Medicinal Chemistry - Volume 20, Issue 9, 2024

Vascular endothelial growth factor receptor-2 (VEGFR-2) is a critical protein involved in tumor progression, making it an attractive target for cancer therapy.

This study aimed to synthesize and evaluate novel thieno[2,3-d]pyrimidine analogues as potential anticancer VEGFR-2 inhibitors.

The thieno[2,3-d]pyrimidine analogues were synthesized following the pharmacophoric features of VEGFR-2 inhibitors. The anticancer potential was assessed against PC3 and HepG2 cell lines. The VEGFR-2 inhibition was evaluated through IC50 determination. Cell cycle analysis and apoptosis assays were performed to elucidate the mechanisms of action. Molecular docking, molecular dynamics simulations, MM-GBSA, and PLIP studies were conducted to investigate the binding affinities and interactions with VEGFR-2. Additionally, in silico ADMET studies were performed.

Compound 8b demonstrated significant anti-proliferative activities with IC50 values of 16.35 µM and 8.24 µM against PC3 and HepG2 cell lines, respectively, surpassing sorafenib and exhibiting enhanced selectivity indices. Furthermore, compound 8b showed an IC50 value of 73 nM for VEGFR-2 inhibition. Cell cycle analysis revealed G2-M phase arrest, while apoptosis assays demonstrated increased apoptosis in HepG2 cells. Molecular docking and dynamic simulations confirmed the binding affinity and interaction of compound 8b with VEGFR-2, supported by MM-GBSA and PLIP studies. In silico ADMET studies indicated the drug development potential of the synthesized thieno[2,3-d]pyrimidines.

The study highlights compound 8b as a promising VEGFR-2 inhibitor with potent anti-proliferative activities. Its mechanism of action involves cell cycle arrest and induction of apoptosis. Further, molecular docking and dynamic simulations support the strong binding affinity of compound 8b to VEGFR-2.

Drug resistance to existing antimicrobial drugs has become a serious threat to human health, which highlights the need to develop new antimicrobial agents.

In this study, a new set of 3-hydroxypyridine-4-one derivatives (6a-j) was synthesized, and the antimicrobial effects of these derivatives were evaluated against a variety of microorganisms using the microdilution method. The antimicrobial evaluation indicated that compound 6c, with an electron-donating group -OCH3 at the meta position of the phenyl ring, was the most active compound against S. aureus and E. coli species with an MIC value of 32 µg/mL. Compound 6c was more potent than ampicillin as a reference drug.

The in vitro antifungal results showed that the studied derivatives had moderate effects (MIC = 128-512 µg/mL) against C. albicans and A. niger species. The molecular modeling studies revealed the possible mechanism and suitable interactions of these derivatives with the target protein.

The obtained biological results offer valuable insights into the design of more effective antimicrobial agents.

Rhipicephalus microplus, an important cattle ectoparasite, is responsible for a substantial negative impact on the economy due to productivity loss. The emergence of resistance to widely used commercial acaricides has sparked efforts to explore alternative products for tick control.

To address this challenge, innovative solutions targeting essential tick enzymes, like glutathione S-transferase (GST), have gained attention. Dimeric flavonoids, particularly brachydins (BRAs), have demonstrated various biological activities, including antiparasitic effects. The objectives of this study were to isolate four dimeric flavonoids from Fridericia platyphylla roots and to evaluate their potential as inhibitors of R. microplus GST.

In vitro assays confirmed the inhibition of R. microplus GST by BRA-G, BRA-I, BRA-J, and BRA-K with IC50 values of 0.075, 0.079, 0.075, and 0.058 mg/mL, respectively, with minimal hemolytic effects. Molecular docking of BRA-G, BRA-I, BRA-J, and BRA-K in a three-dimensional model of R. microplus GST revealed predicted interactions with MolDock Scores of -142.537, -126.831, -108.571, and -123.041, respectively. Both in silico and in vitro analyses show that brachydins are potential inhibitors of R. microplus GST.

The findings of this study deepen our understanding of GST inhibition in ticks, affirming its viability as a drug target. This knowledge contributes to the advancement of treatment modalities and strategies for improved tick control.