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An innovative class of novel 2-aryl-5-(1-aryl-1H-pyrazol-3-yl)-1,3,4-oxadiazoles 5i–w have been synthesized from ring transformation using L-proline as an organocatalyst. This novel method using organocatalyst is a splendid example of the green reaction with improved yields. The molecular docking analysis of compounds 5i–w were investigated with enoyl-acyl carrier protein reductase (InhA) enzyme (PDB ID: 4TZK) as anti-tubercular target molecules. The docking study implied that the synthesized compounds exhibited favorable binding modes and affinity. Further, the anti-tubercular activity was investigated against Mycobacterium tuberculosis (MTB) H37Rv strain which demonstrated that the compounds 5i, 5j, 5k, and 5l exhibited excellent activity at the 6.25 µg/ml concentrations, whereas the compounds 5m, 5n, 5o, 5s, and 5w have shown the activity at 12.50 µg/ml concentration, respectively. [ABSTRACT FROM AUTHOR]

In efforts to develop new antitubercular agents, we report here the synthesis of a series of novel pyrrole hydrazine derivatives. The molecules were evaluated against inhibitors of InhA, which is one of the key enzymes involved in type II fatty acid biosynthetic pathway of the mycobacterial cell wall as well as inhibitors of Mycobacterium tuberculosis H37Rv. The binding mode of compounds at the active site of enoyl-ACP reductase was explored using the surflex-docking method. The model suggests one or two H-bonding interactions between the compounds and the InhA enzyme. Some compounds exhibited good activities against InhA in addition to promising activities against M. tuberculosis. [ABSTRACT FROM AUTHOR]

Novel pyrrolyl hydrazones and their copper complexes have been synthesized and characterized using analytical and spectral techniques to show the tetrahedral geometry for Cu(II) complexes. Biological activities of hydrazones have been assessed to understand the role of metal ion on their biological activity and the effect of pyrrolyl hydrazones. In vitro antitubercular activity against Mycobacterium tuberculosis of the metal complexes ( 13b and 13r ) exhibited the highest antitubercular activity that are quite close to rifampicin (0.4 μg/mL), giving a MIC of 0.8 μg/mL. All other compounds showed good activity with the MIC values ranging from 1.6 to 100 μg/mL. A comparative study of inhibition values of the ligands and their complexes showed higher antimicrobial activity of the complexes than the ligands. Some compounds have a good activity against InhA and in particular, compounds 12r , 13b and 13r exhibited more than 60% binding with the enzyme even at 5 μM (exhibited good IC50 upto 2.4 μM). Most of the active molecules have a very less cytotoxicity against the human lung cancer cell-line A549. The docking and 3D-QSAR studies have been carried out to provide some insights into the mechanism of action for this class of compounds. [ABSTRACT FROM AUTHOR]

Enoyl acyl carrier protein reductase (ENR) is an essential type II fatty acid synthase (FAS-II) pathway enzyme that is an attractive target for designing novel antitubercular agents. Herein, we report sixty-eight novel pyrrolyl substituted aryloxy-1,3,4-thiadiazoles synthesized by three-step optimization processes. Three-dimensional quantitative structure–activity relationships (3D-QSAR) were established for pyrrolyl substituted aryloxy-1,3,4-thiadiazole series of InhA inhibitors using the comparative molecular field analysis (CoMFA). Docking analysis of the crystal structure of ENR performed by using Surflex-Dock in Sybyl-X 2.0 software indicates the occupation of pyrrolyl substituted aryloxy 1,3,4-thiadiazole into hydrophobic pocket of InhA enzyme. Based on docking and database alignment rules, two computational models were established to compare their statistical results. The analysis of 3D contour plots allowed us to investigate the effect of different substituent groups at different positions of the common scaffold. In vitro testing of ligands using biological assays substantiated the efficacy of ligands that were screened through in silico methods. [ABSTRACT FROM AUTHOR]

