4-(4-Hy-droxy-phenyl)-2,2,4-trimethyl-7,8-benzo-thia-chroman, a fused-ring counterpart of -Dianin's compound.

The title compound, CHOS [systematic name: 4-(1,3,3-trimethyl-2,3-di-hydro-1-4-thia-phenanthren-1-yl)phenol], crystallizes unsolvated from nitro-methane as colourless prisms (m.p. 425-427 K) in the polar monoclinic space group with ' = 2 (mol-ecules and ). Both independent mol-ecules possess a very similar conformation, this referring to the juxtaposition of the 4-hy-droxy-phenyl substituent with respect to the -related methyl group. In the crystal, mol-ecule is linked to mol-ecule by an O-H⋯O hydrogen bond. In turn, mol-ecule exhibits a weak O-H⋯π inter-action with the phenolic group of mol-ecule related by -glide symmetry. Together, these lead to [100] chains.