Abstract: A phospholipid derivative, utilizable for modification of liposomes and the like, which is a copolymer containing, as essential component units, a component unit A represented by the formula (1), a component unit B represented by the formula (2A) and/or the formula (2B), and a component unit C represented by the formula (3) [R1 and R2 represent hydrogen atom or methyl group, provided that R1 and R2 do not simultaneously represent methyl group; R3 represents a divalent hydrocarbon group having 1 to 3 carbon atoms; AO represents an oxyalkylene group having 2 to 4 carbon atoms; m represents an average molar number of the added oxyalkylene groups and is a number in the range represented as 4?m?100; R4 represents hydrogen atom, a hydrocarbon group or acyl group having 1 to 20 carbon atoms; R5CO and R6CO represent an acyl group having 8 to 24 carbon atoms; R7 represents a divalent hydrocarbon group having 2 to 4 carbon atoms; and X and Y represent hydrogen atom, an alkali metal atom, ammonium or an organic ammonium

Abstract: A phospholipid derivative represented by the following formula (1): wherein [PG]k represents a residue of polyglycerin having a polymerization degree of k, wherein k is 2 to 50, R1CO and R2CO independently represent an acyl group having 8 to 22 carbon atoms, symbol “a” independently represents an integer of 0 to 5, symbol “b” independently represents 0 or 1, M represents hydrogen atom, an alkali metal atom, an ammonium, or an organic ammonium, and k1, k2, and k3 represent numbers satisfying the following conditions: 1?k1?(k+2)/2, 0?k2, and k1+k2+k3=k+2. The phospholipid derivative is highly safe for living bodies and can be suitably utilized in drug delivery systems such as liposome, and the like.

Abstract: A phospholipid derivative represented by the formula (1) (Z represents a residue of a compound having 3 to 10 hydroxyl groups; AO represents an oxyalkylene group having 2 to 4 carbon atoms; R1CO and R2CO represent an acyl group having 8 to 22 carbon atoms; X represents hydrogen atom, an alkali metal atom, ammonium or an organic ammonium; “a” represents an integer of 0 to 4; “b” represents 0 or 1; Q represents hydrogen atom or methyl group; m represents an average number of moles of the oxyalkylene group added; and m, k1, k2, and k3 are numbers satisfying the following conditions: 3?m?200, 9?m×(k1+k2+k3)?1000, 1?k1?2, 0?k2?9 and 0?k3?9, and 3?k1+k2+k3?10), which is highly safe for living bodies, and is suitably used for solubilization and dispersion of physiologically active substances and the like, or in the fields of drug delivery systems such as liposomes and cosmetics.

Abstract: A phospholipid derivative represented by the following formula (I) wherein R1CO and R2CO independently represent an acyl group; R3 represents hydrogen atom, or a hydrocarbon group; symbol “a” represents an integer of 0 to 4; symbol “b” represents 0 or 1, provided that when a is 0, b is 0; X represents hydrogen atom, an alkali metal atom, an ammonium, or an organic ammonium; A1O and A3O represent an oxyalkylene group containing oxyethylene group, wherein the ratio of the oxyethylene group to the oxyalkylene group in A1O and A3O is 0.5 or larger in terms of a weight ratio; A2O represents an oxyalkylene group; symbols “m” and “q” represent an average molar number of added oxyalkylene groups; and symbol “n” represent an average molar number of added oxyalkylene groups; provided that m, n and q satisfy the following conditions: 5?m?600, 1?n?45, 0?q?200, 10?m+n+q?600, 0.04?n/(m+n+q), and q/(m+n+q)?0.

Abstract: A cell in which a reaction product of a substance to be modified and an amphipathic compound is non-covalently bound to a cell membrane, wherein said compound has the following features: (1) having one or more aliphatic hydrocarbon groups at one end; (2) having one or more portions containing a hydrophilic group in a molecule; and (3) having one or more reactive functional groups which are capable of covalently binding with the substance to be modified at an end different from the end in the above (1).

Abstract: A phospholipid derivative represented by the following formula (I) wherein R1CO and R2CO independently represent an acyl group; R3 represents hydrogen atom, or a hydrocarbon group; symbol “a” represents an integer of 0 to 4; symbol “b” represents 0 or 1, provided that when a is 0, b is 0; X represents hydrogen atom, an alkali metal atom, an ammonium, or an organic ammonium; A1O and A3O represent an oxyalkylene group containing oxyethylene group, wherein the ratio of the oxyethylene group to the oxyalkylene group in A1O and A3O is 0.5 or larger in terms of a weight ratio; A2O represents an oxyalkylene group; symbols “m” and “q” represent an average molar number of added oxyalkylene groups; and symbol “n” represent an average molar number of added oxyalkylene groups; provided that m, n and q satisfy the following conditions: 5?m?600, 1?n?45, 0?q?200, 10?m+n+q?600, 0.04?n/(m+n+q), and q/(m+n+q)?0.