In this study, new series of N'-(2-(substitutedphenoxy)acetyl)-4-(1H-pyrrol-1-yl)benzohydrazides (3a-j) 4-(2,5-dimethyl-1H-pyrrol-1-yl)-N'-(2-(substitutedphenoxy)acetyl)benzohydrazides (5a-j) were synthesized, characterized and assessed as inhibitors of enoyl ACP reductase and DHFR. Most of the compounds exhibited dual inhibition against the enzymes enoyl ACP reductase and DHFR. Several synthesized substances also demonstrated significant antibacterial and antitubercular properties. A molecular docking analysis was conducted in order to determine the potential mechanism of action of the synthesized compounds. The results indicated that there were binding interactions seen with the active sites of dihydrofolate reductase and enoyl ACP reductase. Additionally, important structural details were identified that play a critical role in sustaining the dual inhibitory activity. These findings were useful for the development of future dual inhibitors. Therefore, this study provided strong evidence that several synthesized molecules could exert their antitubercular properties at the cellular level through multi-target inhibition. By shedding light on the mechanisms through which these compounds exert their inhibitory effects, this research opens up promising avenues for the future development of dual inhibitors with enhanced antibacterial and antitubercular properties. The study's findings underscore the importance of multi-target approaches in drug design, providing a strong foundation for the design and optimization of novel compounds that can effectively target bacterial infections at the cellular level. [ABSTRACT FROM AUTHOR]

2-Propargylthiobenzimidazole 1 , 4-bromomethyl coumarins/1-aza-coumarins 2 / 3 and sodium azide have been reacted in one pot under Click chemistry conditions to give exclusively 1,4-disubstituted triazoles 5a – n . Anti-tubercular assays against M. tuberculosis (H 37 Rv) coupled with in silico molecular docking studies indicated that dimethyl substituents 5c and 5d showed promising activity with higher C-score values. [ABSTRACT FROM AUTHOR]

A series of new Coumarin hydrazone oxime scaffolds were synthesised as potential anti‐TB agents. The structures of the scaffolds were confirmed by spectroscopic and analytical techniques. X‐ray crystallography confirmed the structure of compound 6‐methyl‐4‐((((Z)‐((E)‐3‐(2‐phenylhydrazono)butan‐2‐ylidene)amino)oxy)methyl)‐2H‐chromen‐2‐one (5a). The coumarin hydrazone oxime scaffolds were tested in‐vitro against the Mycobacterium tuberculosis H37Rv strain, and Vero cells were used to assess cytotoxicity. Compound 5b was obtained as the hit candidate, exhibiting MIC 0.78 μg/mL, showing more potent anti‐TB activity than Rifamycin and comparable activity to Isoniazid. There was minimal cytotoxicity observed against Vero cells for the most active compounds, indicating a good safety‐profile.In addition, the most diligent compound 5b demonstrated substantial binding interactions at the PDB:4DQU enzyme's active site and also displayed greater C‐score value than that of 4DQU ligand which validates the observed results. [ABSTRACT FROM AUTHOR]

• A series of new coumarino-azetidinones (3a-l) were designed and synthesized. • All the compounds were screened for antitubercular and antimicrobial activity. • Compounds 3e and 3k emerged out as promising antituberculars and antimicrobials. • Compounds 3e and 3k were exhibited comparatively less toxicity. • Excellent molecular docking scores were observed. In the present work, a series of new coumarino-azetidinones (3a-l) were designed, synthesized and evaluated for biological activities. The newly synthesized compounds (3a-l) were fully characterized by several spectroscopic techniques and elemental analyses. The synthesized compounds (3a-l) were screened for their preliminary in-vitro antitubercular and antimicrobial activities. Almost all the coumarino-azetidinones showed promising activity against Mycobacterium tuberculosis (M. tuberculosis) H 37 Rv strain. Conversely, some of the coumarino-azetidinones displayed interesting antimicrobial activities. Moreover, most active compounds were tested for cytotoxicity studies and exhibited low-level cytotoxicity towards Vero cells. Last but not the least, molecular docking results showed excellent interactions with M. tuberculosis InhA-D148G mutant (PDB. 4TZK) and Escherichia coli (E. coli) (PDB. 4JX8). The results of biological evaluation suggest that the coumarino-azetidinones are promising lead compounds for the subsequent investigation in search of new antitubercular and antimicrobial agents. Image, graphical abstract In the present study, a series of new coumarino-azetidinones were synthesized, characterized and evaluated for their preliminary antitubercular, antimicrobial and cytotoxicity activity. [ABSTRACT FROM AUTHOR]

