Synthesis and antiplasmodial activity of purine-based C-nucleoside analogues.

A series of homologous C-nucleoside mimics have been synthesized via an efficient and facile synthetic protocol involving the conjugate addition of purine to sugar derived olefinic ester in good yields. The synthesized compounds were evaluated for their antiplasmodial activity in vitro against both the CQ-sensitive and resistant strains of P. falciparum. Interestingly, all the synthesized nucleoside analogs exhibited an IC50 of <5 µM, while compounds 22a, 23a, and 23b showed promising antiplasmodial activity with an IC50 of 1.61, 0.88, and 1.01 µM against the CQ-sensitive Pf3D7 strain and 1.14, 1.01, and 2.57 µM against the CQ-resistant PfK1 strain, respectively.

Synthesis and antiplasmodial activity of glyco-conjugate hybrids of phenylhydrazono-indolinones and glycosylated 1,2,3-triazolyl-methyl-indoline-2,3-diones.

A small library of 36 new glycohybrids of phenylhydrazono-indolinones was synthesized employing glycosylated 1,2,3-triazolyl-methyl-indoline-2,3-diones and different phenylhydrazines via acid catalyzed reaction. All the compounds were screened for their antiplasmodial activity in vitro. Compounds 6c, 7c, and 7b showed significant activity with the IC50 values 1.27, 1.64 and 1.96 µM, respectively against CQ sensitive Pf3D7 strain while compounds 7b and 6f showed good activity with IC50 1.61 and 1.93 µM, respectively against CQ resistant PfK1 strain.