Penicillinacylase from , immoblized on Eupergit C beads catalyzes the hydrolysis in water/CH3CN 10:1, at pH 7.5 and 23° C, of a set of O-phenylacetate esters of primary carbinols. The highest enantioselectivity is observed in the case of the 2,2-dimethyl-1,3-dioxolane-4-methanols structurally related to the penicillin (1) framework. Minor modifications of this basic structure are not altering the acceptability