In 16 ml of cocentrated hydrochloric acid was dissolved 3.8 g (8.5 mmol) of the benzyl compound (122a), and the mixture was heated at 100° C. for 2 hours. After cooling, the mixture was neutralized with sodium hydrogen carbonate, extracted with ethyl acetate, the extract was washed with water, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (1% methanol:ethyl acetate), washed with n-hexane, and filtered to give 2.57 g of 2-[5-(3,5-dichlorophenylthio)-1-ethyl-4-isopropyl-1H-imidazol-2-yl]ethanol (123a) as crystals (yield 85%). mp 80-81° C.
