The structure of the title compound, C32H51NO6, was determined from 62-year-old crystals at room temperature and refined with 100 K data in a monoclinic (C2) space group. This compound with a triterpenoid structure, now confirmed by this study, played an important role in the determination of the structure of lanosterol. The mol-ecules pack in linear O-H⋯O hydrogen-bonded chains along the short axis (b), while parallel chains display weak van der Waals inter-actions that explain the needle-shaped crystal morphology. The structure exhibits disorder of the flexible methyl-heptane chain at one end of the main mol-ecule with a small void around it. Crystals of the compounds were resistant to data collection for decades with the available cameras and Mo Kα radiation single-crystal diffractometer in our laboratory until a new instrument with Cu Kα radiation operating at 100 K allowed the structure to be solved and refined.
Keywords: crystal structure; disorder; lanosterol; old crystals; terpenoid.