Stable analogues of farnesyldiphosphate, possessing an aniline-type portion in the prenyl-mimic moiety and phosphonoacetamido(oxy) groups in the place of the metabolically unstable diphosphate unit, were synthesised and submitted to biological assays. The enzyme inhibition tests performed on FTase and GGTase I show that the newly synthesised compounds based on a combination of the aniline-containing