Synthesis of three classes of rhodacyanine dyes and evaluation of their in vitro and in vivo antimalarial activity.

Abstract Selected members of three classes of rhodacyanine dyes, [0, 0]-, [1, 0]-, and [0, 0, 0]-rhodacyanines, were synthesized and their in vitro antimalarial activities against Plasmodium falciparum K1 (chloroquine-resistant strain) as well as their in vivo activities against P. berghei in mice were determined. The novel [0, 0, 0]-rhodacynines, 3e and 3h , possessing a benzothiazole moiety, were shown to have highly promising antimalarial activities in vivo. Moreover, the [0, 0, 0]-rhodacyanines were found to be orally bioavailable.