Abstract: Enone 1, prepared from cyclopentadiene, was obtained in optically pure form by resolution with (+)-N, S-di-methyl-S-phenylsulfoximine or by a procedure involving asymmetric semihydrolysis of meso-3 catalyzed by electric eel acetylcholinesterase. The absolute configuration of (+)-1 was assigned as S, S on the basis of a comparative optical rotary dispersion study. The lower prostanoid side chain was added to (+)-1 as an ...