Two new 9,11-secosterols from the marine sponge Spongia officinalis. Synthesis of 9,11-seco-3β,6α,11-trihydroxy-5α-cholest-7-en-9-one

Article abstract of DOI:10.1016/0039-128X(92)90054-D

Two new 9,11-secosterol, 9,11-seco-3β,6α,11-trihydroxy-5α-cholest-7-en-9-one (2) and 9,11-seco-3β,6α,11-trihydroxy-24-methylene-5α-cholest-7-en-9-one (3), have been isolated from the marine sponge Spongia officinalis and their structures elucidated by analysis of spectral data including 1H nuclear magnetic resonance correlation spectroscopy (COSY) experiments.Partial synthesis of 2 starting from 3β,6α-dihydroxy-9-oxo-9,11-seco-5α-cholest-7-en-11-al (1) confirmed the structure assignment. Keywords: sterols; 9,11-secosterols; 9,11-seco-3β,6α,11-trihydroxy-5α-cholest-7-en-9-one; 9,11-seco-3β,6α,11-trihydroxy-24-methylene-5α-cholest-7-en-9-one; synthesis; 1H nuclear magnetic resonance; 13C nuclear magnetic resonance; two-dimensional nuclear magnetic resonance correlation spectroscopy