title: Minor and trace sterols in marine invertebrates  XVII. (24R)-24,26-Dimethylcholesta-5,26-dien-3 beta-OL, a new sterol from the sponge Petrosia ficiformis.
abstract: More than thirty monohydroxy sterols were detected in the marine sponge Petrosia ficiformis, ranging from the ubiquitous 24-norcholesta-5,22-dien-3 beta-ol to the C30 sterol, 24-propylidenecholesterol. A new minor sterol was isolated and shown by spectral analysis and comparison with a synthetic sample to be (24R)-24,26-dimethylcholesta-5,26-dien-3 beta-ol [26(29)-dehydroaplysterol] (12).
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D002775:Cholestadienols / Q000032:analysis*; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D003521:Cyclopropanes / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011161:Porifera / Q000032:analysis*; D013261:Sterols / Q000032:analysis*
chemical_list: C026360:24,26-dimethylcholesta-5,26-dien-3 beta-ol (24R); D002775:Cholestadienols; D003521:Cyclopropanes; D013261:Sterols; C026361:petrosterol