Conformationally restricted anti-plasmodial chalcones

Chalcones can exist as Z- or E-isomers and it is generally anticipated that both isomers are equipotent. In order to determine the active isomer of anti-plasmodial chalcones a series of analogues locked in the Z- or the E-form were prepared and evaluated for their anti-plasmodial activity. It was shown that the Z-locked analogue was nearly inactive, whereas the E-locked analogues were equipotent to the parent chalcones, indicating that the E-isomer is the active conformation.