A variety of substituted cyclopropenone ketals have been prepared by electrophilic trapping (protonolysis and alkylation) of sodium salts of cyclopropenone ketals that have been generated directly from the ketals of 1,3-dichloroacetone derivatives through cyclization with NaNH2 in a liq. NH3/ether mixture.
3-carboxycyclopropene or cyclopropenone derivatives, react with 1-propanethiol to give alkylthiocyclopropanes. None of the cyclopropenes and cyclopropene derivatives investigated reacted with other aminoacid chemical probes. These overall results support that inhibition of desaturases by cyclopropene fatty acids is caused by reaction of the unsaturated moiety with a cysteine residue of the enzyme active site.