How is 1-Hydroxy-3,6,9,12,15,18-hexaoxahenicosan-21-oic acid (CAS: 1347750-85-9) typically synthesized?

1-Hydroxy-3,6,9,12,15,18-hexaoxahenicosan-21-oic acid can be synthesized through a series of alkylation and hydroxylation reactions. The key steps involve the introduction of multiple hydroxyl groups and the formation of the carboxylic acid group. Common catalysts include Transition metals like palladium or platinum, and the reaction is typically carried out under anhydrous conditions to ensure high selectivity and yield.