Structure of mefloquine and synthesis of 4-position library. The structure of mefloquine is indicated (1). The intermediate scaffold 4-(oxiran-2-yl)-2,8-bis(trifluoromethyl)quinoline (3) was synthesized from bis(trifluoromethyl)quinolin-4-ol (2) by the addition of POBr3, at 75°C - 150°C for 2 h with 91% yield. The resulting 4-bromo-2,8-bis(trifluoromethyl) quinoline was dissolved in tetrahydrofuran, cooled to -78°C and subjected to n-butyllithium. N,N-dimethylformamide was subsequently added to afford 2,8-bis(trifluoromethyl)quinoline-4-carbaldehyde. Utilization of Corey's dimethylsulfonium methylide provided racemic epoxide (3). The epoxide (3) can also be purchased commercially from Bioblocks (San Diego, California). The quinoline scaffold (3) was diversified at the 4-position in a single step with commercially available nucleophiles.