α-hydroxy Farnesyl phosphonic acid is a nonhydrolyzable analog of farnesyl pyrophosphate which acts as a competitive inhibitor of farnesyl transferase (FTase). At concentrations greater than 1 μM, α-hydroxy farnesyl phosphonic acid inhibits the processing of Ras in Ha-ras-transformed NIH3T3 cells.
S-Farnesyl thioacetic acid is an analog of S-farnesyl cysteine which behaves as a competitive inhibitor of isoprenylated protein methyltransferase (also known as S-adenosylmethionine-dependent methyltransferase). It can also inhibit methylation of both farnesylated and geranylgeranylated substrates.