4-Aminobicyclo[2.2.2|octan-2-yl 4-aminobutanoates with antiprotozoal activity

A new series of 4-aminobicyclo[2.2.2]octan-2-yl 4-aminobutanoates have been prepared. Their activities against the multiresistant K1 strain of Plasmodium falciparum and Trypanosoma brucei rhodesiense were determined and compared with the results for ethanoate and propanoate analogs. Several structure–activity relationships were detected. The antiprotozoal activities were influenced by the kind of both amino substituents and by the chain length of the acid moiety. The butanoates exhibited higher antiplasmodial potency than their analogs with shorter chain length. Representative compounds of the propanoate and butanoate series were the most active antitrypanosomal compounds.