Abstract: The present invention provides, a cationic lipid represented by the formula (1) (wherein each symbol is as defined in the specification), a lipid membrane structure using the aforementioned cationic lipid, a nucleic acid-introducing agent using the aforementioned cationic lipid, and a method for introducing a nucleic acid by using the aforementioned nucleic acid-introducing agent.

Abstract: A lyophilized composition capable of encapsulating any nucleic acid with high efficiency and easily is provided. A lyophilized composition of lipid nanoparticles not containing a nucleic acid but containing an ionic lipid, a sterol, a PEG lipid, an acidic buffer component that shows a buffering action at pH 1-6, and a cryoprotectant, wherein a weight ratio of the cryoprotectant and a total lipid is 10:1-1000:1.

Abstract: The present invention provides an O/W type emulsion having a volume median diameter of not more than 100 nm and containing a compound represented by the formula (1) wherein Xa and Xb are each independently X1, X2 or a 1,4-piperazinediyl group; s is 1 or 2, R4 is an alkyl group having 1-6 carbon atoms, na and nb are each independently 0 or 1, R1a, R1b, R2a and R2b are each independently an alkylene group having 1-6 carbon atoms, Ya and Yb are each independently an ester bond, or the like, and R3a and R3b are each independently a liposoluble vitamin residue or the like.

Abstract: The invention provides a cationic lipid, a lipid membrane structure containing same, and use thereof. The cationic lipid is represented by the formula (1) wherein R1a, R1b, R2a, R2b, R3a, R3b, Xa, Xb, Yb, Za, and Zb are as defined in the specification.

Abstract: A degradable polyethylene glycol derivative represented by formula (1). R1, R2, and R4 represent each independently a hydrogen atom or a hydrocarbon group having from 1 to 6 carbon atoms, and at least one of R1, R2, R3 and R4 is the hydrocarbon group; P1 is a straight-chain or branched polyethylene glycol chain having a number of ethylene glycol units of 3 or more; P2 is a straight-chain polyethylene glycol chain having a number of ethylene glycol units of 3 or more; w is an integer of 1 to 8; u is an integer of 1 to 10; X1 is a chemically reactive functional group; and Z1, Z2 and Z3 are each independently a selected divalent spacer.

Abstract: The invention provides a cationic lipid, a lipid membrane structure containing same, and use thereof. The cationic lipid is represented by the formula (1) wherein R1a, R1b, R2a, R2b, R3a, R3b, Xa, Xb, Ya, Yb, Za, and Zb are as defined in the specification.

Abstract: To provide a degradable polyethylene glycol derivative in which polyethylene glycol chains are linked by a disulfide linker capable of accurately controlling the degradation rate under different reductive environments in the living body, and whose division rate into a polyethylene glycol chain of low molecular weight in the living body is able to be accurately controlled. A degradable polyethylene glycol derivative represented by formula (1). R1, R2, R3 and R4 represent each independently a hydrogen atom or a hydrocarbon group having from 1 to 6 carbon atoms, and at least one of R1, R2, R3 and R4 is the hydrocarbon group; P1 is a straight-chain or branched polyethylene glycol chain having a number of ethylene glycol units of 3 or more; P2 is a straight-chain polyethylene glycol chain having a number of ethylene glycol units of 3 or more; w is an integer of 1 to 8; u is an integer of 1 to 10; X1 is a chemically reactive functional group; and Z1, Z2 and Z3 are each independently a selected divalent spacer.

Abstract: The present invention aims to provide a cationic lipid that can be used as a nucleic acid delivery carrier, a lipid membrane structure using a cationic lipid, a nucleic acid-introducing agent using a cationic lipid, and a method of achieving nucleic acid introduction by using a nucleic acid-introducing agent containing a cationic lipid. A lipid membrane structure containing a cationic lipid represented by the formula (1) wherein each symbol is as defined in the DESCRIPTION, is superior in the stability in blood and tumor accumulation property. A nucleic acid-introducing agent using the cationic lipid can achieve high nucleic acid delivery efficiency of nucleic acid to be delivered into the cytoplasm.

