Steroid-cationic lipid compound and use thereof

A compound represented by formula (I)

• wherein R1 is selected from —OR4, —NR4R5, —NR4C(═O)R5, —C(═O)OR5, —OC(═O)R5, —OC(═O)OR5, —CN, a nitrogen-containing heterocyclic group, and guanidino;
• R4 and R5 are each independently selected from H, C1-9 alkyl, C2-9 alkenyl, C2-9 alkynyl, C3-8 cycloalkyl, C3-8 cycloalkenyl, and C3-8 cycloalkynyl;
• G1 is selected from a chemical bond (—), C1-9 alkylene, C2-9 alkenylene, C3-9 alkynylene, C3-8 cycloalkylene, and C3-8 cycloalkenylene;
• preferably, R1-G1- has no more than 10 contiguous carbon atoms;
• G2 and G3 are each independently selected from a chemical bond (—), C1-12 alkylene, C2-12 alkenylene, C2-12 alkynylene, C3-12 cycloalkylene, C3-12 cycloalkenylene, C3-12 cycloalkynylene, and C6-12 arylene;
• L1 and L2 are each independently selected from a chemical bond (—), —O—, —S—, —O(C═O)O—, —(C═O)NRa—, —NRa(C═O)—, —O(C═O)—, —(C═O)O—, —S—S—, —S(O)x—, —OS(O)xO—, —C(═O)S—, —SC(═O)—, —NRaC(═O)NRb—, —OC(═O)NRa—, —NRaC(═O)O—, —OC(═O)S—, —SC(═O)O—, —P(O)(ORa)O—, —OP(O)(ORa)O—, and C1-12 alkylene, or a combination thereof;
• x is selected from 0, 1, and 2;
• Ra and Rb are each independently selected from H, C1-12 alkyl, C2-12 alkenyl, and C2-12 alkyne;
• R2 is selected from a naturally occurring or non-naturally occurring steroid;
• R3 is selected from a naturally occurring or non-naturally occurring steroid, C6-24 alkyl, C6-24 alkenyl, C6-24 alkyne, and C6-24 alkoxy.