The optically active tetracyclic ABCD ring system 2 of (−)-kampanol A (1), a novel Ras farnesyltransferase inhibitor from a microorganism, was efficiently synthesized starting from the known ketol 4 as a model study. The synthetic method involves conjugate addition reaction of the Grignard reagent of the bromobenzene derivative 14 to the α-methylene ketone 10 to form the coupling product 15 and ph
An enantioselective synthesis of the tetracyclic ABCD ring system (4) of kampanols, novel Ras farnesyltransferase inhibitors from a microorganism, was efficiently achieved for the first time starting from the known trans-decalone derivative 9. The synthetic method involves the following two key steps: (i) a conjugate addition reaction between the α-methylene ketone 6 and the Grignard reagent (7) of