Synthesis, spectroscopic characterization, and combined DFT/GFN2-xTB study of ethyl 4-[2-(3-hydroxy-4-methoxyphenyl)-4,9-dioxo-2,3,4,9-tetrahydro-1,3-benzoxazepin-3-yl] benzoate
Abstract
A new seven-membered oxygen/nitrogen heterocycle, ethyl 4-[2-(3-hydroxy-4-methoxyphenyl)-4,9-dioxo-2,3,4,9-tetrahydro-1,3-benzoxazepin-3-yl]benzoate (2), was synthesized in two steps from isovanillin and benzocaine. Acid-catalyzed condensation produced azomethine 1, followed by [2+5] cycloaddition with phthalic anhydride to form the seven-membered ring without loss of a small molecule. Both compounds were characterized by FT-IR and ¹H/¹³C NMR spectroscopy. Formation of 2 was confirmed by disappearance of the azomethine band at 1642 cm⁻¹ and appearance of lactone and lactam carbonyl bands at 1709 and 1674 cm⁻¹, respectively. The phenolic O–H bands shifted from 3369 cm⁻¹ in 1 to 3213 and 3113 cm⁻¹ in 2, indicating stronger hydrogen bonding. The azomethine carbon resonance at 162.1 ppm was replaced by lactam and lactone carbonyl signals at 174.9 and 169.2 ppm. Computational studies using B3LYP/6-31G(d), supported by ETKDG, MMFF94, and GFN2-xTB conformational analysis, showed that the heterocycle adopts a twist-boat conformation with a Cremer–Pople puckering amplitude of 0.892 Å. The HOMO–LUMO gap was 4.331 eV, with chemical hardness of 2.166 eV and electrophilicity of 3.241 eV. The molecule exhibits strong electrophilic and nucleophilic characteristics, with an electrostatic potential ranging from −38.0 to +45.3 kcal mol⁻¹.
Keywords:
1,3-Benzoxazepine, Schiff base, [2 5] cycloaddition, Isovanillin, Benzocaine, Density functional theory, Frontier molecular orbitals, Molecular electrostatic potential
References
1. H. Farhid, M. Mahyari, A. Abdolmaleki, Y. Mohammadi, Multicomponent reactions for the synthesis of oxazepines, Topics in Current Chemistry, 2026, 384(3), 23. DOI: 10.1007/s41061-026-00551-1.
2. N. Amri, A. A. Abu-Hashem, Design, synthesis, antimicrobial activity and molecular docking of new 1,2,4-triazepine, 1,3,4,6-oxatriazepine and pyridazino[1,2-a]pyrimidine derivatives, Pharmaceuticals, 2026, 19(1), 83. DOI: 10.3390/ph19010083.
3. D. S. Zinad, A. Mahal, R. K. Mohapatra, A. K. Sarangi, M. R. F. Pratama, Medicinal chemistry of oxazines as promising agents in drug discovery, Chemical Biology & Drug Design, 2020, 95(1), 16–47. DOI: 10.1111/cbdd.13633.
4. M. Luczynski, A. Kudelko, Synthesis and biological activity of 1,3,4-oxadiazoles used in medicine and agriculture, Applied Sciences, 2022, 12(8), 3756. DOI: 10.3390/app12083756.
5. A. A. Dawood, S. R. Mohammed, M. Mahmoud, Synthesis, identification and biological activity of new heterocyclic compounds from reaction of new Schiff bases with phthalic anhydride, Science Journal of University of Zakho, 2020, 8(1), 12–18. DOI: 10.25271/sjuoz.2020.8.1.641.
6. O. A. Nief, H. N. Salman, L. S. Ahamed, Synthesis, characterization, biological activity studies of Schiff bases and 1,3-oxazepine derived from 1,1-bis(4-aminophenyl)-4-phenylcyclohexane, Iraqi Journal of Science, 2017, 58(4B), 1998–2011. DOI: 10.24996/ijs.2017.58.4b.2.
7. K. M. Mohammad, M. R. Ahmed, M. H. Mahmoud, Synthesis and characterization of some new (1,3-oxazepine) derivative from 6-methyl-2-thiouracil and study their biological activity, Tikrit Journal of Pure Science, 2017, 22(2), 67–81. DOI: 10.25130/tjps.v22i2.630.
8. R. B. Nadr, B. S. Abdulrahman, Synthesis and characterization of a new series of [1,3]-oxazepine compounds from heterocyclic Schiff bases, Zanco Journal of Pure and Applied Sciences, 2023, 35(2), art. 21. DOI: 10.21271/zjpas.35.2.21.
9. A. J. Mahrath, S. A. Aowda, S. N. Kamil, Synthesis and spectroscopic studies of some new oxazepine derivatives throughout [2+5] cycloaddition reactions (III), Research on Chemical Intermediates, 2013, 39(8), 3739–3752. DOI: 10.1007/s11164-012-0877-2.
