Abstract
Objectives: 1,2-thiazine and pyridine heterocycles drew much attention due to their biological
activities, including antioxidant activity. Based on fragment-based drug design, novel pyrido[1,2]thiazines
9a-c, thiazolidinopyrido[1,2], thiazines 10a-c and azetidinopyrido[1,2]thiazines 11a-c were designed and
prepared.
Methods: These novel derivatives 9a-c, 10a-c and 11a-c were subjected to screening for their antioxidant
activity via various assays as DPPH radical scavenging potential, reducing power assay and metal chelating
potential.
Results: All the assayed derivatives exhibited excellent antioxidant potential and the tested compounds
9a, 9b, 10a, 10b, 11a and 11b exhibited higher DPPH scavenging potential (EC50 = 32.7, 53, 36.1, 60,
40.6 and 67 μM, respectively) than ascorbic acid (EC50 = 86.58 μM). While targets 9a, 10a and 11a (RP50
= 52.19, 59.16 and 52.25 μM, respectively) exhibited better reducing power than the ascorbic acid (RP50
= 84.66 μM). The computational analysis had been utilized to prophesy the bioactivity and molecular
properties of the target compounds.
Conclusion: To predict the binding manner of the novel derivatives as antioxidants, in-silico docking
study was performed on all the newly prepared compounds inside superoxide dismutase (SOD) and catalase
(CAT) active site. The most active antioxidant candidate 9a (EC50 = 32.7 μM, RP50 = 52.19 μM)
displayed excellent binding with Lys134 amino acid residing at Cu-Zn loop of SOD with binding energy
score = -7.54 Kcal/mol, thereby increasing SOD activity and decreasing reactive oxygen species.
Keywords:
2, 2-diphenyl-1-picrylhydrazyl, reducing power, reactive oxygen species, antioxidant, docking study, synthesis.
Graphical Abstract
[5]
Ortiz, G.G.; Pacheco-Moisés, F.P.; Mireles-Ramírez, M.A.; Flores-Alvarado, L.J.; González-Usigli, H.; Sánchez-López, A.L. Oxidative stress and Parkinson’s disease: Effects on environmental toxicology. In: Free Radicals and Diseases; Intech, 2016, pp. 183-209.
[21]
Malinka, W.; Gamian, A.; Berenika, S. Synthesis and studies on antibacterial activity of pyrido [3, 2-e]-1, 2-thiazines and related deriva-tives. Tuberculosis, 2008, 37, 6.
[27]
Elkanzi, N.A.; Bakr, R.B.; Ghoneim, A.A. Design, synthesis, molecular modeling study, and antimicrobial activity of some novel pyrano [2, 3-b] pyridine and pyrrolo [2, 3-b] pyrano [2.3-d] pyridine derivatives. J. Heterocycl. Chem., 2019, 56, 406-416.
[36]
Elkanzi, N.A.; Hrichi, H.; Bakr, R.B.; Hendawy, O.; Alruwaili, M.M.; Alruwaili, E.D. Synthesis, in vitro evaluation and molecular docking of new pyrazole derivatives bearing 1, 5, 10, 10a-tetrahydrobenzo [g] quinoline-3-carbonitrile moiety as potent antibacterial agents. J. Iran. Chem. Soc., 2021, 18, 977-991.
[41]
Abdelall, E.; Bakr, R.; Abdel-Hamid, M.; Kandeel, M. Enhancement to synthesize, design and dock of novel EGFR inhibitors containing pyrazolo [3, 4-d] pyrimidine cores of expected anticancer activity. OCAIJ, 2014, 10, 470-483.
[45]
Abdellatif, K.R.; Bakr, R.B. Pyrimidine and fused pyrimidine derivatives as promising protein kinase inhibitors for cancer treatment. Med. Chem. Res., 2021, 30, 31-49.
[58]
Malinka, W.; Sieklucka-Dziuba, M.; Rajtar-Cynke, G.; Borowicz, K.; Kleinrok, Z. Studies on synthesis and biological properties of
pyrazolo [4, 3-c]-pyrido [3, 2-e]-1, 2-thiazine-5, 5-dioxide bearing
4-substituted-1-piperazinylpropyl moiety. Farmaco (Societa chimica
italiana: 1989), 1994, 49, 783-792.
[63]
Drăgan, M.; Stan, C.D.; Pânzariu, A.; Profire, L. Assessment of in vitro antioxidant and antiinflamatory activities of new azetidin-2-ones derivatives of ferulic acid. Farmacia, 2016, 64, 717-721.