Faculty Publications
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Item Discovery of 1,2,3-triazole incorporated indole-piperazines as potent antitubercular agents: Design, synthesis, in vitro biological evaluation, molecular docking and ADME studies(Elsevier Ltd, 2024) Reddyrajula, R.; Etikyala, U.; Vijjulatha, V.; Udayakumar, U.In this report, a library consisting of three sets of indole-piperazine derivatives was designed through the molecular hybridization approach. In total, fifty new hybrid compounds (T1-T50) were synthesized and screened for antitubercular activity against Mycobacterium tuberculosis H37Rv strain (ATCC-27294). Five (T36, T43, T44, T48 and T49) among fifty compounds exhibited significant inhibitory potency with the MIC of 1.6 µg/mL, which is twofold more potent than the standard first-line TB drug Pyrazinamide and equipotent with Isoniazid. N-1,2,3-triazolyl indole-piperazine derivatives displayed improved inhibition activity as compared to the simple and N-benzyl indole-piperazine derivatives. In addition, the observed activity profile of indole-piperazines was similar to standard anti-TB drugs (isoniazid and pyrazinamide) against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa strains, demonstrating the compounds’ selectivity towards the Mycobacterium tuberculosis H37Rv strain. All the active anti-TB compounds are proved to be non-toxic (with IC50 > 300 μg/mL) as verified through the toxicity evaluation against VERO cell lines. Additionally, molecular docking studies against two target enzymes (Inh A and CYP121) were performed to validate the activity profile of indole-piperazine derivatives. Further, in silico-ADME prediction and pharmacokinetic parameters indicated that these compounds have good oral bioavailability. © 2023 Elsevier LtdItem Design, synthesis and molecular docking of 5-fluoro indole derivatives as inhibitors of PI3K/Akt signalling pathway in cervical cancer(Elsevier B.V., 2024) Etikyala, U.; Reddyrajula, R.; Pasha, A.; Udayakumar, U.; Pawar, S.C.; Vijjulatha, V.The PI3K/Akt signalling pathway promotes variety of cellular processes and the inhibition of PI3K/Akt signalling pathway could lead to decrease in tumour growth effectively in cancer cells. AD412, an indole derivative, is a potent immunosuppressive agent which also reported as an anticancer agent through significant inhibition of PI3K/Akt signalling pathway. In this current work, we designed and synthesized the two diverse lead series of 5-fluoro indole derivatives (6a-l and 11a-l) by specific structural modifications of AD412. In total, 24 new derivatives were evaluated for their antiproliferative activity against two cervical cancer cell lines (HeLa and SiHa) and a normal cell line (HEK 293). Among them, 6e exhibited excellent antiproliferative activity against HeLa and SiHa cells with IC50 values of 9.366 and 8.475 µM respectively, as well displayed a low toxicity profile. Further, 6e inhibited the migration and invasion of HeLa cells in a dose-dependent manner by affecting the synthesis of DNA. Moreover, the Western blot analysis revealed that 6e could inhibit cervical cancer progression by downregulating the PI3K-p85 and phosphorylation of Akt in Hela cells. In vitro mechanism studies demonstrated that 6e could significantly increase apoptosis in HeLa cells by upregulating the expression of proapoptosis related protein Bax. The binding mechanism and the activity profile of 5-fluoro indole derivatives were validated by employing molecular docking studies against the active sites of Akt and PI3K enzymes. In addition, in silico ADME and pharmacokinetic parameters prediction of compound 6e resulted in good oral bioavailability. Therefore, compound 6e could be a lead compound for further development of PI3K/Akt inhibitors and anticancer agents. © 2024Item N-Acyl phenothiazines as mycobacterial ATP synthase inhibitors: Rational design, synthesis and in vitro evaluation against drug sensitive, RR and MDR-TB(Academic Press Inc., 2024) Reddyrajula, R.; Perveen, S.; Negi, A.; Etikyala, U.; Vijjulatha, V.; Sharma, R.; Udayakumar, D.The mycobacterial F-ATP synthase is responsible for the optimal growth, metabolism and viability of Mycobacteria, establishing it as a validated target for the development of anti-TB therapeutics. Herein, we report the discovery of an N-acyl phenothiazine derivative, termed PT6, targeting the mycobacterial F-ATP synthase. PT6 is bactericidal and active against the drug sensitive, Rifampicin-resistant as well as Multidrug-resistant tuberculosis strains. Compound PT6 showed noteworthy inhibition of F-ATP synthesis, exhibiting an IC50 of 0.788 µM in M. smegmatis IMVs and was observed that it could deplete intracellular ATP levels, exhibiting an IC50 of 30 µM. PT6 displayed a high selectivity towards mycobacterial ATP synthase compared to mitochondrial ATP synthase. Compound PT6 showed a minor synergistic effect in combination with Rifampicin and Isoniazid. PT6 demonstrated null cytotoxicity as confirmed by assessing its toxicity against VERO cell lines. Further, the binding mechanism and the activity profile of PT6 were validated by employing in silico techniques such as molecular docking, Prime MM/GBSA, DFT and ADMET analysis. These