Spiroepoxycyclohexadienone dimers C obtained by Adler oxidation of salicyl alcohols display cytotoxicity against L1210, HT29 and AS49. The alkylating properties of 1 are shown by ready addition of benzylamine to generate a new azabicyclo[2,2,2]octane ring system, and of N-methylbenzylamine to give mono- (together with partial aromatization) and bisalkylated products.