Potential Antimalarials. V. 4-(7′-Trifluoromethylquinolin-4′-Ylamino)Phenols, 4-[2′,7′ and 2',8′-Bis(Trifluoromethyl)Quinolin-4′-Ylamino]Phenols and N4-Substituted 2,7-(and 2,8-)Bis(Trifluoromethyl)-Quinolin-4-Amines

Mono- and di-Mannich bases of 4-(7′-trifluoromethylquinolin-4′- ylamino )phenol and its 2′,7′- and 2′,8′-bis( trifluoromethyl ) analogues, for example 2,6-bis(piperidin-1′-ylmethyl)-4-(7′-trifluoromethyl- quinolin-4′-ylamino)phenol, have been prepared. The Mannich bases from 4-(7′-trifluoromethyl-quinolin-4′-ylamino)phenol showed significant antimalarial activity when injected intraperitoneally in a single dose of 100 mg/kg to mice infected with Plasmodium vinckei vinckei ; those from its 2′,7′- and 2′,8′-bis( trifluoromethyl ) analogues did not show appreciable activity. Some N4-substituted 2,7(and 2,8)- bis ( trifluoromethyl )quinolin-4-amines with aliphatic side chains were also prepared but were inactive. The blood schizontocidal activity of mefloquine was not retained in the 2,8-bis( trifluoromethyl )-quinolin-4-amines prepared here.