合成路线1

Condensation of isobutyrophenone (IV) with the lithium derivative of (S)-methyl p-tolyl sulfoxide (IX) produced alcohol (X) as a diastereomeric mixture. After chromatographic separation of the desired diastereoisomer, the methylsulfanyl group was selectively oxidized to sulfone (XI) with m-chloroperbenzoic acid. Reduction of the tolyl sulfoxide moiety of (XI) by means of NaI in the presence of acetyl chloride led to the corresponding sulfide (XII). Cyclization of the hydroxy sulfide (XII) to epoxide (XIII) was accomplished via S-alkylation with triethyloxonium tetrafluoroborate. Finally, opening of the chiral epoxide (XIII) with triazole (XIV) in the presence of K2CO3 furnished the title compound.