合成路线1

The synthesis of MDL-100907 [11C]-labeled at the 3'-methoxy group has been described: Condensation of 2-(4-fluorophenyl)ethyl bromide (I) with piperidine-4-carboxylic acid ethyl ester (II) by means of K2CO3 in DMF gives 1-[2-(4-fluorophenyl)ethyl]piperidine-4-carboxylic acid ethyl ester (III), which is treated with N,O-dimethylhydroxylamine and ethylmagnesium bromide in THF yielding the carbohydroxamic ester (IV). The condensation of (IV) with the silylated guaiacole (V) by means of n-BuLi in THF affords the 4-benzoylpiperidine (VI), which is reduced with NaBH4 in methanol giving the racemic carbinol (VII). Optical resolution of (VII) by esterification with (S)-2-methoxy-2-phenylacetic acid (VIII) by means of DCC and DMAP in chloroform followed by column chromatography yields the diastereomer (IX), which is simultaneously hydrolyzed and desilylated with K2CO3 in methanol affording the chiral carbinol (X). Finally, (X) is methylated with [11C]-methyl iodide and K2CO3 in methanol.