New Discorhabdin\nD Analogues from <i>Latrunculia</i> spp. Sponges

Chemical profiles of <i>Latrunculia kaakaariki</i> and <i>Latrunculia brevis</i> were investigated, resulting\nin the isolation\nof five new discorhabdin D derivatives <b>1</b> and <b>3</b>–<b>6</b>. Their planar structures were solved by combination\nof NMR and HR-MS, while <i>J</i>-based configurational analysis,\ncomputational techniques, and semisynthetic methods were used for\nthe establishment of their absolute configurations. New natural products\nwere tested for their growth inhibitory activity against the NCI-60\nhuman tumor cell line panel, and two compounds <b>5</b> and <b>6</b> showed low micromolar potency.