Catalytic hydrogenation of optically active alcohol esters of 2, 2, 5, 5-tetramethyltetia-hydrofurylidene-3-acetic acid (VI) or of 2, 2, 5, 5-tetramethyldihydrofuryl-3-acetic acid (X), using l-menthol, 1, 2:5, 6-diisopropylidene-α-D-glucofuranose, and 1, 2:5, 6-dicyclohexylidene-α-D-glucofuranose, afforded, after hydrolysis, optically active 2, 2, 5, 5-tetramethyltetrahydro-furyl-3-acetic acid. The maximum optical yield (62.5%) was obtained when the dicyclohexylidene glucose derivative ester of VI was hydrogenated in dioxane though in low reduction yield. The stereochemical course was explained by the Prelog generalization, but a unique effect due to the ring structure was considered. The optically pure acid was converted into pyrocin without racemization.