Anti-Helicobacter, Antitubercular and Cytotoxic Activities of Scalaranes from the Red Sea Sponge Hyrtios erectus †.

The Red Sea specimen of the marine sponge <italic>Hyrtios erectus</italic> (order Dictyoceratida) was found to contain scalarane-type sesterterpenes. 12-<italic>O</italic>-deacetyl-12,19-di-<italic>epi</italic>-scalarin (<bold>14</bold>), a new scalarane sesterterpenoid, along with fourteen previously-reported scalarane-type sesterterpenes (<bold>1</bold>–<bold>13</bold> and <bold>15</bold>) have been isolated. The chemical structures of the isolated compounds were elucidated on the basis of detailed 1D and 2D NMR spectral data and mass spectroscopy, as well as by comparison with reported data. The anti-<italic>Helicobacter pylori</italic>, antitubercular and cytotoxic activities of all fifteen compounds were evaluated to reveal the potency of Compounds <bold>1</bold>, <bold>2</bold>, <bold>3</bold>, <bold>4</bold>, <bold>6</bold>, <bold>7</bold> and <bold>10</bold>. Amongst these, Compounds <bold>1</bold>, <bold>3</bold>, <bold>4</bold>, <bold>6</bold> and <bold>10</bold> displayed a promising bioactivity profile, possessing potent activities in the antitubercular and anti-<italic>H. pylori</italic> bioassay. Compounds <bold>2</bold> and <bold>7</bold> showed the most promising cytotoxic profile, while Compounds <bold>1</bold> and <bold>10</bold> showed a moderate cytotoxic profile against MCF-7, HCT-116 and HepG2 cell lines. [ABSTRACT FROM AUTHOR]