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8. In human cells, farnesyl transferase catalyzes the farnesylation of the Ras protein. The inhibition of farnesyl transferase has been demonstrated to be a useful anticancer strategy. HO Farnesyl diphosphate Ras -SH Ras Farnesyl transferase H₂N OH OMe meses H₂N HS HS Compound 1 Compound 2 (a) Explain why the inhibition of farnesyl transfer can lead to anticancer activity. (3 marks) (b) Compound 1 above is a reported farnesyl transferase inhibitor. Explain how this molecule can inhibit the activity of farnesyl transferase. (4 marks) (c) Structural optimizations of Compound 1 have led to the identification of novel farnesyl transferase inhibitor Compound 2 shown above. Briefly explain the rationale for the optimization of the structure of Compound 2 from Compound 1. (4 marks) (d) Briefly point out the disadvantages of Compound 1 and 2 as an anti-cancer drug. (3 marks) Page 6 of 8 Compound 3 (e) Explain why Compound 3 above is expected to inhibit the activity of farnesyl transferase better than Compound 1 and 2. List two strategies used in Compound 3 to improve the drug-like property. (6 marks)