Sterols in Marine Invertebrates. 32. Isolation of 3β-(Hydroxymethyl)-A-nor-5α-cholest-15-ene, the First Naturally Occurring Sterol with a 15-16 Double Bond

Article abstract of DOI:10.1021/jo00148a015

A new A-nor sterol, 3β-(hydroxymethyl)-A-nor-5α-cholest-15-ene, with an unusual unsaturation in the Δ¹⁵ position has been found in the Pacific sponge Homaxinella trachys together with ten other A-nor sterols.The structure was elucidated by 360-MHz 1H NMR, 13C NMR, and mass spectral analysis as well as by chemical interconversion and comparision with synthetic 5α-cholest-15-en-3β-ol. 13C NMR spectra of the title compound and of various 3β-(hydroxymethyl)-A-nor-5α-cholestanes were assigned as an aid in future structure elucidation of this class of sterols.