Sb(V) Kaempferol and Quercetin Derivative Complexes: Synthesis, Characterization and Antileishmanial Activities

Abstract

Background: Recent studies on Leishmaniasis treatment have confirmed the antiparasitic effects of flavonols and organic antimony pentavalent [(Sb(V)] complexes. Objectives: This study aimed to identify new Sb(V) complexes by combining the benefits of antimonials and flavonols as well as by optimizing their properties. Methods: Kaempferol and quercetin peracetate were prepared using acetic anhydride in pyridine. By performing regioselective synthesis, 7-O-paramethylbenzyl as an electron-donating group and 7-O-paranitrobenzyl as an electron-withdrawing group were added to quercetin, and, then, the synthesis of Sb(V) kaempferol and quercetin derivative complexes were performed using SbCl5 solution in glacial acetic acid. The structures were confirmed by UV, ESI mass, IR, 1H-, and 13C-NMR spectral data, and the Stoichiometry of the ligand-metal complex by the mole ratio method. Computational molecular modeling was conducted using the Gaussian program. Results: The structures were confirmed based on the results from UV, nuclear magnetic resonance (NMR), and electrospray ionization (ESI) mass analyses (3-12). Among the produced compounds, 11 and 12 as newly described, and other compounds as pre-defined compounds were identified. According to the results from biological test, kaempferol triacetate with more lipophilicity showed the highest anti-promastigote activity with an IC50 value of 14.93 ± 2.21 µM. As for anti-amastigote activity, despite the differences, all antimony complexes showed anti-amastigote effects in vitro with IC50 values of 0.52 to 14.50 µM. Conclusions: All flavonol Sb(V) complexes showed higher activity compared to meglumine antimonate in anti-amastigote effect. Inside the host macrophages, by breaking down the complex into antimony and quercetin or kaempferol analogs, the observed antiparasitic effects may have been related to both Sb(V)/Sb(III) conversion and flavonoid antileishmanial activities.

Assessment of the potential prophylactic and therapeutic effects of kaempferol on experimental Trichinella spiralis infection

“…The effect of KPF on the developmental stages of T. spiralis has not been previously investigated, although the parasiticidal effect of KPF has been demonstrated in other parasitic infections. KPF has been shown to possess a broad range of pharmacological and biological activities against Entamoeba histolytica , Giardia duodenalis , Leishmania and malaria parasites (Pérez-González et al , 2017; Somsak et al , 2018; Argüello-García et al , 2020; Abdeyazdan et al , 2022). Moreover, KPF has demonstrated anthelmintic activity against schistosomiasis (Zhou et al , 2013).…”

“…Various studies have documented KPF's anti-parasitic effect, particularly in protozoa such as Entamoeba histolytica , Giardia duodenalis , Leishmania spp. and malaria parasites (Pérez-González et al , 2017; Somsak et al , 2018; Argüello-García et al , 2020; Abdeyazdan et al , 2022). Furthermore, KPF's anti-helminthic activity has been demonstrated against schistosomiasis (Zhou et al , 2013).…”

[Cell@Al2O3(HEPiPY)]DCA: A Cellulose Supported Ionic Liquid Catalyst for Synthesis of 11 b,12‐dihydro‐6H,13Hbenzo[5,6][1,3]oxazino[3,4‐a]quinazoline‐6,13‐dione along with in silico assessments

“…3 b was found at the highest strength of interactions with the target and 3 g was found at the lowest strength of infarctions. This in silico assessment was done by benefits of using computational tool for investigating the complicated biological systems, in which the results could reveal the structural and electronic features of molecular compounds and their tendency of participating in interactions with the biological targets [38–40] . As a consequence, all 3a–3i ligands were seen suitable for participating in interactions with the VEGFR‐2 target with more or less significant strengths of ligand‐target complex formations in comparison with each other revealing insights into the development of VEGFR‐2 inhibitors.…”

GC-MS and Bioassay-Guided Isolation of Xanthones from <i>Mammea siamensis</i>

“…Medicinal plants are employed as ingredients in several traditional remedies due to their phytochemical metabolites, such as terpenoids, flavonoids, alkaloids, and polyphenols. These significant bioactive components revealed diverse efficiency, for example, anticancer [1][2][3], antioxidant [3][4][5], antimicrobial [4][5][6], and antileishmanial activities [5,7]. Accordingly, various Thai medicinal plants are famous for acting as active elements in several folk medicines, including Mammea siamensis [8][9].…”