The biosynthesis of Δ5,7-sterols in Ciocalypta sp. was studied with radiolabeled Δ5-sterol precursors. Of particular interest was the role of the tetraene, 24β-methylcholesta-5,7,22,25-tetraen-3β-ol, in the biosynthetic sequence. By examining C-24 epimeric pairs, stereospecific conversion of codisterol (but not epicodisterol) into the tetraene and ergosterol was demonstrated, which served also to establish the stereochemistry at C-24 of the natural sponge sterol. These biosynthetic steps are attributed to the sponge because of the absence of symbionts such as fungi and algae as shown by electron microscopy.
|Number of pages||6|
|Journal||Journal of Organic Chemistry|
|Publication status||Published - 1989|