抄録
De-epoxidation of epoxide carotenoids to their parent hydrocarbons without changing their basic structures may contribute to give useful information for detecting or identifying known or unknown epoxide carotenoids. Three methods were evaluated on some β-carotene epoxides for this purpose.
1. Xanthate method: Epoxides were refluxed with ROCSSK in ROH (R=Et or n-Bu). This method was found to be effective for de-epoxidation of two oxiranering compound, but not for one oxirane- or furan-ring type compound.
2. Sulfuric acid method: Epoxides were shaken with 50% H2SO4 in n-hexane at room temperature. This method would be available simply for the de-epoxidation of a one oxirane-ring compound, but not for a furanoid oxide type compound. Two oxirane-ring compounds gave several stepwise de-epoxidized products on this treatment.
3. Reduction method: Epoxides were treated with LiAlH4 in absolute ether. Hydroxyhydro derivatives which could be investigated further were formed together with a small amount of de-epoxidized products. Several applications were suggested.
