Oxidation of haplophytine (1) with alkaline potassium permanganate has been shown to give the seco product16. This assignment is based on spectroscopic data and comparison of these with spectroscopic data for the analogous seco product8formed on similar oxidation of aspidophytine (3), an acid cleavage product of haplophytine. The course of these oxidations contrasts with that of the oxidation of haplophytine and aspidophytine with alkaline hydrogen peroxide, which gives4and6, respectively, without carbon–carbon bond cleavage.