Chemically Talking, this molecule is "halfway" among Sorbitan Oleate and Sorbitan Trioleate, indicating that it's also an attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the unsaturated fatty acid Oleic Acid, but in a ratio of two:3 hence the "Sesqui" aspect inside the molecule's identify. In addition, it helps to deliver h2o-