A solution of 798 mg (1.48 mmol) of ethyl 7E-8-[2-(4-tert-butylbenzyloxy)phenyl]-6-[2-(4-cyanophenyl)ethyl]oct-7-enoate in 20 ml of THF and 20 ml of water is mixed with 71 mg (2.97 mmol) of lithium hydroxide and stirred at 50° C. for 12 hours. Cooling is followed by dilution with water and diethyl ether and separation of the phases. The aqueous phase is acidified with 1 M hydrochloric acid and extracted with diethyl ether. The organic phase is washed with saturated sodium chloride solution, dried over sodium sulfate and concentrated. 700 mg (1.4 mmol, 93% of theory) of the title compound are obtained.
