.8	8.1
3	2.4	>40	>16.8
8	1.8	35.0	19.4
11	6.6	>40	>7.1
l-sulforaphanee	0.51	20.9	40.8

^aData are represented as CD or IC₅₀ values (µM, toward Hepa 1c1c7 cell line) and were calculated using nonlinear regression analysis with measurements performed in duplicate and representative of two independent readings in which the values generally agreed within 10%

^bThe concentration required to double quinone reductase activity

^cThe concentration that inhibits 50% cell growth

^dThe chemopreventive index (IC₅₀/CD)

^ePositive control