The esterification of 1,4-dibenzyl-2-(hydroxymethyl)piperazine (I) with diphenyl carbonate and triethylamine in dichloromethane gives the mixed carbonate ester (II), which is treated with refluxing diethylamine to yield the carbamate ester (III). The deprotection of (III) with H2 over Pd/C in ethanol/HCl affords N,N-diethylcarbamic acid piperazin-2-ylmethyl ester (IV), which is finally condensed with 3,4,5-trimethoxybenzoyl chloride (V) by means of triethylamine in dichloromethane.