Cholesteryl isobutylcarbonate

Abstract

Cholesteryl isobutylcarbonate, C32H54O3, contains two molecules ( A and B) in the asymmetric unit. The isobutylcarbonate chain of molecule A and the isoprenoid tail of molecule B are each conformationally disordered over two positions. The two distinct molecules form separate stacks along the screw axes so that they are arranged in an antiparallel array, forming monolayers with a thickness of d(001) = 19.412 angstrom. The central regions of the monolayers are characterized by efficient molecular packing and are separated by interface regions, which are more loosely packed.