10. B. M. Salih, S. R. Mohammed, M. K. Ali, Synthesis development, spectroscopy characterizations, and molecular docking study of some new bis-1,3-oxazepine and bis-1,3-benzoxazepine derivatives, Oriental Journal of Chemistry, 2025, 41(2), 563–572. DOI: 10.13005/ojc/410227.
11. A. H. Kshash, Synthesis and characterization of tetrachloro-1,3-oxazepine derivatives and evaluation of their biological activities, Acta Chimica Slovenica, 2020, 67(1), 113–118. DOI: 10.17344/acsi.2019.5264.
12. A. K. N. Allamy, S. A. Mejbel, Preparation, characterization and biological activity of some new seven-membered heterocyclic compounds, World Journal of Advanced Research and Reviews, 2022, 15(1), 662–678. DOI: 10.30574/wjarr.2022.15.1.0744.
13. S. J. Khan, S. S. Marufa, M. I. Sultan, A. T. Aurora, J. R. Debnath, S. Easmin, H. Nishino, M. A. Haque, M. M. Rahman, Novel thiophene–thiazole-Schiff base hybrids: design, synthesis, antimicrobial and antioxidant activity with ADMET prediction, molecular docking and dynamics study, RSC Advances, 2025, 15(53), 45690–45706. DOI: 10.1039/D5RA07357J.
14. D. Kumar, N. Aggarwal, H. Kumar, G. Kapoor, A. Deep, S. Bibi, A. Sharma, H. Chopra, R. K. Marwaha, A. Alshammari, M. Alharbi, A. Hayee, 2-Substituted-3-(5-substituted-1,3,4-oxadiazol/thiadiazol-2-yl)thiazolidin-4-one derivatives: synthesis, anticancer, antimicrobial, and antioxidant potential, Pharmaceuticals, 2023, 16(6), 805. DOI: 10.3390/ph16060805.
15. S. K. Singh, N. Mishra, G. Nayak, P. Mehta, Synthesis of Schiff base derivatives of 1,3-oxazepine and evaluation of antioxidant action in vitro, Oriental Journal of Chemistry, 2023, 39(5), 1367–1372. DOI: 10.13005/ojc/390534.
16. A. G. Sager, J. K. Abaies, Z. R. Katoof, Molecular docking, synthesis and evaluation for antioxidant and antibacterial activity of new oxazepane and benzoxazepine derivatives, Baghdad Science Journal, 2024, 21(7), 2289. DOI: 10.21123/bsj.2023.8553.
17. S. A. Hassan, D. M. Aziz, M. N. Abdullah, A. R. Bhat, R. S. Dongre, S. Ahmed, A. K. Rahiman, T. B. Hadda, M. Berredjem, J. Jamalis, Design and synthesis of oxazepine derivatives from sulfonamide Schiff bases as antimicrobial and antioxidant agents with low cytotoxicity and hemolytic prospective, Journal of Molecular Structure, 2023, 1292, 136121. DOI: 10.1016/j.molstruc.2023.136121.
18. R. S. Kumar, S. Naveena, S. Praveen, N. Yogadharshini, Therapeutic aspects of biologically potent vanillin derivatives: a critical review, Journal of Drug Delivery and Therapeutics, 2023, 13(7), 177–189. DOI: 10.22270/jddt.v13i7.6159.
19. B. Demirbağ, M. Yildirim, M. Cimentepe, A. Necip, H. Unver, E. N. Tiftik, Novel vanillin-derived Schiff bases: synthesis, characterization, antibacterial activity, enzyme inhibition, antioxidant activity, anti-inflammatory activity on LPS-induced RAW264.7 macrophage cell line, and in silico studies, Journal of Molecular Structure, 2025, 1338, 142320. DOI: 10.1016/j.molstruc.2025.142320.
20. R. Khan, S. Rashid, S. Khan, Y. A. Almutawif, B. Pari, Synthesis and evaluation of vanillin Schiff bases as potential antimicrobial agents against ESBL-producing bacteria: towards novel interventions in antimicrobial stewardship, Scientific Reports, 2024, 14, 28007. DOI: 10.1038/s41598-024-78302-9.
21. N. Yuldasheva, N. Acikyildiz, M. Akyuz, L. Yabo-Dambagi, T. Aydin, A. Cakir, C. Kazaz, The synthesis of Schiff bases and new secondary amine derivatives of p-vanillin and evaluation of their neuroprotective, antidiabetic, antidepressant and antioxidant potentials, Journal of Molecular Structure, 2022, 1270, 133883. DOI: 10.1016/j.molstruc.2022.133883.