results suggest that PT6 presents an attractive lead for the discovery of a novel class of mycobacterial F-ATP synthase inhibitors. © 2024 Elsevier Inc.Item Ionic liquid promoted facile one-pot synthesis of phenothiazine-thiazolidin-4-ones as potent antitubercular agents via mycobacterial ATP synthase inhibition(Elsevier B.V., 2025) Reddyrajula, R.; Etikyala, U.; Mahapathra, H.C.; Udaybhan, R.A.; Vijjulatha, V.; Udayakumar, U.The mycobacterial ATP synthase is responsible for the optimal growth, metabolism and viability of mycobacteria, establishing it as a validated target for the development of anti-TB therapeutics. Herein, we report the facile and efficient one-pot three component synthesis of 2-(10H-phenothiazin-3-yl)-3-substituted thiazolidin-4-one derivatives by using ionic liquid, 1?butyl?3-methylimidazolium bromide [Bmim]Br and their inhibitory potency against mycobacterium tuberculosis H37Rv strain (ATCC-27,294). Compound T27 exhibited the highest inhibition activity with an MIC of 0.78 ?g/mL, which is twofold and fourfold superior (in terms of the MIC values) to the standard first-line TB drugs isoniazid (MIC: 1.56 ?g/mL) and pyrazinamide (MIC: 3.12 ?g/mL) respectively. Two other compounds (T25 and T30) are equipotent as the isoniazid. The SAR studies revealed that insertion of 1,2,3-traizole and thiozolidine-2-one rings enhance the anti-TB activity in most of the tested compounds. Also, compound T27 was screened for mycobacterial ATP synthase inhibition activity and it exhibited an IC50 of 0.735 µM in M. smegmatis IMVs. Further, toxicity evaluation against VERO cell lines confirmed null cytotoxicity (selectivity index > 70) of the potent analogues. The title compounds are highly specific towards to the M. tb strain, i.e., most of the compounds exhibited moderate inhibitory potency against the tested bacterial strains (MIC ? 6.25 ?g/mL). In addition, molecular docking was employed against the active site of the ATP synthase enzyme to validate the binding mechanism and in vitro activity profile of the phenothiazine derivatives. Furthermore, in silico ADME and pharmacokinetic parameters’ prediction indicated good oral bioavailability. © 2024 Elsevier B.V.Item An in silico approach to identify novel and potential Akt1 (protein kinase B-alpha) inhibitors as anticancer drugs(Springer Nature, 2025) Etikyala, U.; Reddyrajula, R.; Vani, T.; Kuchana, V.; Udayakumar, U.; Vijjulatha, V.Akt1 (protein kinase B) has become a major focus of attention due to its significant functionality in a variety of cellular processes and the inhibition of Akt1 could lead to a decrease in tumour growth effectively in cancer cells. In the present work, we discovered a set of novel Akt1 inhibitors by using multiple computational techniques, i.e. pharmacophore-based virtual screening, molecular docking, binding free energy calculations, and ADME properties. A five-point pharmacophore hypothesis was implemented and validated with AADRR38. The obtained R2 and Q2 values are in the acceptable region with the values of 0.90 and 0.64, respectively. The generated pharmacophore model was employed for virtual screening to find out the potential Akt1 inhibitors. Further, the selected hits were subjected to molecular docking, binding free energy analysis, and refined using ADME properties. Also, we designed a series of 6-methoxybenzo[b]oxazole analogues by comprising the structural characteristics of the hits acquired from the database. Molecules D1–D10 were found to have strong binding interactions and higher binding free energy values. In addition, Molecular dynamic simulation was performed to understand the conformational changes of protein–ligand complex. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.Item Exploring Indole-1,3,4-Thiadiazole Schiff Base Derivatives as Anticancer Agents: Design, Synthesis, In Vitro and In Silico Evaluation(John Wiley and Sons Ltd, 2025) Etikyala, U.; Reddyrajula, R.; Udayakumar, U.; Kokku, P.; Vijjulatha, V.Cancer remains a major global health challenge, with resistance to existing therapeutic regimens underscoring the development of novel agents with improved efficacy and reduced toxicity. The indole and 1,3,4-thiadiazole scaffolds are distinguished for their broad-spectrum bioactivities, including anticancer properties. In this study, the synthesis and biological evaluation of a new series of indole-1,3,4-thiadiazole Schiff bases (U1-U31) designed to enhance anticancer efficacy is explored. In vitro evaluation demonstrates potent and selective cytotoxicity of several compounds, particularly U19 and U24, against multiple cancer cell lines, with minimal toxicity to normal cells. Molecular docking and density functional theory studies demonstrate that these hybrid compounds effectively occupy the ATP-binding sites of Pi3K and Akt proteins, exhibiting notable binding interactions comparable to the respective standard inhibitors. In addition, molecular dynamics simulation is performed to understand the conformational changes of the protein–ligand complex. Overall, the findings indicate that these novel indole-1,3,4-thiadiazole derivatives have selective inhibitory potency, making them promising leads for further anticancer drug development. © 2025 Wiley-VCH GmbH.