Synthesis and pharmacological screening of certain spiro compounds

The synthesis of certain azaspirodione, azaspirane and bis-azaspirodione derivatives is described. Fusing equimolecular amounts of 3-oxaspiro[5.5]undecane-2.4-dione with certain amino compounds afforded the corresponding N-substituted azaspirodiones. Reduction of the N-harolaryl azaspirodiones gave the oxygen-free analogues. Reacting 3-azaspiro[5.5]undecane-2.4-dione with certain secondary amines under the Mannich conditions yielded the expected bases. Reacting one equivalent of ethylene-diamine with two equivalents of 2-oxaspiro[4.4]nonane-1.3-dione and the next higher homologues, viz, the decane and undecane afforded the respective ethylene bis-azaspirodiones. Likewise, on applying the Mannich conditions to the nitrogen analogues of the before-mentioned oxaspirodiones using piperazine as the secondary amine, bis-azaspirodions were obtained. The result of the pharmacological screening of some of the synthesized spiro compounds is included.