Dihydrocoumarin derivative, liquid crystal composition containing the same, and liquid crystal display device

A compound represented by the following formula (1):

• wherein
• R represents an alkyl having from 1 to 20 carbon atoms;
• and in this alkyl, any —CH2— may be replaced by —O—, —S—, —CO—, —CH═CH—, or —C≡C—;
• A1, A2, and A3 each independently represents 1,4-cyclohexylene or 1,4-phenylene;
• in the 1,4-cyclohexylene, any —CH2— may be replaced by —O—, —S—, or —CO—, and any —(CH2)2— may be replaced by —CH═CH—;
• in the 1,4-phenylene, any —CH═ may be replaced by —N═;
• and in these rings, any hydrogen may be replaced by fluorine, chlorine, —CN, —CF3, —CHF2, —CH2F, —OCF3, —OCHF2, or —OCH2F;
• Z1, Z2, and Z3 each independently represents a single bond, —(CH2)2—, —CH2O—, —OCH2—, —CF2O—, —OCF2—, —CH═CH—, —CF═CF—, —C≡C—, —(CH2)4—, —O(CH2)2O—, —(CH2)2CF2O—, —(CH2)2OCF2—, —CF2O(CH2)2—, —OCF2(CH2)2—, —CH═CH—CH2O—, or —OCH2—CH═CH—;
• X represents hydrogen, fluorine, chlorine, —CN, —CF3, —CHF2, —CH2F, —OCF3, —OCHF2—, or —OCH2F;
• G represents oxygen or sulfur;
• n and m each independently represents 0, 1, or 2;
• and
• in any one of the following (i) to (iii), R may represent hydrogen:
• (i) the total sum of n and m is 1 or 2;
• (ii) X represents fluorine, chlorine, —CN, —CF3, —CHF2, —CH2F, —OCF3, —OCHF2, or —OCH2F;
• and
• (iii) at least one of A1, A2, and A3 represents 1,4-phenylene in which any hydrogen is replaced by fluorine, chlorine, —CN, —CF3, —CHF2, —CH2F, —OCF3, —OCHF2, or —OCH2F.