PROBLEM TO BE SOLVED: To provide a novel asymmetrical bicephalic lipid molecule capable of being synthesized easily from a raw material easily available and capable of producing an asymmetric nanotube selectively with high yield at mild conditions, and an asymmetric nanotube formed of the lipid molecule and having high long-term storage stability, and also to provide an encapsulated medicine composition using a cationic medicine-asymmetric nanotube complex as an active ingredient and having a high stimulation-response sustained-release function, the cationic medicine-asymmetric nanotube complex being formed by selectively encapsulating cationic medicines, such as doxorubicin, in the asymmetric nanotube at a high concentration.SOLUTION: There is provided: the asymmetrical bicephalic lipid molecule capable of forming the novel asymmetric nanotube represented by general formula (1) or a salt of the asymmetrical bicephalic lipid molecule. (In the formula, n represents an integer of 8-16, m represents an integer of 1-4, and a hydroxy group at the 1-position of 2-glucosamine, which is shown by a wavy line in the formula, represents one of an α anomer and a β anomer, or an equilibrium mixture of the anomers).COPYRIGHT: (C)2012,JPO&INPIT【課題】入手しやすい原料から簡便に合成でき、かつマイルドな条件で非対称ナノチューブを選択的かつ高収率に製造できる新規な非対称双頭型脂質分子及び当該脂質分子により形成される長期保存安定性の高い非対称ナノチューブの提供。また、当該非対称ナノチューブにドキソルビシンなどのカチオン性薬剤を選択的、高濃度にカプセル化したカチオン性薬剤-非対称ナノチューブ複合体を有効成分として用いた、刺激応答性徐放機能の高いカプセル化薬剤組成物の提供。【解決手段】下記一般式(1)で表される新規な非対称ナノチューブ形成能を有する非対称双頭型脂質分子又はその塩。(式中、nは8~16の整数であり、mは1~4の整数を表す。また、式中の波線で表記した2-グルコサミンの1位水酸基はα、βアノマーのいずれか、あるいはその平衡混合物を表す。)。【選択図】なし
