Synthesis, biological evaluation, and molecular docking studies of novel pyrazole, pyrazoline‐clubbed pyridine as potential antimicrobial agents

Design, synthesis, X-ray crystal structures, anticancer, DNA binding, and molecular modelling studies of pyrazole-pyrazoline hybrid derivatives

We have designed and synthesized three pyrazole analogs (4, 5a, 5b), pyrazole-based chalcones (6a-6d) and (8a-8h), and N-formyl/acetyl 1,3,5-trisubstituted pyrazoline analogs (7a-7d), (9a-9d). FT-IR, 1H, 13C NMR, and mass spectrometry techniques were used to describe the structures of all the synthesized analogs. The single crystal X-ray method was used to identify the molecular structure of derivatives 4 and 5a. All synthesized analogs were screened by MTT assay on two cancer cell lines, the human lung cancer cell line (A549) and cervical cancer cell line (HeLa). Among all compounds, analog 9d demonstrates significant anticancer activity against HeLa (IC50 = 23.6 μM) and A549 (IC50 = 37.59 μM). The non-interactive interaction of active compound (9d) with Calf thymus DNA (Ct-DNA) has been investigated through various methods, such as UV-vis absorption, emission, cyclic voltammetry and circular dichroism. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical has been used to measure the antioxidant capacity of the pyrazoline derivative (9d). The outcomes showed that active analog has significant antioxidant activity. In addition, MD simulation of the EGFR tyrosine kinase protein-ligand complex was performed at a time scale of 100 ns. The MMGBSA data of ligand-protein complex are showed stable interactions up to 100 ns.

Synthesis, Characterization, Antitubercular Activity, and Molecular Docking Studies of Pyrazolylpyrazoline-Clubbed Triazole and Tetrazole Hybrids

To increase the antitubercular potency, we synthesized a series of novel pyrazolylpyrazoline derivatives (9a-p) using the one-pot multicomponent reaction of the substituted heteroaryl aldehyde (3a,b), 2-acetyl pyrrole/thiazole (4a,b), and substituted hydrazine hydrates (5-8) in the presence of base NaOH as a catalyst in ethanol as the solvent at room temperature. Substituted heteroaryl aldehyde (3a,b) was synthesized from 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-methyl-carbaldehyde on protection with ethylene glycol followed by treatment with 4-amino triazole/5-amino tetrazole and then deprotection using acid. The salient features of the green protocol are the one-pot reaction, shorter reaction time, and straightforward workup procedure. All of the compounds were tested against Mycobacterium tuberculosis H₃₇Rv, wherein compounds 9i, 9k, 9l, 9o, and 9p were found to be most effective. The structures of newly synthesized compounds were determined using spectral methods. Furthermore, molecular docking investigations into the active site of mycobacterial InhA yielded well-clustered solutions for these compounds' binding modalities producing a binding affinity in the range from -8.884 to -7.113. Theoretical results were in good accord with the observed experimental values. The docking score of the most active compound 9o was found to be -8.884, and the Glide energy was -61.144 kcal/mol. and it was found to accommodate well into the active site of InhA, engaging in a network of bonded and nonbonded interactions.

A study on the cellular and cytotoxic effects of S and Se heterocycles on the myeloid leukemia cell line PLB-985

This paper describes the synthesis of several halogenated S and Se heterocycles and tests their biological activity by measuring the effects on the myeloid leukemia cell line, PLB-985 cells. We report that select compounds exhibit significant increases in mitochondria membrane potential and increased oxidative stress in PLB-985 cells. Our results contribute to the foundational knowledge of different S and Se containing compounds and their possible impacts on human cells.

Oxadiazole: A highly versatile scaffold in drug discovery

As a pharmacologically important heterocycle, oxadiazole paved the way to combat the problem associated with the confluence of many commercially available drugs with different pharmacological profiles. The present review focuses on the potential applications of five-membered heterocyclic oxadiazole derivatives, especially 1,2,4-oxadiazole, 1,2,5-oxadiazole, and 1,3,4-oxadiazole, as therapeutic agents. Designing new hybrid molecules containing the oxadiazole moiety is a better solution for the development of new drug molecules. The designed molecules may accumulate a biological profile better than those of the drugs currently available on the market. The present review will guide the way for researchers in the field of medicinal chemistry to design new biologically active molecules based on the oxadiazole nucleus. Antitubercular, antimalarial, anti-inflammatory, anti-HIV, antibacterial, and anticancer activities of various oxadiazoles have been reviewed extensively here.

A Review of the Recent Development in the Synthesis and Biological Evaluations of Pyrazole Derivatives

Pyrazoles are five-membered heterocyclic compounds that contain nitrogen. They are an important class of compounds for drug development; thus, they have attracted much attention. In the meantime, pyrazole derivatives have been synthesized as target structures and have demonstrated numerous biological activities such as antituberculosis, antimicrobial, antifungal, and anti-inflammatory. This review summarizes the results of published research on pyrazole derivatives synthesis and biological activities. The published research works on pyrazole derivatives synthesis and biological activities between January 2018 and December 2021 were retrieved from the Scopus database and reviewed accordingly.