PURPOSE: To obtain the subject new compound, having a low crystallization temperature and useful as a material for a liquid crystal in the field of optoelectronics without causing the phase separation even by adding thereof into a liquid crystal composition for improving the responsiveness of the liquid crystal composition to the electric field, in preparing the ferroelectric liquid crystal composition.

CONSTITUTION: This compound is expressed by formula I [R1 is biphenyl, formula II to IV, etc.; H in the aromatic ring may be substituted with F; R2 is a 4-20 optically inactive alkyl; (l) and (m) are each 2-20; (n) is 1-20; Y is single bond, 0, COO or OCO], e.g. a compound expressed by formula V. The compound expressed by formula V is obtained by adding DMF to diethylacetic acid and tetramethylammonium hydroxide pentahydrate and reacting a compound expressed by formula VI therewith.