Drupella fragum is a species of sea snail, a marine gastropod mollusk in the family Muricidae, the murex snails or rock snails.
Powerful antioxidants were found in the midgut gland of Drupella fragum; which were brominated hydroxyindoles; the main compound isolated was 6-bromo-5-hydroxyindole and its positional isomers, such as 6-bromo-4,5-dihydroxyindole and 6-bromo-4,7-dihydroxyindole. Among other compounds, 6-methoxy-4,7-indoloquinone and 5-methyl-4,7-indoloquinone were also isolated.
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