Synthesis, Antitrypanosomal and Antimycobacterial Activities of Coumarin N-acylhydrazonic Derivatives

Synthesis and activity of benzimidazole N-Acylhydrazones against Trypanosoma cruzi, Leishmania amazonensis and Leishmania infantum

In this study, we present the design, synthesis, and cytotoxic evaluation of a series of benzimidazole N-acylhydrazones against strains of T. cruzi (Y and Tulahuen) and Leishmania species (L. amazonensis and L. infantum). Compound (E)-N'-((5-Nitrofuran-2-yl)methylene)-1H-benzo[d]imidazole-2-carbohydrazide demonstrated significant activity against both trypomastigote and amastigote forms (Tulahuen strain), with an IC50/120 h of 0.033 μM and a selectivity index (SI) of 7680. This represents a potency 46 times greater than that of benznidazole (IC50/120 h = 1.520 μM, SI = 1390). Another compound (E)-N'-(2-Hydroxybenzylidene)-1H-benzo[d]imidazole-2-carbohydrazide showed promising activity against both trypomastigote and amastigote forms (Tulahuen strain), with an IC50/120 h of 3.600 μM and an SI of 14.70. However, its efficacy against L. infantum and L. amazonensis was comparatively lower. These findings provide valuable insights for the development of more effective treatments against Trypanosoma cruzi.

New coumarin linked thiazole derivatives as antimycobacterial agents: Design, synthesis, enoyl acyl carrier protein reductase (InhA) inhibition and molecular modeling

Tuberculosis is a global serious problem that imposes major health, economic and social challenges worldwide. The search for new antitubercular drugs is extremely important which could be achieved via inhibition of different druggable targets. Mycobacterium tuberculosis enoyl acyl carrier protein reductase (InhA) enzyme is essential for the survival of M. tuberculosis. In this investigation, a series of coumarin based thiazole derivatives was synthesized relying on a molecular hybridization approach and was assessed against thewild typeMtb H37Rv and its mutant strain (ΔkatG) via inhibiting InhA enzyme. Among the synthesized derivatives, compounds 2b, 3i and 3j were the most potent against wild type M. tuberculosis with MIC values ranging from 6 to 8 μg/ mL and displayed low cytotoxicity towards mouse fibroblasts at concentrations 8-13 times higher than the MIC values. The three hybrids could also inhibit the growth of ΔkatGmutant strain which is resistant to isoniazid (INH). Compounds 2b and 3j were able to inhibit the growth of mycobacteria inside human macrophages, indicating their ability to penetrate human professional phagocytes. The two derivatives significantly suppress mycobacterial biofilm formation by 10-15 %. The promising target compounds were also assessed for their inhibitory effect against InhA and showed potent effectiveness with IC50 values of 0.737 and 1.494 µM, respectively. Molecular docking studies revealed that the tested compounds occupied the active site of InhA in contact with the NAD+ molecule. The 4-phenylcoumarin aromatic system showed binding interactions within the hydrophobic pocket of the active site. Furthermore, H-bond formation and π -π stacking interactions were also recorded for the promising derivatives.

Crystal structure, Hirshfeld surface analysis and Pixel calculations of the monohydrate of (E)-3-(2-hydroxy-5-methoxyphenyl)-1-(2-hydroxy-4-methoxyphenyl)prop-2-en-1-one: occurrence of π interactions

A detailed structural analysis has been carried out on the monohydrate of (E)-3-(2-hydroxy-5-methoxyphenyl)-1-(2-hydroxy-4-methoxyphenyl)prop-2-en-1-one, 1·H 2 O. The molecule, 1, shows a small deviation from planarity with an interplanar angle between the phenyl groups of 13.32(6)°. Classical O–H⋯O hydrogen bonds involving the water molecule play significant roles in determining the overall structure. The chalcone molecules in the structure are linked directly by C–H⋯O and off-set face-to-face π⋯π intermolecular interactions, as well as indirectly via interactions involving the water molecule in an elaborate spiralling hydrogen bonding scheme. The relative contributions of various intermolecular contacts were investigated using Hirshfeld surface analysis and the associated two dimensional fingerprint plots. Pairs of molecules were identified in the crystal structure using the Pixel method. The Pixel lattice energy calculations revealed that the dispersion and the Coulombic components were the major contributors to the packing stabilization. Comparisons were made between the structures of 1·H 2 O and hydroxylated (E)-3-(2-hydroxyphenyl)-1-phenyl-prop-2-en-1-one derivatives, in particular in regards to the participation of π interactions.