A study of the chemistry of picrotoxinic acid

Abstract

Picrotoxin is an intensely bitter and physiologically active substance, first isolated in 1812 by the French apothecary, P. Boullay from the berries of an East Indian creeper (anamirta cocculus). It was first thought to be an alkaloid but nitrogen was found to be absent on analysis and picrotoxin is now classified as an amaroid. The amaroids include such bitter principles extracted from plants as Santonin, Artenisin, Alantolactone, Isoalantolactone and Tutin. The Italian workers, Paterno and Oglialoro2.3.4 were the first to investigate the substance rationally, and were actually the first to involve the bromination method of separating picrotoxin into two components, picrotoxinin and picrotin. Barth and Kretschy5. also obtained these components by fractional crystallisation of picrotoxin from benzene in 1880, and then followed a controversy as to whether picrotoxin was a mixture or a compound.6.7.8.9.10 It was finally shown to be an equimolecular compound of pixrotoxinin and picrotin.11.12. Meyer and Bruger established the first reproducible separation of picrotoxin into its constituents in 1898, when they showed that the presence of a double bond in picrotoxinin allowed its separation from picrotin as the monobromo-derivative. Analysis by combustion and molecular weight determinations gave C15H16O614. as the molecular formula for picrotoxinin, and C15H18O7 as that for picrotin.