合成路线1

The reaction of 4-hydroxybenzyl alcohol (V) with ethyl 2-bromoacetate (XI) by means of K2CO3 gives the phenoxyacetate (XII), which is then treated with SOCl2 in THF to obtain the benzyl chloride (XIII). Reaction of (XIII) with the indole derivative (VII) by means of NaH in DMF yields the adduct (XIV), whose ester group is reduced with LiAlH4 in THF to afford the 2-hydroxyethoxy compound (XV). Treatment of (XV) with CBr4 and PPh3 in THF provides the 2-bromoethoxy compound (XVI), which is converted into compound (XVIIII) by reaction with hexamethyleneimine (homopiperidine) (XVII) in THF. Finally, compound (XVIII) is debenzylated by hydrogenation with either H2 over Pd/C in ethanol/THF or with cyclohexadiene and Pd/C in THF/EtOH.

合成路线2

The intermediate 2-[4-(chloromethyl)phenoxy]acetic acid ethyl ester (IV) has been obtained as follows: The reaction of 4-hydroxybenzyl alcohol (I) with ethyl 2-bromoacetate (II) by means of K2CO3 gives the phenoxyacetate (III), which is then treated with SOCl2 in THF to obtain the desired intermediate (IV). The cyclization of 4-(benzyloxy)aniline (V) with 2-bromo-1-[4-(benzyloxy)phenyl]-1-propanone (VI) by means of TEA in DMF gives 5-(benzyloxy)-2-[4-(benzyloxy)phenyl]-3-methyl-1H-indole (VII), which is alkylated with the intermediate (IV) by means of NaH in DMF to yield the adduct (VIII). The reduction of the ester group of (VIII) with LiAlH4 in THF affords the 2-hydroxyethoxy compound (IX), which is treated with CBr4 and PPh3 in THF to provide the 2-bromoethoxy compound (X). The reaction of (X) with piperidine in THF gives the piperidinoethoxy compound (XI), which is finally debenzylated by hydrogenation with H2 over Pd/C in ethanol/THF to afford the target indole derivative.

合成路线3