76014-93-2Relevant academic research and scientific papers
A synthesis of the phenolic lipid, 3-[(Z)-pentadec-8-enyl] catechol, (15:1)-urushiol
Tyman, John H. P.,Schofield, Brian G.,Khor, Choong H.
, p. 101 - 108 (2007/10/03)
A synthesis of (15:1)-urushiol, urushiol monoene, 3-[(Z)-pentadec-8-enyl] catechol, 1,2-dihydroxy-3-[(Z)-pentadec-8-enyl] benzene, one of the toxic principles of Rhus toxicodendron and of Rhus vernicifera is described. 6-Chlorohexan-1-ol protected at the OH group with ethyl vinyl ether reacted with 2,3-dimethoxybenzaldehyde in the presence of lithium to give, after removal of the protective group with methanolic 4-toluenesulphonic acid, 1-(2,3-dimethoxyphenyl) heptane-1,7-diol. Catalytic hydrogenolysis in ethanol with palladium-carbon selectively afforded 7-(2,3-dimethoxyphenyl)heptane-1-ol accompanied by a small proportion of the 7-(3-methoxyphenyl)heptane-1-diol, formed by demethoxylation. Reaction of the dimethoxy compound with boron tribromide resulted in both bromination and demethylation to give 7-(2,3-dihydroxyphenyl) heptylbromide. This bromide in tetrahydrofuran (THF) containing hexamethylphosphoric triamide reacted with excess lithium oct-1-yne to give 3-(pentadec-8-enyl)catechol which, by catalytic hydrogenation in ethyl acetate containing quinoline, selectively formed the required cis product, 3-[(Z)-pentadec-8-enyl]catechol which was identical chromatographically and spectroscopically with urushiol monoene separated from the natural product.
Vesicant Principles of Poison Ivy and Related Plants: Synthesis of the Urushiols, 1,2-Dihydroxy-3-benzene and 1,2-Dihydroxy-3-pentadecylbenzene
Halim, Haroen,Locksley, Harry D.,Memon, Janmohammed J.
, p. 2331 - 2337 (2007/10/02)
New syntheses of 1,2-dihydroxy-3-benzene (1) and 1,2-dihydroxy-3-pentadecylbenzene (4), vesicant principles of Poison Ivy (Rhus radicans) and other species of Anacardiaceae, are described starting from 1,2-dimethoxybenzene (7).The lithiation of 1,2-dimethoxybenzene (7) has been re-examined and the yield of the product, 2,3-dimethoxyphenyl-lithium (8), re-determined.The reaction of the aryl-lithium with 1,7-dibromoheptane has been studied by g.l.c., using tributyltin chloride as a quenching reagent.The extracts of two plants of the Anacardiaceae family, Semecarpus vitiensis Engl. and Melanorrhoea beccari Engl., have been examined for the presence of urushiols.The bark of the latter has been found to contain gallic acid.
