dissolved in dioxane (40 mL) was hydrogenated over palladiumon-barium sulfate catalyst (0.02 g) in the presence of quinoline (0.2 g). When the hydrogen absorption ceased, the catalyst was filtered off and the solvent was removed in vacuo, leaving a residue (0.081 g), which was dehydrated in xylene-tetrahydrofuran (4:1 v/v) solution with boron trifluoride etherate (0.9 mL) in the presence of hydroquinone (0.02 g) by boiling in a reflux condenser during 3.5 h. After cooling, the reaction mixture was treated with 10% aqueous sodium hydroxide (4 mL), taken in ethyl ether (150 mL), washed with water, and dried over anhydrous magnesium sulfate. Upon removal of the solvent the residue was purified by chromatography which gave 4 oil (0.052 g, 56% yield):

No abstract

No abstract

No abstract

No abstract

No abstract

No abstract

No abstract