Abstract
Novel 54 pyrrolyl acetohydrazide analogues were designed, synthesized and screened for antitubercular activity against InhA. Enoyl-ACP reductase/InhA one of the significant enzymes implicated in type II FAS (fatty acid synthase) biosynthetic pathway of bacterial outer cell membrane, in addition Mycobacterium tuberculosis H37Rv inhibition potency has proven to be one of the most promising drug target used for designing and testing against TB. In silico molecular modeling was achieved using Surflex-docking method to recognize important binding sites of the enoyl-ACP reductase. 3D-QSAR studies like CoMFA and CoMSIA approaches were studied to create 3D-QSAR depictions for InhA inhibitors. Based on docking results the synthesized molecules are oriented towards the core of the active site. The pyrolyl acetohydrazides exhibited one or two H-bonding connections with InhA enzyme. Molecule 8l (MIC 0.4 μg/mL, InhA- 70% at 50 μM) showed H-bonding connections with Tyr158 and NAD+ in a similar mode to that of ligand pyrrolidine carboxamide. The tested molecules also showed good antibacterial (Escherichia coli, Staphylococcus aureus) activity (MIC 0.4–25 μg/mL), while the study against A549 lung adenocarcinoma cell line confirms nontoxic nature of the reported molecules. The QSAR model from CoMFA and CoMSIA through the database configuration showed the most excellent data. The prognostic ability of CoMFA and CoMSIA representations was developed by a test set of 15 molecules that produced cross validated correlation coefficients (q2) of 0.642 and 0.701, respectively. This study gives insight into structural requirement needed for the development of more active InhA inhibitors through in silico approach.
Antitubercular activity of novel series of pyrrole derivatives was analyzed. Molecular model was constructed using Surflex-Dock and 3D-QSAR studies using enoyl-ACP reductase from Mycobacterium tuberculosis. [Display omitted]
•Inhibitors of mycobacterial Enoyl ACP reductase were designed using in silico approach.•54 novel pyrrole scaffolds were designed and synthesized.•Surflex docking studies were carried out to understand the binding affinity of the compounds.•All the reported inhibitors were active against Mycobacterium tuberculosis, Staphylococcus aureus, Eschrichia coli.•Compound 7q could further explored as lead to develop newer antimycobacterial agent.