The farnesyltransferase inhibitor pepticinnamin E was synthesized and shown to have the S configuration at the central, non-proteinogenic amino acid. Using a recombinant yeast farnesyltransferase the biological activity of the natural product and structural analogues was determined. It was shown that pepticinnamin E is a bisubstrate inhibitor. Furthermore, several structural parameters were identified that decisively influence inhibition of the farnesyl transfer
