1. A method of synthesis of compound of the dispirane type has been proposed. 4, 8-Di-(β-ethylcarboxyethyl)-dispiro (5, 1, 5, 3)-hexadecantrione-3, 7, 11 was obtained from the ethyl ester of 2, 2, 6, 6-tetra(β-carboxyethyl)-cyclohexanone by the Dieckmann's ring closure. The former was hydrolyzed and decatboxylated giving dispiro (5, 1, 5, 3) hexadecantrione-3, 7, 11. Dispirane of this type formed from three six-carbon rings so far has not been reported 2. Dispiro (5, 1, 5, 3) hexandecantrione-3, 7, 11 was allowed to react with acrylonitrile forming 2, 2, 4, 4, 10, 10, 12, 12-octo(β-cyanoethyl)-dispiro (5, 1, 5, 3) hexadecantrione-3, 7, 11. Synthesis of polyspiranes from the latter compound is now in progress in this laboratory.