Fun, H.-K.Liew, W.-C.Rai, S.Shetty, P.Isloor, A.M.2026-02-052009Acta Crystallographica Section E: Structure Reports Online, 2009, 65, 8, pp. o1999-o200016005368https://doi.org/10.1107/S1600536809029031https://idr.nitk.ac.in/handle/123456789/27606The title compound, C<inf>12</inf>H<inf>19</inf>IO<inf>5</inf>, is the ortho-rhom-bic polymorph of a previously reported monoclinic form [Krajewski et al. (1987). Bull. Pol. Acad. Sci. Chem. 35, 91-102]. The dihedral angles between the six-membered ring and the two five-membered rings are 67.66 (14) and 71.79 (13)°, whereas the dihedral angle between the five-membered rings is 74.41 (12)°, indicating that all three rings are twisted from each other. The six-membered ring has a twist-boat conformation while both of the five-membered rings have envelope conformations. The crystal structure is stabilized by a network of C - H?O contacts linking the mol-ecules into a two-dimensional array parallel to the ab plane. © 2009 Fun et al.