Compound having alkadienyl group as side chain, and liquid crystal composition using same

A compound represented by the general formula (1)

• wherein R1 is an alkadienyl group having 4 to 10 carbon atoms in which at least one hydrogen atom may be substituted by a fluorine atom, a chlorine atom or a cyano group;
• R2 is an alkenyl group having 2 to 10 carbon atoms in which at least one hydrogen atom may be substituted by a fluorine atom, a chlorine atom or a cyano group;
• one or more non-adjacent methylene groups (—CH2—) in the alkadienyl group or the alkenyl group may be replaced by —O—, —CH═CH— or —C≡C—;
• rings A1, A2, A3 and A4 are each independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, pyridine-2,5-diyl or pyrimidine-2,5-diyl in which at least one hydrogen atom may be substituted by a halogen atom;
• Z1, Z2 and Z3 are each independently a single bond, —CH2CH2—, —CH═CH—, —C≡C—, —CH2O—, —OCH2—, —(CH2)4—, —(CH2)3—O—, —O—(CH2)3—, —(CH2)2—CH═CH—, —CH═CH—(CH2)2—, —CF2O—, —OCF2—, —CR═CH—, —CH═CR— or —CF═CF—, and R is an alkyl group having 1 to 5 carbon atoms;
• p and q are each independently 0 or 1.