Design, Synthesis, Anti-Tubercular Evaluation and Teratogenicity Studies of Furanyl Pyrazolo[3,4-b] Quinoline-5-Ones

Quinoline analogs: multifaceted heterocyclic compounds with varied synthetic strategies and potent antitubercular properties

Tuberculosis cases have continuously increased by 64% over the last nine years, from 2014 to 2023. Approximately 33% of the global population is affected by TB. It is a bacterial disease, and Mycobacterium tuberculosis is the most common bacteria that affects the lungs of human beings during the infection. Other hazardous bacterial species causing tuberculosis are M. pinnipedii, M. canettii, M. caprae, M. bovis, M. africanum, and M. microti. TB symptoms in TB-infected patients include fever, chest pain, weight loss, and fatigue. Depending on the stage of infection, the treatment for TB can take approximately six months to two years. Quinoline comprises a pyridine ring fused with a benzene ring, and both these rings share two adjacent carbon atoms and can take part in electrophilic substitution reactions. Quinoline-based heterocyclic compounds are attracting substantial interest owing to their vital role as a class of synthetic and natural molecules. Quinoline and its derivatives display various biological activities, including anti-TB, anticonvulsant, antibiotic, antifungal, antimalarial, antipsychotic, antihypertensive, antileishmanial, antioxidant, tyrosine kinase inhibitory, anti-inflammatory, anticancer, anti-asthmatic, cardiotonic, anthelmintic, antiprotozoal, anti-HIV, and anti-Alzheimer effects. Some fused analogs of quinoline, such as graveolinine, ciprofloxacin, kokusaginine, bedaquiline, levofloxacin, moxifloxacin, and mefloquine, are commercially available as antitubercular drugs. There are various methods available to synthesize quinoline-containing antitubercular drugs. In this review paper, we present three types of synthetic methods in which substituted quinolines, substituted anilines, and miscellaneous starting materials are used and outline MIC values for all the synthesized compounds to signify their anti-TB activity.

Quinoline hybrid derivatives as effective structural motifs in the treatment of tuberculosis: Emphasis on structure-activity relationships

Mycobacterium tuberculosis (MTB/Mtb) is the causative agent of tuberculosis (TB), a highly infectious serious airborne illness. TB usually affects the lungs, in 25 % of patients (children or immune impaired adults), mycobacteria can enter the blood stream and infect other bodily areas such the meninges, pleura, lymphatic system, genitourinary system, bones, and joints. Currently, the most challenging aspect of treating this illness is the ineffectiveness of the most potent first-line anti-TB medications, isoniazid, rifampin, pyrazinamide, and ethambutol, which can result in multidrug-resistant TB (MDR-TB), extensively drug-resistant TB (XDR-TB), and in rare instances, completely drug-resistant TB (TDR-TB). As a result, finding new pharmaceutical compounds to treat these diseases is a significant challenge for the scientific community. A number of bio-active molecules have been investigated in this quest, including quinoline, which is considered a promising candidate for the development of TB drugs. It is known that quinoline are low in toxicity and have a wide range of pharmacological properties. Researchers have investigated quinoline scaffolds as anti-TB drugs based on their biological spectrum. The objective of this review is to examine the recent development of quinoline and its structural characteristics crucial to its antitubercular (anti-TB) activity. A molecular analog of the TB treatment can be designed and identified with this information. As a result, future generation quinoline-based anti-TB agents with greater potency and safety can also be explored.

Molecular docking, ADME properties and synthesis of thiophene sulfonamide derivatives

This study investigates the drug-like properties of target molecules containing thiophene sulfonamide groups (7a-7s) using computational molecular docking techniques. The binding interactions of these derivatives were assessed using protein 2NSD (Enoyl acyl carrier protein reductase InhA, complexed with N-(4-methylbenzoyl)-4-benzylpiperidine, PDB DOI: 10.2210/pdb2NSD/pdb) as the receptor. Molecular docking results revealed notable docking scores for all compounds, ranging from -6 to -12 kcal/mol. Compounds 7e, 7i, and 7f, in particular, demonstrated impressive glide scores (>11 kcal/mol) and were selected for further analysis through molecular dynamics simulations, which provided deeper insights into their dynamic behavior and stability. The drug-like properties of these molecules were evaluated based on Lipinski's Rule of Five and ADME (Absorption, Distribution, Metabolism, and Excretion) criteria and compared with known drugs. Additionally, we synthesized these target molecules (7a-7s) using Suzuki-Miyaura coupling with a nickel catalyst replacing palladium. The chemical structures of the synthesized compounds were confirmed through elemental analysis, LC-MS,1H-NMR, and 13C-NMR spectroscopy.

Embryonic and larval zebrafish models for the discovery of new bioactive compounds against tuberculosis

Tuberculosis (TB) is a world health challenge the treatment of which is impacted by the rise of drug-resistant strains. Thus, there is an urgent need for new antitubercular compounds and novel approaches to improve current TB therapy. The zebrafish animal model has become increasingly relevant as an experimental system. It has proven particularly useful during early development for aiding TB drug discovery, supporting both the discovery of new insights into mycobacterial pathogenesis and the evaluation of therapeutical toxicity and efficacy in vivo. In this review, we summarize the past two decades of zebrafish-Mycobacterium marinum research and discuss its contribution to the field of bioactive antituberculosis therapy development.

In silico drug design strategies for discovering novel tuberculosis therapeutics

INTRODUCTION

Tuberculosis remains a significant concern in global public health due to its intricate biology and propensity for developing antibiotic resistance. Discovering new drugs is a protracted and expensive endeavor, often spanning over a decade and incurring costs in the billions. However, computer-aided drug design (CADD) has surfaced as a nimbler and more cost-effective alternative. CADD tools enable us to decipher the interactions between therapeutic targets and novel drugs, making them invaluable in the quest for new tuberculosis treatments.

AREAS COVERED

In this review, the authors explore recent advancements in tuberculosis drug discovery enabled by in silico tools. The main objectives of this review article are to highlight emerging drug candidates identified through in silico methods and to provide an update on the therapeutic targets associated with Mycobacterium tuberculosis.

EXPERT OPINION

These in silico methods have not only streamlined the drug discovery process but also opened up new horizons for finding novel drug candidates and repositioning existing ones. The continued advancements in these fields hold great promise for more efficient, ethical, and successful drug development in the future.