The inadequacy of the Raney nickel desulfuration method for the structural elucidation of an epoxide-glutathione S-conjugate: desulfuration of phenyloxiran-glutathione S-conjugates to phenyloxiran.
Both of purely separated regioisomers of phenyloxiran-glutathione S-conjugates, conjugate 1 (S-(1-phenyl-2-hydroxyethyl)glutathione) and conjugate 2 (S-(2-phenyl-2-hydroxyethyl)glutathione), afforded phenyloxiran as a common intermediate to the major desulfuration products, phenethyl alcohol and ethylbenzene, and to the minor ones, methylphenylcarbinol and toluene, on the mild treatment with Raney nickel in boiling ethanol. Phenyloxiran formed was hydrogenated to stable phenethyl alcohol and unstable methylphenylcarbinol under the catalytic conditions used, the latter of which was readily deoxygenated to ethylbenzene. The present study indicated that the Raney nickel method, despite of its being recognized to be well established, could not be applicable to the structural assignment of epoxide-glutathione or epoxide-mercapturic acid conjugates.
D055598:Chemical Phenomena; D002621:Chemistry; D004852:Epoxy Compounds; D004988:Ethers, Cyclic; D008401:Gas Chromatography-Mass Spectrometry; D005978:Glutathione; D007202:Indicators and Reagents; D009532:Nickel; D013455:Sulfur; D013997:Time Factors
D004852:Epoxy Compounds; D004988:Ethers, Cyclic; D007202:Indicators and Reagents; D013455:Sulfur; D009532:Nickel; C013690:styrene oxide; D005978:Glutathione