| abstract |
The present invention provides a cationic lipid that can be used for cytoplasmic nucleic acid delivery. The cationic lipid of the present invention is, for example, a compound represented by the following formula (1a) or a pharmaceutically acceptable salt thereof. [In the formula, L 1 and L 2 each independently represent an alkylene group having 3 to 10 carbon atoms, and R 1 and R 2 each independently represent an alkyl group having 4 to 22 carbon atoms or an alkenyl group having 4 to 22 carbon atoms, X 1 represents a single bond or -CO-O-, and ring P represents any one of the following formulae (P-1) to (P-5)] [In the formula, R 3 represents an alkyl group having 1 to 3 carbon atoms]. |