At 0° C., 217 mg (1.15 mmol) of TiCl4 (1 M in CH2Cl2) were added to a solution of 500 mg (1.15 mmol) of methyl 8-{2-[(4-cyclohexylbenzyl)oxy]phenyl}-6-oxo-octanoate XIV and 190 mg (1.26 mmol) of methyl 4-aminobenzoate in 12.5 ml of 1,2-dichloroethane. The mixture was stirred at room temperature for 20 min, and 383 mg (1.72 mmol) of sodium triacetoxyborhydride were then added. The progress of the reaction was monitored by thin-layer chromatography, and after the reaction had ended, water was added. The mixture was extracted with ethyl acetate and the combined organic phases were dried over Na2SO4. The product was purified chromatographically (silica gel, gradient cyclohexane/ethyl acetate 10:1 to 0:100).