• Novel coumarin-thioether conjugates were synthesised and characterised. • The synthesised compounds are assessed for in vitro anti-TB activity (H 37 Rv strain). • Compound 6b (MIC = 0.39 µg/mL) was twofold more active than Rifampin (0.8 µg/mL). • Compounds 6b and 6f possessed low level of cytotoxicity against Vero cells. • Molecular docking study revealed higher C-score values that supports the findings. In this work, we report a series of 4-(2,6-dimethylphenyl)thio)methyl)-2H-chromen-2-one conjugates as promising leads to treat tuberculosis. Spectroscopic and other analytical methods were used to validate the synthesised compounds. The compounds were assessed for in vitro anti-tubercular activity with the H 37 Rv strain of Mycobacterium tuberculosis. Further, cytotoxicity studies were performed using Vero cells. Most of the synthesised conjugates were effective and displayed notable activity with MIC values in the range 0.39–12.5 µg/mL.The most diligent compound 6b (MIC = 0.39 µg/mL) was twofold more active than standard anti-TB drug Rifampin (0.8 µg/mL) and was comparable to Isoniazid (0.1 µg/mL). Compound 6f also displayed exemplary activity (MIC 0.78 µg/mL). Both compounds 6b and 6f possessed low levels of cytotoxicity, Molecular docking evaluation of the synthesised conjugates and 4DQU ligand demonstrated that the synthesised conjugates had higher C-score values that further supports the obtained results. It indicates compound 6b and 6f are promising lead compounds in search of novel antitubercular drug-like molecules. [Display omitted] [ABSTRACT FROM AUTHOR]

A series of mono and bis -triazole coumarin hybrids 6a–u and 9a–f respectively have been synthesized using 4-(azidomethyl)-2 H -chromen-2-ones 5a–i and aryl propargyl ethers 2a–c/8 employing Click chemistry modified protocol for Azide-Alkyne cycloadditions(CuAAC). Anti-tubercular screening showed moderate activity for mono aryloxy compounds 6a–u with MIC 50–100 μg/mL, whereas the bis compounds 9a–f were more effective with MICs between 0.2 and 12.5 μg/mL. Molecular modeling and 3D-QSAR measurements using CoMFA and Topomer CoMFA further supported the observed results. The bis compound 9b showed excellent activity with MIC value as low as 0.2 μg/mL. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel quinoline and 1,2,4-triazole appended triazole derivatives were conceived. • Microwave synthesis resulted transitory reaction times, exceptional yields and purity. • The reported compounds proclaimed excellent anti-tubercular activity. • All the compounds exhibited exceptional antifungal activity. Quinolin-3-yl-methyl-1,2,3-triazolyl-1,2,4-triazol-3(4 H)-ones 8j-v were synthesized by click chemistry as an ultimate tactic where [3 + 2] cycloaddition of azides with terminal alkynes has been evolved. Herein, we are inclined to divulge the implication and prevalence of CuSO 4 ·5H 2 O and THF/water promoted [3 + 2] cycloaddition reactions. The foremost supremacy of this method are transitory reaction times, facile workup, excellent yields (88–92%) with exorbitant purity and regioselective single product formation both under conventional and microwave method. Docking studies illustrated strong binding interactions with enzyme InhA-D148G (PDB ID: 4DQU) by means of high C-score values. The anti-tubercular and antifungal screening of synthesized compounds proclaimed promising activity. The in vitro and in silico studies imply that these triazoles appended quinolines may acquire the ideal structural prerequisites for auxiliary expansion of novel therapeutic agents. [ABSTRACT FROM AUTHOR]