Synthesis and biological activities of dibenzyl dipiperazine diquaternary ammonium salts

Twenty new 4,4'-dibenzyl-1,1'-(decane-1,5-diyl)-piperazinium dihalides 6a-1 and 1,1'-dibenzyl-1,1'-(decane-1,5-diyl)piperazinium dihydrochloride dihal ides 6a-1 were prepared and evaluated for their analgesic, sedative and ant i-inflammatory activities. Structure activity relationship studies indicate d that the compounds 6c (Ar = 4-NO2C6H5) and 6k (Ar = 3-Me-C6H5) exhibited higher activities than others. Compared with the corresponding compounds 6k and 6l, the presence of benzoyl in the compound 5k and 5l exerted a contra ry influence on the activities. 5h and 6h show the highest anti-inflammator y activity (59%, dose 20 mg/kg and 48%,dose 1 mg/kg) in the series 5 and 6, respectively.