The condensation of 6-bromohexanoic acid (I) with triphenylphosphine in refluxing acetonitrile gives the corresponding phosphonium salt (III), which is submitted to a Wittig condensation with phenyl 3-pyridyl ketone (IV) by means of NaH in DMSO, yielding a mixture of the title product and its (Z)-isomer (V). This mixture of isomers is separated by fractional crystallization or HPLC and the isomeric compound (V) is treated with refluxing aqueous 25% HBr to perform its isomerization to CV-415.