| abstract |
A compound is of formula (I), in which: A?1 to A4, E1 and E2¿ each independently represent hydrogen or an optionally-substituted hydrocarbon group; B?1 and B2¿ each independently represent a single bond, an oxygen atom or an optionally-substituted hydrocarbon group; MG?1 and MG2¿ each independently represent an optionally-substituted ring system; CG is a divalent or polyvalent chiral group. The optically active compound may be used as a doping agent for liquid crystals for a wide range of applications including solid state cholesteric filters for projection displays, circular polarisers, optical filters, etc. |