Abstract: A phospholipid derivative represented by the following formula (1): wherein [PG]k represents a residue of polyglycerin having a polymerization degree of k, wherein k is 2 to 50, R1CO and R2CO independently represent an acyl group having 8 to 22 carbon atoms, symbol “a” independently represents an integer of 0 to 5, symbol “b” independently represents 0 or 1, M represents hydrogen atom, an alkali metal atom, an ammonium, or an organic ammonium, and k1, k2, and k3 represent numbers satisfying the following conditions: 1?k1?(k+2)/2, 0?k2, and k1+k2+k3=k+2. The phospholipid derivative is highly safe for living bodies and can be suitably utilized in drug delivery systems such as liposome, and the like.

Abstract: A phospholipid derivative, utilizable for modification of liposomes and the like, which is a copolymer containing, as essential component units, a component unit A represented by the formula (1), a component unit B represented by the formula (2A) and/or the formula (2B), and a component unit C represented by the formula (3) [R1 and R2 represent hydrogen atom or methyl group, provided that R1 and R2 do not simultaneously represent methyl group; R3 represents a divalent hydrocarbon group having 1 to 3 carbon atoms; AO represents an oxyalkylene group having 2 to 4 carbon atoms; m represents an average molar number of the added oxyalkylene groups and is a number in the range represented as 4?m?100; R4 represents hydrogen atom, a hydrocarbon group or acyl group having 1 to 20 carbon atoms; R5CO and R6CO represent an acyl group having 8 to 24 carbon atoms; R7 represents a divalent hydrocarbon group having 2 to 4 carbon atoms; and X and Y represent hydrogen atom, an alkali metal atom, ammonium or an organic ammonium

Abstract: A phospholipid derivative represented by the formula (1) (Z represents a residue of a compound having 3 to 10 hydroxyl groups; AO represents an oxyalkylene group having 2 to 4 carbon atoms; R1CO and R2CO represent an acyl group having 8 to 22 carbon atoms; X represents hydrogen atom, an alkali metal atom, ammonium or an organic ammonium; “a” represents an integer of 0 to 4; “b” represents 0 or 1; Q represents hydrogen atom or methyl group; m represents an average number of moles of the oxyalkylene group added; and m, k1, k2, and k3 are numbers satisfying the following conditions: 3?m?200, 9?m×(k1+k2+k3)?1000, 1?k1?2, 0?k2?9 and 0?k3?9, and 3?k1+k2+k3?10), which is highly safe for living bodies, and is suitably used for solubilization and dispersion of physiologically active substances and the like, or in the fields of drug delivery systems such as liposomes and cosmetics.

Abstract: A polyalkylene oxide-modified phospholipid represented by formula (1) defined in the specification, has a monoacyl phospholipid content of not more than 3% by weight and a content of a base having a nitrogen atom of not more than 0.02% by weight.

Abstract: A cell in which a reaction product of a substance to be modified and an amphipathic compound is non-covalently bound to a cell membrane, wherein said compound has the following features:

Abstract: A polyalkylene oxide-modified phospholipid represented by formula (1) defined in the specification, has a monoacyl phospholipid content of not more than 3% by weight and a content of a base having a nitrogen atom of not more than 0.02% by weight.

Abstract: A composition is provided which comprises catalase modified with a copolymer (A) and a second copolymer, i.e., copolymer (B). The copolymer (A) comprises an alkenyl ether, maleic anhydride, and at least one monomer selected from the group consisting of unsaturated carboxylic acid, vinyl compound and olefin, and copolymer (B) consists of an ethylenically unsaturated monomer and a monomer selected from the group consisting of a monomer having a carboxyl group and a monomer having an acid anhydride group, or a salt of the copolymer (B).

Abstract: A process for producing a polyoxyalkylene derivative substituted with succinimidyl group which comprises reacting a polyoxyalkylene compound having carboxyl group at ends with N-hydroxysuccinimide in an inert solvent in the presence of dicyclohexylcarbodiimide; dissolving an obtained reaction product into chloroform, an amount by weight of chloroform being 0.5 to 10 times as much as an amount by weight of the polyoxyalkylene compound having carboxyl group at ends; and crystallizing the polyoxyalkylene derivative substituted with succinimidyl group by adding an aliphatic hydrocarbon having 5 to 8 carbon atoms to a resultant solution, an amount by weight of the aliphatic hydrocarbon being 2 to 10 times as much as an amount by weight of chloroform. Materials can be handled with safety, and a highly pure polyoxyalkylene derivative substituted with succinimidyl group which does not cause turbidity in an aqueous solution and has an excellent quality as a material for drugs can be produced.

Abstract: A process for producing a polyoxyalkylene derivative substituted with succinimidyl group which comprises reacting a polyoxyalkylene compound having carboxyl group at ends with N-hydroxysuccinimide in an inert solvent in the presence of dicyclohexylcarbodiimide; filtering an obtained reaction product; and crystallizing the polyoxyalkylene derivative substituted with succinimidyl group by adding isopropyl alcohol to a filtrate obtained by the filtration, an amount by weight of isopropyl alcohol being 1 to 100 times as much as an amount by weight of the polyoxyalkylene compound having carboxyl group at ends.Materials can be handled with safety in the process of the present invention, and a highly pure polyoxyalkylene derivative substituted with succinimidyl group which does not cause turbidity in an aqueous solution and has an excellent quality as a material for drugs can be produced.