New delta 8- and delta 8(14)-5 alpha,6 alpha-epoxysterols from the marine sponge Spongia officinalis.

Six new delta 8- and delta 8(14)-5 alpha,6 alpha-epoxysterols (1-6) have been isolated from a collection of the Mediterranean sponge Spongia officinalis. The structures of the new metabolites, isolated as diacetate derivatives, have been determined by spectral analyses and an x-ray diffraction experiment performed on the diacetyl derivative of 1.