Preparation and characterization of new micelle-forming cholesterol amphiphiles

New sulfated and sulfonated cholesterol amphiphiles were synthesized and ch aracterized by dynamic light scattering and electron microscopy. The surfac tants form micelles with diameters up to 30 nm. Their critical micelle conc entration values were determined by conductometry and photometric measureme nts. Use of the new amphiphiles enables the transfer of an asymmetric hydro genation reaction into aqueous solution by keeping the activity and increas ing the enantioselectivity. Interesting liquid-crystalline behaviour was ob served.