Novel ring B abeo-sterols as growth inhibitors of Mycobacterium tuberculosis isolated from a Caribbean Sea sponge, Svenzea zeai

Assay-guided fractionation of a moderately strong anti-tubercular extract obtained from the Caribbean Sea sponge Svenzea zeai afforded two novel 5(6 → 7)abeo-sterols, named parguesterols A (1) and B (2), as its active components. Their structures were elucidated on the basis of extensive spectroscopic analysis.

A chemical investigation on the hexane-soluble fractions from the crude extract of the marine sponge Svenzea zeai afforded two novel steroid derivatives with strong anti-tubercular properties.