Compound having four polymerizable groups, liquid crystal composition and liquid crystal display device

A compound represented by formula (1):

• wherein ring A1, ring A2, ring A3 and ring A4 are independently phenylene or cyclohexylene, and in these groups at least one hydrogen may be replaced by alkyl having 1 to 10 carbons, fluorine, —CF2H or —CF3;
• Z1, Z2, Z3 and Z4 are independently a single bond or alkylene having 1 to 6 carbons, and in the alkylene at least one —CH2— may be replaced by —O—, —COO—, —CH═CH— or —C≡C—;
• L1, L2 and L3 are independently a single bond, —COO—, —CH═CH—, —CH═CH—COO—, —C(CH3)═CH—COO—, —CH═C(CH3)—COO—, —C(CH3)═C(CH3)—COO—, —C≡C—, —COCH═CH—, —C(CH3)═C(CH3)—, —CH═CH—CH2O—, —CH═CH—OCH2— or —CO—, and when any one of L1, L2 and L3 is —COO—, the rest of L1, L2 or L3 is a single bond, —CH═CH—, —CH═CH—COO—, —C(CH3)═CH—COO—, —CH═C(CH3)—COO—, —C(CH3)═C(CH3)—COO—, —C≡C—, —COCH═CH—, —C(CH3)═C(CH3)—, —CH═CH—CH2O—, —CH═CH—OCH2— or —CO—;
• s and t are independently 0 or 1, and the sum of s and t is 0, 1 or 2;
• P1, P2, P3 and P4 are independently a polymerizable group;
• and
• when L1 is a single bond and s and t are 0, an alkyl substituent at 2-position of the ring A1 and an alkyl substituent at 2-position of the ring A4 may be bonded with each other to form a ring.