Propargyl Alcohol-Derived 1,2,3-Triazoles Demonstrate Antiplasmodial Activity

This research demonstrates computationally guided synthesis and antiplasmodial properties of novel propargyl alcohol-derived 1,2,3-triazoles namely: 1-(3-fluoro-2-nitrophenyl)-1H-1,2,3-triazol-1-yl) methanol (M32/S1), (1-(o-tolyl)-1H-1,2,3-triazol-5-yl) methanol (M33/S2), (1-(3-nitrophenyl)-1H-1,2,3-triazol-4-yl) methanol (M34/S3), (1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl) methanol (M35/S4), and 4-(4-(hydroxymethyl)-1H-1,2,3-triazol-1-yl) benzoic acid (M36/S5). Of 36 computationally simulated triazoles, these were synthesized based on high binding energies and favorable docking scores. M36/S5 (moderate binding score) was synthesized to verify correlation of hydrogen bonding deduced from molecular docking to the observed antiplasmodial activity. M32/S1, M33/S2, M34/S3, M35/S4 and M36/S5 exhibited highest binding affinity scores/MMGBSA of (−6.50/−37.81), (−6.20/−32.26), (−6.20/−33.20), (−6.00/−37.47) and (−5.52/−22.93) respectively. In vitro screening using SYBR green assay of M32/S1, M33/S2, M34/S3 and M35/S4 against Plasmodium strains (DD2, 3D7) demonstrated potent antimalarial activity comparable to artesunate. Cytotoxicity was studied against human erythrocytes by MTT assay, and no hemolysis was observed. In vivo studies showed that the five studied compounds showed antimalarial action against Plasmodium berghei NK65-infected mice. Docking analysis against Plasmepsin II demonstrated molecular interactions with the catalytic residues in the active site of the binding pocket comparable to chloroquine. In vivo studies showed that the five compounds demonstrated antimalarial action against Plasmodium berghei NK65 infected mice with M32/S1 as the most potent. M32/S1 identified as the most promising compound for optimization.