Aggregation of steroidal lariat ethers: the first example of nonionic liposomes (niosomes) formed from neutral crown ether compounds

Abstract
N-(3-Dihydrocholesteryloxycarbonylmethyl)-(1) and N-(3-cholesteryloxycarbonylmethyl)-1-aza-4,7,10,13-tetraoxa-cyclopentadecane (2) aggregate in water to from the first examples of niosomes based on amphiphiles having an uncomplexed crown ether residue as the head group.