Mefloquine-oxazolidine derivatives: a new class of anticancer agents.

A series of 23 racemic mefloquine-oxazolidine derivatives, 4-[3-(aryl)hexahydro[1,3]oxazolo[3,4-a]pyridin-1-yl]-2,8-bis(trifluoromethyl)quinolines, derived from (R*, S*)-(±)-mefloquine and arenealdehydes, have been evaluated for their activity against four cancer cell lines (HCT-8, OVCAR-8, HL-60, and SF-295). Good cytotoxicities have been determined with IC50 values ranging from 0.59 to 4.79 μg/mL. In general compounds with aryl groups having strong electron-releasing substituents, such as HO and MeO, or electron-rich heteroaryl groups, for example imidazol-2-y-l, are active. However, other factors such as steric effects may play a role. As both the active and non-active conformations of the mefloquine-oxazolidine derivatives are similar, it is concluded that molecular conformations do not play a significant role either. This study is the first to evaluate mefloquine derivatives as antitumor agents. The mefloquine-oxazolidine derivatives are considered to be useful leads for the rational design of new antitumor agents.