Antitubercular activity assessment of fluorinated chalcones, 2-aminopyridine-3-carbonitrile and 2-amino-4H-pyran-3-carbonitrile derivatives: In vitro, molecular docking and in-silico drug likeliness studies

A series of newer previously synthesized fluorinated chalcones and their 2-amino-pyridine-3-carbonitrile and 2-amino-4H-pyran-3-carbonitrile derivatives were screened for their in vitro antitubercular activity and in silico methods. Compound 40 (MIC~ 8 μM) was the most potent among all 60 compounds, whose potency is comparable with broad spectrum antibiotics like ciprofloxacin and streptomycin and three times more potent than pyrazinamide. Additionally, compound 40 was also less selective and hence non-toxic towards the human live cell lines-LO2 in its MTT assay. Compounds 30, 27, 50, 41, 51, and 60 have exhibited streptomycin like activity (MIC~16–18 μM). Fluorinated chalcones, pyridine and pyran derivatives were found to occupy prime position in thymidylate kinase enzymatic pockets in molecular docking studies. The molecule 40 being most potent had shown a binding energy of -9.67 Kcal/mol, while docking against thymidylate kinase, which was compared with its in vitro MIC value (~8 μM). These findings suggest that 2-aminopyridine-3-carbonitrile and 2-amino-4H-pyran-3-carbonitrile derivatives are prospective lead molecules for the development of novel antitubercular drugs.

Synthesis, Biological and Computational Evaluation of Novel 2,3-dihydro-2-aryl-4-(4- isobutylphenyl)-1,5-benzothiazepine Derivatives as Anticancer and Anti-EGFR Tyrosine Kinase Agents

BACKGROUND

Despite the availability of a variety of chemotherapeutic agents, cancer is still one of the leading causes of death worldwide because of the problems with existing chemotherapeutic agents like objectionable side effects, lack of selectivity, and resistance. Hence, there is an urgent need for the development of novel anticancer agents with high usefulness, fewer side effects, devoid of resistance and superior selectivity.

OBJECTIVE

The objective of this study is to synthesize a series of novel 1,5-benzothiazepine derivatives and evaluate their anticancer activity employing biological and computational methods.

METHODS

Twenty new benzothiazepines (BT1-BT20) were prepared by condensing different 1-(4- isobutylphenyl)ethanone chalcones with 2-amiothiophenol and evaluated for their anticancer activity by MTT assay against three cell lines including HT-29 (colon cancer), MCF-7 (breast cancer) and DU-145 (prostate cancer). These compounds were also tested for their inhibitory action against EGFR (Epidermal Growth Factor Receptor) tyrosine kinase enzyme by taking into account of their excellent action against colon and breast cancer cell lines. Further, the structural features responsible for the activity were identified by Pharmacophorebased modelling using Schrodinger's PHASETM software.

RESULTS

Among the 20 benzothiazepine derivatives, three compounds viz., BT18, BT19 and BT20 exhibited promising activity against the cell lines tested and the activity of BT20 was more than the standard methotrexate. Again the above three compounds showed excellent inhibitory activity with the percentage inhibition of 64.5, 57.3 and 55.8 respectively against EGFR (Epidermal Growth Factor Receptor) tyrosine kinase. PHASE identified a five-point AHHRR model for the proposed activity and the computational studies provided insights into the structural requirements for the anticancer activity and the results were consistent with the observed in vitro activity data.

CONCLUSION

These novel benzothiazepines will be useful as lead molecules for the further development of new cancer therapies against colon and breast cancers.

Antimicrobial, Antioxidant, and Anticancer Activities of Some Novel Isoxazole Ring Containing Chalcone and Dihydropyrazole Derivatives

Our previous work identified isoxazole-based chalcones and their dihydropyrazole derivatives as two important five-membered heterocycles having antitubercular activity. Hence, in the present study, we biologically evaluated 30 compounds, including 15 isoxazole ring-containing chalcones (17-31) and 15 dihydropyrazoles (32-46) derived from these chalcones for their antimicrobial, antioxidant, and anticancer activities. Chalcones exhibited superior antibacterial and antioxidant activities compared to dihydropyrazoles. Among the chalcones, compound 28 showed potent antibacterial (MIC = 1 µg/mL) and antioxidant activities (IC₅₀ = 5 ± 1 µg/mL). Dihydropyrazoles, on the contrary, demonstrated remarkable antifungal and anticancer activities. Compound 46 (IC₅₀ = 2 ± 1 µg/mL) showed excellent antifungal activity whereas two other dihydropyrazoles 45 (IC₅₀ = 2 ± 1 µg/mL) and 39 (IC₅₀ = 4 ± 1 µg/mL) exhibited potential anticancer activity. The compounds were also tested for their toxicity on normal human cell lines (LO2) and were found to be nontoxic. The active compounds that have emerged out of this study are potential lead molecules for the development of novel drugs against infectious diseases, oxidative stress, and cancer.