Polyhydroxy Fatty Acids Derived from Sophorolipids

Starting from 17-hydroxyoleic acid, which is readily available from acid alcoholysis of sophorolipids, several new polyhydroxy fatty acids have been synthesized. These compounds contain from 2 to 4 hydroxy groups, in some instances combined with other functional groups. The added hydroxy groups can be incorporated in the C18 chain in a variety of geometries, for example spaced widely throughout the chain at C1, C8, and C17. This regiochemical control will be of use in structure/function studies involving materials constructed from these hydroxy fatty acids. A further benefit is that the hydroxy groups can be present in protected or free states. The principal reactions used to introduce extra hydroxy groups are selenium oxide-mediated allylic hydroxylation, osmium-catalyzed dihydroxylation, and borohydride reduction of a carboxylic ester. These new compounds are expected to be of use in a number of areas, but particularly as building blocks for polymers or components of lubricant formulations.