Synthesis of isatin based N 1 -alkylated 3-β-C-glycoconjugated-oxopropylidene oxindoles as potent antiplasmodial agents.

In an attempt to develop new antimalarial drugs, we have synthesized a new class of N-alkylated 3-glycoconjugated-oxopropylidene oxindoles starting from substituted isatins and glucopyranosyl propanone via a well-known cross-aldol reaction followed by dehydration. The newly synthesized compounds were screened for their in vitro antiplasmodial activity, and among all the compounds 9g, 9f, 9b, 8d, 9d, 9c, and 9e displayed potent activity with the IC50 values in the range of 0.1–0.3 μM against Chloroquine (CQ) sensitive Pf3D7 strain, while compounds 9d, 9b, 9e, 8c, 8f, 9c, and 9a have shown promising activity having IC50 values in 0.1–0.4 μM range against CQ resistant PfK1 strain, which is even better than the standard drug chloroquine with IC50 value of 0.5 μM.