Potassium Hydroxide → 6-[3-(1-Adamantyl)-4-(3-hydroxypropyloxy)phenyl]-2-naphthoic acid

0.57 g (1.21 mmol) of the ester obtained in Example 7 in suspension in 30 ml of n-butanol is treated with 400 mg of potassium hydroxide. The reaction mixture is heated for 3 h at 100° C., then evaporated to dryness, and is taken up in 50 ml of water and washed with ether. The aqueous phase is acidified to pH=1 with concentrated HCl and extracted with 600 ml of ether. The organic phase is washed with water, dried over magnesium sulphate, filtered and evaporated to give 0.49 g (90%) of the expected acid which melts at 277°-279° C.