Sulfated Steroids: Ptilosteroids A−C and Ptilosaponosides A and B from the Solomon Islands Marine Sponge <i>Ptilocaulis spiculifer</i>

Three new pregnanes, ptilosteroid A (<b>1)</b>, ptilosteroid B (<b>2</b>), and ptilosteroid C (<b>3</b>), and two new pregnane glycosides, ptilosaponoside A (<b>4</b>) and ptilosaponoside B (<b>5</b>), were isolated from the marine sponge <i>Ptilocaulis spiculifer</i> collected in the Solomon Islands. The structures were determined by spectroscopic methods. Biological tests of these compounds showed that they are not cytotoxic against KB cells.