Sulfated steroids: ptilosteroids A-C and ptilosaponosides A and B from the Solomon Islands marine sponge Ptilocaulis spiculifer.
Résumé
Three new pregnanes, ptilosteroid A (1), ptilosteroid B (2), and ptilosteroid C (3), and two new pregnane glycosides, ptilosaponoside A (4) and ptilosaponoside B (5), were isolated from the marine sponge Ptilocaulis spiculifer 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.