Farnesyl Protein Transferase Inhibitor ZARNESTRA™ R115777 - History of a Discovery

R115777 (R)-6-amino[(4-chlorophenyl)(1-methyl-1H-imidazol-5-yl)methyl]-4-(3-chlorophenyl)-1-methyl-2(1H)-quinolinone is a potent and selective inhibitor of farnesyl protein transferase with significant antitumor effects in vivo subsequent to oral administration in mice. Taking its roots into Janssen's ketoconazole and retinoic acid catabolism programs, our interest into Ras prenylation process led us stepwise to identify the key structural features of R115777. Methodology, structure activity relationships, and pharmacology will be presented. R115777 is currently in phase III clinical evaluation.