The alkylation of 2-phenyl-4-pentenenitrile (I) with 2-(trimethylsilyl)ethoxymethyl chloride (II) in the presence of LDA afforded (III), which was reduced to aldehyde (IV) by means of DIBAL. Reductive amination of (III) with methylamine and NaBH(OAc)3 produced amine (V) and subsequent condensation with benzenesulfonyl chloride (VI) yielded sulfonamide (VII). A two-step oxidation of (VII) with osmium tetroxide and N-methylmorpholine-N-oxide, followed by sodium periodate cleavage of the resulting diol (VIII) generated aldehyde (IX). Further reductive amination of (IX) with piperidine derivative (X) gave adduct (XI). The (trimethylsilyl)ethoxy protecting group of (XI) was finally cleaved by means of trifluoroacetic acid to furnish the title compound.