To a solution of sucrose (3 g) in distilled water (40 mL) was added Baker's yeast (2 g). The suspension was heated at 32° C. for 1 h. The content of the flask was then poured into a flask containing ketoester 60 (4 g, 9.88 mmol, dissolved in 4 mL of methanol). Stirring was continued at 32° C. for 24 h after which additional sucrose (3 g) in warm (40° C.) distilled water was added. After 48 h, the suspension was filtered through a pad of Celite. The pad was washed with water and the aqueous layer was extracted with ethyl acetate (3×250 mL). The combined organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was subjected to flash chromatography (30% EtOAc/Hexane) to afford alcohol 62 (1.7 g, 42%).
