Long-chain phenols

Abstract Fused-silica capillary gas-liquid chromatography has been used for the separation of both the trimethylsilyl and methylene ether derivatives of some long-chain substituted benzene-1,2-diol (catechol) lipids from Melanorrhoea usitata . The sap contains congeners of urushiol (8%), laccol (57%), thitsiol (26%), 3-(phenylalkyl) catechols (8%) and 4-(phenylalkyl)catechols (1%), and many of these metabolites were identified by gas chromatography-mass spectrometry. Reversed-phase liquid chromatography was used to isolate the main chemical component present in both the laccol and thitsiol. These were characterised as (8′Z,11′Z)-3-(heptadeca-8′,11′-dienylcatechol and (8′Z,11′Z)-4-(heptadeca-8′,11′-dienyl)catechol, respectively, by a sequential oxidation scheme whereby methyl esters of the degradation products were obtained and subsequently analysed by gas chromatography-mass spectrometry.