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 polyalkylene glycol derivative containing a compound of the formula (1): wherein R is a hydrocarbon group having 1 to 24 carbon atoms, OA1 and OA2 are each an oxyalkylene group having 2 to 4 carbon atoms, the groups represented by R are the same or different from each other in one molecule, the groups represented by OA2 are the same or different from each other in one molecule, m is an average number of moles of the above oxyalkylene group added, m represents 10 to 1000, X represents a functional group capable of chemically reacting with a bio-related substance, and Y is a linker and represents an ether bond, an amide bond, a urethane bond, an ester bond, a secondary amino group, a carbonate bond, or an alkylene group containing these bonds, polydispersity Mw/Mn of the above polyalkylene glycol derivative in gel permeation chromatography satisfying the following relationship: Mw/Mn?1.08 wherein Mw represents a weight average molecular weight and Mn represents a number average molecular weight.

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 polyalkylene glycol derivative containing a compound of the formula (1): wherein R is a hydrocarbon group having 1 to 24 carbon atoms, OA2 is an oxyalkylene group having 2 to 4 carbon atoms, the groups represented by R are the same or different from each other in one molecule, the groups represented by OA2 are the same or different from each other in one molecule, m is an average number of moles of the oxyalkylene group added, m represents 10 to 1000, and X represents a functional group capable of chemically reactive with a bio-related substance, polydispersity Mw/Mu of the above polyalkylene glycol derivative in gel permeation chromatography satisfying the following relationship: Mw/Mn?1.07 wherein Mw represents a weight average molecular weight and Mn represents a number average molecular weight.

Abstract: A modified bio-related substance, wherein at least one poly(alkylene glycol)oxy group represented by the following formula (1) is combined in a molecule: wherein R is a hydrocarbon group having 1 to 24 carbon atoms, OA1 and OA2 are each an oxyalkylene group having 2 to 4 carbon atoms, the groups represented by R are the same or different from each other in one molecule, and the groups represented by OA2 are the same or different from each other in one molecule, n and m are each average number of moles of the oxyalkylene group added, n represents 0 to 1000, and m represents 10 to 1000.

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 polyoxyalkylene derivative is represented by formula (I): wherein Z represents a residue of a compound having 2 to 8 hydroxyl groups; AO represents an oxyalkylene group having 2 to 18 carbon atoms; n and m each represent an integer of 0 to 2000 provided that both n and m do not represent 0; a and b each represent an integer satisfying the relationships: 2?a+b?8 and 1?b; R represents a hydrocarbon group having 1 to 30 carbon atoms; and X represents a divalent hydrocarbon group having 3 to 10 carbon atoms.

Abstract: A modified bio-related substance, wherein at least one poly(alkylene glycol)oxy group represented by the following formula (1) is combined in a molecule: wherein R is a hydrocarbon group having 1 to 24 carbon atoms, OA1 and OA2 are each an oxyalkylene group having 2 to 4 carbon atoms, R and OA2 are the same or different from each other in one molecule, n and m are each average number of moles of the oxyalkylene group added, n represents 0 to 1000, and m represents 10 to 1000.

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 polyoxyalkylene derivative is represented by formula (I): 1

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: An oxirane derivative and process for preparation of the same, having a high purity characterized in terms of gel permeation chromatography and thin layer chromatography. The oxirane derivative is useful as a starting material for medical purposes, and mainly drug delivery systems.

Abstract: The present invention provides an high purity and high molecular oxirane derivative useful as a starting material for medical purposes, mainly drug delivery system, and a process for the preparation thereof.