Abstract: The present invention provides an O/W type emulsion having a volume median diameter of not more than 100 nm and containing a compound represented by the formula (1) wherein Xa and Xb are each independently X1, X2 or a 1,4-piperazinediyl group; s is 1 or 2, R4 is an alkyl group having 1-6 carbon atoms, na and nb are each independently 0 or 1, R1a, R1b, R2a and R2b are each independently an alkylene group having 1-6 carbon atoms, Ya and Yb are each independently an ester bond, or the like, and R3a and R3b are each independently a liposoluble vitamin residue or the like.

Abstract: The invention provides a cationic lipid capable of achieving higher intracellular delivery efficiency than conventional cationic lipids, when used as a lipid membrane structure which is a carrier for delivering functional nucleic acid. The cationic lipid is represented by the formula (1): wherein each symbol is as defined herein.

Abstract: The present invention aims to provide a cationic lipid that can be used as a nucleic acid delivery carrier, a lipid membrane structure using a cationic lipid, a nucleic acid-introducing agent using a cationic lipid, and a method of achieving nucleic acid introduction by using a nucleic acid-introducing agent containing a cationic lipid. A lipid membrane structure containing a cationic lipid represented by the formula (1) wherein each symbol is as defined in the DESCRIPTION, is superior in the stability in blood and tumor accumulation property. A nucleic acid-introducing agent using the cationic lipid can achieve high nucleic acid delivery efficiency of nucleic acid to be delivered into the cytoplasm.

Abstract: The invention provides a cationic lipid capable of achieving higher intracellular delivery efficiency than conventional cationic lipids, when used as a lipid membrane structure which is a carrier for delivering functional nucleic acid. The cationic lipid is represented by the formula (1): wherein each symbol is as defined herein.

Abstract: The present invention relates to a compound represented by the formula (1) wherein Xa and Xb are each independently X1 or X2; s is 1 or 2, R4 is an alkyl group having 1-6 carbon atoms, na and nb are each independently 0 or 1, R1a and R1b are each independently an alkylene group having 1-6 carbon atoms, R2a and R2b are each independently an alkylene group having 1-6 carbon atoms, Ya and Yb are each independently an ester bond, an amide bond, a carbamate bond, an ether bond or a urea bond, and R3a and R3b are each independently a sterol residue, a liposoluble vitamin residue or an aliphatic hydrocarbon group having 12-22 carbon atoms, and use thereof.

Abstract: In production of a cationic lipid having at least one methylene group sandwiched between adjacent two cis form double bonds in the molecule, isomerization from a cis form to a trans form is suppressed. A compound represented by the following formula (I): R1—X??(I) (in Formula, R1 represents a hydrocarbon group having at least one methylene group sandwiched between adjacent two cis form double bonds in the molecule and having the carbon number of 8 to 24 and X represents a releasing group) is reacted with (B) a compound having at least one of each of tertiary amino group and hydroxyl group in the molecule in a saturated hydrocarbon solvent having the carbon number of 5 to 10 in the presence of an alkali catalyst.

Abstract: In production of a cationic lipid having at least one methylene group sandwiched between adjacent two cis form double bonds in the molecule, isomerization from a cis form to a trans form is suppressed. A compound represented by the following formula (I): R1—X??(I) (in Formula, R1 represents a hydrocarbon group having at least one methylene group sandwiched between adjacent two cis form double bonds in the molecule and having the carbon number of 8 to 24 and X represents a releasing group) is reacted with (B) a compound having at least one of each of tertiary amino group and hydroxyl group in the molecule in a saturated hydrocarbon solvent having the carbon number of 5 to 10 in the presence of an alkali catalyst.

Abstract: The present invention relates to a compound represented by the formula (1) wherein Xa and Xb are each independently X1 or X2; s is 1 or 2, R4 is an alkyl group having 1-6 carbon atoms, na and nb are each independently 0 or 1, R1a and R1b are each independently an alkylene group having 1-6 carbon atoms, R2a and R2b are each independently an alkylene group having 1-6 carbon atoms, Ya and Yb are each independently an ester bond, an amide bond, a carbamate bond, an ether bond or a urea bond, and R3a and R3b are each independently a sterol residue, a liposoluble vitamin residue or an aliphatic hydrocarbon group having 12-22 carbon atoms, and use thereof.