Resolution of racemic 4-hydroxy-2-cyclopentenone with immobilized penicillin G acylase

Enantiomerically pure 4-oxo-2-cyclopentenyl derivatives were prepared by kinetic resolution with penicillin G acylase (EC 3.5.1.11) immobilized on an epoxy activated polymer. The enzyme selectively hydrolyzes the phenylacetyl ester of the (S)-enantiomer to give the (S)-alcohol. The enantioselectivity E increases from 12.4 in 0.05 M phosphate buffer, to E = 100–110 in acetonitrile-buffer (20% v/v) and E >200 in diisopropyl ether. The immobilized enzyme is stable and retains >90% of its activity after 10 recycles over one week at room temperature.

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(R)-4-Oxocyclopent-2-en-1-yl 2-phenylacetateC13H12O3[α]D25=-40.5 (c 0.5, MeOH)Source of chirality: enzymatic resolutionAbsolute configuration: (R)

(S)-4-((tert-Butyldimethylsilyl)oxy)cyclopent-2-enoneC11H20O2Si[α]D25=-65.2 (c 1.3, MeOH)Source of chirality: enzymatic resolutionAbsolute configuration: (S)