Lipid composition

A lipid composition comprising:

• a compound represented by Formula (1);
• a lipid represented by Formula (2) or a salt of the lipid;
• a neutral lipid;
• a lipid having a nonionic hydrophilic polymer;
• and
• a nucleic acid,
• in Formula (1),
• R101 represents
• * represents a bonding position, R201 represents a chain-like hydrocarbon group having 7 to 18 carbon atoms,
• represents a single bond or a double bond,
• R102 represents
• (i) a hydrogen atom,
• (ii) a hydrocarbon group having 1 to 4 carbon atoms, which may be substituted with one or more substituents selected from OH, SH, COOH, NR106R107, N(R108)C(O)R109, or CF3,
• (iii) C(O)R103, or
• (iv) C(O)NR104R105,
• R103 represents a hydrocarbon group having 1 to 4 carbon atoms, which may be substituted with one or more substituents selected from OH, SH, COOH, NR110R111, N(R112)C(O)R113, or CF3,
• R104 and R105 each independently represent a hydrogen atom, or a hydrocarbon group having 1 to 4 carbon atoms, which may be substituted with one or more substituents selected from OH, SH, COOH, NR110R111, N(R112)C(O)R113, or CF3,
• R106, R107, R108 and R109 each independently represent a hydrogen atom, or a hydrocarbon group having 1 to 4 carbon atoms, which may be substituted with one or more substituents selected from OH, SH, COOH, NR110R111, N(R112)C(O)R113, or CF3, and
• R110, R111, R112, and R113 each independently represent a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms, which may be substituted with one or more substituents selected from OH or SH,
• in Formula (2), X represents —NR1— or —O—,
• R1 represents a hydrogen atom, a hydrocarbon group having 6 to 24 carbon atoms, or a group represented by R21-L1-R22—, where R21 represents a hydrocarbon group having 1 to 24 carbon atoms, L1 represents —O(CO)O—, —O(CO)—, —(CO)O—, —O—, or
• and R22 represents a divalent hydrocarbon linking group having 1 to 18 carbon atoms,
• R2 and R3 each independently represent a hydrogen atom, a hydrocarbon group having 3 to 24 carbon atoms, or a group represented by R31-L2-R32—, where R31 represents a hydrocarbon group having 1 to 24 carbon atoms, L2 represents —O(CO)O—, —O(CO)—, —(CO)O—, —O—, or
• and R32 represents a divalent hydrocarbon linking group having 1 to 18 carbon atoms,
• R4, R5, R6, R7, R8, R9, R10, R11, and R12 each independently represent a hydrogen atom or an alkyl group having 1 to 18 carbon atoms which may be substituted,
• in any one or more pairs of groups among R4 and R5, R10 and R5, R5 and R12, R4 and R6, R5 and R6, R6 and R7, R6 and R10, R12 and R7, and R7 and R8, the groups may be linked to each other to form a 4- to 7-membered ring which may contain an O atom,
• a substituent on the alkyl group having 1 to 18 carbon atoms which may be substituted is a hydroxyl group, a carboxyl group, an amino group represented by —NR45R46, a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a group represented by —O(CO)O—R41, —O(CO)—R42, —(CO)O—R43, or —O—R44, where R41, R42, R43, R44, R45, and R46 each independently represent a hydrocarbon group having 1 to 18 carbon atoms,
• a substituent on the substituted or unsubstituted aryl group and on the substituted or unsubstituted heteroaryl group is an alkyl group having 1 to 18 carbon atoms, a hydroxyl group, a carboxyl group, an amino group represented by —NR45R46, or a group represented by —O(CO)O—R41, —O(CO)—R42, —(CO)O—R43, or —O—R44, where R41, R42, R43, R44, R45, and R46 each independently represent a hydrocarbon group having 1 to 18 carbon atoms, and
• a, b, c, and d each independently represent an integer of 0 to 3, provided that a+b is 1 or more, and c+d is 1 or more.