The title compound is prepared according to the following procedure. To solution of 2-(8-bromo-1-ethyl-6-isopropyl-1,3,4,9-tetrahydro-pyrano[3,4-b]indol-1-yl)-ethanol (1.0 mmol) in dried acetonitril (10 mL) at under nitrogen is added triethylamine (1.5 mL), tri-o-tolylphosphine (0.4 mmol), styrene (2.0 mmol), and tri(dibenzylideneacetone)dipalladiumn (0) (0.1 mmol). The reaction mixture is heated at 90° C. (oil bath) overnight. It is quenched with water and extracted with ethyl acetate. Extracts are dried over magnesium sulfate and concentrated under reduced pressure. The chromatography (silica gel) gives the title compound.
