The opticallyactive isomers of cyclamen aldehyde 1a were synthesized from a chiral intermediate prepared by lipase-catalyzed enantioselective transesterification of a prochiral diol with vinyl acetate. The absolute configuration of the enantiomer of 1a with dextrorotatory in chloroform was determined to be (S)-configuration. The results of an olfactory evaluation of the prepared isomers are also reported