Sughrue, Mion, Zinn, Macpeak & Seas
Lipid membrane structures
 Lipid membrane structures containing, in the lipid membrane thereof, a compound represented by formula (I): ##STR1## wherein R.sub.1 represents a hydrogen atom or a fatty acid residue; R.sub.2 represents a hydrogen atom or an acyclic hydrocarbon residue; R.sub.3 represents an amino group, a guanidino group or an amidino group; and n represents an integer of from 1 to 6; provided that R.sub.1 and R.sub.2 do not represent hydrogen atoms at the same time, or a salt thereof. The lipid membrane structures exhibit excellent specific affinity for tumor cells and can be delivered preferentially to tumor cells. 
Daiichi Pharmaceutical Co., Ltd.
A Y A Y
A61K Y10S A61K Y10T
inventional additional inventional additional
Yasuyoshi Munehiro Sadao Hiroshi Hitoshi
Kawato Tomikawa Hirota Kikuchi Yamauchi