The bis-spiroepoxide dithiane dioxide has been attempted to be synthesised as its role as an intermediate in the synthesis of diaminopimelic acid (DAP). The first method was carried out by reacting the 3-dithiane-2- diethylphosphonate 4 with an aqueous solution of the commercially available glutaraldehide resulting the bis-ketene dithiane dioxide 5. The second alternative method was involving t…