HPLC and LC-MS studies of the transesterification reaction of methylparaben with twelve 3- to 6-carbon sugar alcohols and propylene glycol and the isomerization of the reaction products by acyl migration.

Sugar alcohols and parabens are commonly used ingredients in oral suspension formulations. However, their possible incompatibility because of transesterification reaction is a concern during formulation development. In order to gain more knowledge about the reaction, a high-performance liquid chromatographic (HPLC) method is developed to separate the transesterification reaction products of methylparaben preservative with twelve 3- to 6-carbon sugar alcohols and propylene glycol.