Designing, molecular docking, and dynamics simulations studies of 1,2,3-triazole clamped Uracil-Coumarin hybrids against EGFR tyrosine kinase

Since the last decade, hybrid drug strategies have attracted many researchers for their improved anti-cancer potential incomparison to single drug components. Complying to this approach, 28 novel Uracil–Coumarin hybrids with differentsized linkers (2–5 carbon atoms) and substituents were designed to occupy the active site of protein epidermal growthfactor receptor (EGFR) tyrosine kinase (Protein Data Bank ID: 1M17). Molecular docking studies were performedfor all ligands (A1-D7) to identify the potential candidate using Schrödinger software. The relative binding affinity ofhybrids toward EGFR was compared with standard Erlotinib on the basis of gScore and Emodel score. Positively, allthe hybrids docked inside the cavity and showed significant interactions, compounds A6, A2, and A7 with short-chainlinker (two carbon atoms) and halogen substituents were found to have more interactions and better docking score thanstandard Erlotinib. The visualization results depicted that compound A6 showed the highest affinity and formed thebest binding pose to the target EGFR with gScore = −8.891 kcal/mol and Emodel score = −100.744 in comparison tostandard Erlotinib (gScore of −8.538 kcal/mol and Emodel score = −80.588). Moreover, a molecular dynamics studyalso reveals that ligand A6 forms a stable complex with root mean square deviation (RMSD) of 0.3 nm and the plateauphase started just after 10 ns (time). Hence, the present research provides computational insights of Uracil–Coumarinhybrids as potential ligands against EGFR tyrosine kinase and in future in vitro investigations of these hybrids mayprove their therapeutic potential against cancer.

Characterisation of the in vitro activity of a Nitazoxanide-N-methyl-1H-benzimidazole hybrid molecule against albendazole and nitazoxanide susceptible and resistant strains of Giardia intestinalis and its in vivo giardicidal activity

BACKGROUND It was previously demonstrated that CMC-20, a nitazoxanide and N-methyl-1H-benzimidazole hybrid molecule, had higher in vitro activity against Giardia intestinalis WB strain than metronidazole and albendazole and similar to nitazoxanide. OBJETIVES To evaluate the in vitro activity of CMC-20 against G. intestinalis strains with different susceptibility/resistance to albendazole and nitazoxanide and evaluate its effect on the distribution of parasite cytoskeletal proteins and its in vivo giardicidal activity. METHODS CMC-20 activity was tested against two isolates from patients with chronic and acute giardiasis, an experimentally induced albendazole resistant strain and a nitazoxanide resistant clinical isolate. CMC-20 effect on the distribution of parasite cytoskeletal proteins was analysed by indirect immunofluorescence and its activity was evaluated in a murine model of giardiasis. FINDINGS CMC-20 showed broad activity against susceptible and resistant strains to albendazole and nitaxozanide. It affected the parasite microtubule reservoir and triggered the parasite encystation. In this process, alpha-7.2 giardin co-localised with CWP-1 protein. CMC-20 reduced the infection time and cyst load in feces of G. muris infected mice similar to albendazole. MAIN CONCLUSIONS The in vitro and in vivo giardicidal activity of CMC-20 suggests its potential use in the treatment of giardiasis.

Characterisation of the in vitro activity of a Nitazoxanide-N-methyl-1H-benzimidazole hybrid molecule against albendazole and nitazoxanide susceptible and resistant strains of Giardia intestinalis and its in vivo giardicidal activity

BACKGROUND It was previously demonstrated that CMC-20, a nitazoxanide and N-methyl-1H-benzimidazole hybrid molecule, had higher in vitro activity against Giardia intestinalis WB strain than metronidazole and albendazole and similar to nitazoxanide. OBJETIVES To evaluate the in vitro activity of CMC-20 against G. intestinalis strains with different susceptibility/resistance to albendazole and nitazoxanide and evaluate its effect on the distribution of parasite cytoskeletal proteins and its in vivo giardicidal activity. METHODS CMC-20 activity was tested against two isolates from patients with chronic and acute giardiasis, an experimentally induced albendazole resistant strain and a nitazoxanide resistant clinical isolate. CMC-20 effect on the distribution of parasite cytoskeletal proteins was analysed by indirect immunofluorescence and its activity was evaluated in a murine model of giardiasis. FINDINGS CMC-20 showed broad activity against susceptible and resistant strains to albendazole and nitaxozanide. It affected the parasite microtubule reservoir and triggered the parasite encystation. In this process, alpha-7.2 giardin co-localised with CWP-1 protein. CMC-20 reduced the infection time and cyst load in feces of G. muris infected mice similar to albendazole. MAIN CONCLUSIONS The in vitro and in vivo giardicidal activity of CMC-20 suggests its potential use in the treatment of giardiasis.