The feasibility of a synthesis of tricyclopolyprenols based on the addition of the isocopalen-15-yl radical either to a 2-methylene-3-hydroxy alkenenitrile or to a methyl 2-methylene-3-hydroxy alkenoate - both prepared by a Baylis-Hillman reaction - is examined. When two model adducts, a β-acetoxy nitrile and a β-mesyloxy ester, were subjected to an elimination reaction, the former gave a trans α,β-unsaturated nitrile whereas the latter gave a cis α,β-unsaturated ester. The reduction of the ancillary cyano or methoxycarbonyl groups into a methyl is also described.

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Four tricyclopolyprenols have been synthesised by addition of the isocopalenyl radical either to a 2-methylene-3-hydroxy alkenenitrile (in the case of (E,E)-tricyclohexaprenol) or to a methyl 2-methylene-3-hydroxy alkenoate (in the case of the three (Z)-tricyclopolyprenols). Elaboration of the newly introduced side chains includes a stereoselective elimination reaction and the reduction of the electron withdrawing groups (-CN or -CO2Me) into a methyl.

:This synthesis of the sesterterpene ent-cheilanthenediol is based on the addition of the isocopal-12-en-15-yl radical to monoprotected methyl 3,4-dihydroxy-2-methylenebutanoate which has been prepared from protected hydroxyacetaldehyde by a Baylis-Hillman reaction. The equatorial tertiary hydroxyl group at C-13 has been obtained by opening an epoxide with lithium diisobutyl-n-butylaluminium hydride.

(EE)-Tricyclohexaprenol has been synthesized by addition of the isocopal- 12-en- 15-yl radical to a 3-hydroxy-2-methylene alkenenitrile, stereoselective elimination of acetic acid from the acetylated adducts, and reduction of the cyano group into a methyl via the corresponding amine.

Addition of the isocopal-12-en-15-yl radical to a methyl 3-hydroxy-2-methylene alkenoate and stereoselective elimination of methanesulphonic acid from the mesylated adducts are the key steps of this synthesis of (Z,Z)-tricyclohexaprenol.