Twelve new plaunotol analogues were synthesized from comercially available geraniol which were separated in two pathways according to their structures. 2, 6-Dimethyl-2, 6-octadien-1, 8-diol (4) has been synthesized by selenium dioxide hydroxylation as the key step. The synthesis of another new compounds composed of alkylation of malonateesters with geranyl chloride in the presence of base then second alkylation was carried out with halo-esters. The alkylation products were decarboxylated with neutral condition and reduced with lithium aluminium hydride to obtain corresponding alcohols. These compounds have been tested for their biological activity using cAMP phosphodiesterase. Some of these compounds showed modest inhibition of cAMP. Only four new compounds had enough activity to be able to determine their IC50 values.