Natural (+)-dactyloxene-B (12) and -C (13) have been synthesized starting from (+)- trans-2, 5, 6-trimethyl-l-cyclohexene-l-carbaldehyde (1) which is shown to have the (5 S, 6 R)-configuration by chemical correlation with (+)-(2 R, 3 S, 6 S)-2, 3, 6-trimethylcyclohexanone. The absolute configurations are therefore (2 R, 5 R, 9 S, 10 R) for (+)-dactyloxene-B and (2 R, 5 S, 9 S, 10 R) for (+)-dactyloxene-C.