An asymmetric synthesis of the selective C 1 7 , 2 0 -lyase inhibitor 2 has been established in eight steps from 2,3-dihydroxynaphthalene 9. The key steps are the enantioselective oxidation of ketone 17 to the chiral α-hydroxy ketone 18 and the diastereoselective Grignard reaction of 18 to the (2R,3S)-diol 21. In addition, a simple procedure for the preparation of imidazolyl 1,4-dimagnesium bromide has been established; the Grignard reaction of 11 using this reagent in the presence of cinchonine provided 2 with 44% ee.