22. R. Karthika, S. Nandhini, S. Suriya, T. Pooventhiran, A. Y. A. Alzahrani, R. Thomas, Synthesis of vanillin derivative Schiff's bases from threonine and valine: structural study and multiscale computational modeling, Biochemical and Biophysical Research Communications, 2025, 781, 152501. DOI: 10.1016/j.bbrc.2025.152501.
23. F. Lemilemu, M. Bitew, T. B. Demissie, R. Eswaramoorthy, M. Endale, Synthesis, antibacterial and antioxidant activities of thiazole-based Schiff base derivatives: a combined experimental and computational study, BMC Chemistry, 2021, 15, 67. DOI: 10.1186/s13065-021-00791-w.
24. N. Elangovan, R. Thomas, S. Sowrirajan, Synthesis of Schiff base (E)-4-((2-hydroxy-3,5-diiodobenzylidene)amino)-N-(thiazol-2-yl)benzenesulfonamide with antimicrobial potential, structural features, experimental biological screening and quantum mechanical studies, Journal of Molecular Structure, 2022, 1250, 131762. DOI: 10.1016/j.molstruc.2021.131762.
25. O. E. Oyeneyin, N. D. Ojo, N. Ipinloju, E. B. Agbaffa, A. V. Emmanuel, Investigation of the corrosion inhibition potentials of some 2-(4-(substituted)arylidene)-1H-indene-1,3-dione derivatives: density functional theory and molecular dynamics simulation, Beni-Suef University Journal of Basic and Applied Sciences, 2022, 11, 132. DOI: 10.1186/s43088-022-00313-0.
26. G. Ramesh, B. Venkatram Reddy, Investigation of barrier potential, structure (monomer and dimer), chemical reactivity, NLO, MEP, and NPA analysis of pyrrole-2-carboxaldehyde using quantum chemical calculations, Polycyclic Aromatic Compounds, 2023, 43(5), 4216–4230. DOI: 10.1080/10406638.2022.2086889.
27. M. Molski, Theoretical study on the radical scavenging activity of gallic acid, Heliyon, 2023, 9(3), e12806. DOI: 10.1016/j.heliyon.2023.e12806.
28. A. A. Hassan, S. Bräse, A. A. Aly, H. N. Tawfeek, Chemistry of substituted thiazinanes and their derivatives, Molecules, 2020, 25(23), 5610. DOI: 10.3390/molecules25235610.
29. Q. Sun, X. Zhang, S. Banerjee, P. Bao, M. Barbry, N. S. Blunt et al., Recent developments in the PySCF program package, Journal of Chemical Physics, 2020, 153(2), 024109. DOI: 10.1063/5.0006074.
30. C. Bannwarth, S. Ehlert, S. Grimme, GFN2-xTB — an accurate and broadly parametrized self-consistent tight-binding quantum chemical method with multipole electrostatics and density-dependent dispersion contributions, Journal of Chemical Theory and Computation, 2019, 15(3), 1652–1671. DOI: 10.1021/acs.jctc.8b01176.
31. L. R. Domingo, M. Ríos-Gutiérrez, P. Pérez, Applications of the conceptual density functional theory indices to organic chemistry reactivity, Molecules, 2016, 21(6), 748. DOI: 10.3390/molecules21060748.
32. M. Ríos-Gutiérrez, A. Saz Sousa, L. R. Domingo, Electrophilicity and nucleophilicity scales at different DFT computational levels, Journal of Physical Organic Chemistry, 2023, 36(7), e4503. DOI: 10.1002/poc.4503.
33. D. Cremer, J. A. Pople, General definition of ring puckering coordinates, Journal of the American Chemical Society, 1975, 97(6), 1354–1358. DOI: 10.1021/ja00839a011.
34. [34] D. Majumdar, A. Chatterjee, M. Feizi-Dehnayebi, N. S. Kiran, B. Tuzun, D. Mishra, 8-Aminoquinoline derived two Schiff base platforms: synthesis, characterization, DFT insights, corrosion inhibitor, molecular docking, and pH-dependent antibacterial study, Heliyon, 2024, 10(15), e35591. DOI: 10.1016/j.heliyon.2024.e35591.
35. M. Khalid, A. Ali, M. F. Ur Rehman, M. Mustaqeem, S. Ali, M. U. Khan, S. Asim, N. Ahmad, M. Saleem, Exploration of noncovalent interactions, chemical reactivity, and nonlinear optical properties of piperidone derivatives: a concise theoretical approach, ACS Omega, 2020, 5(22), 13236–13249. DOI: 10.1021/acsomega.0c01273.
36. M. Khadka, M. Sah, R. Chaudhary, S. K. Sahani, K. Sahani, B. K. Pandey, D. Pandey, Spectroscopic, quantum chemical, and topological calculations of the phenylephrine molecule using density functional theory, Scientific Reports, 2025, 15, 208. DOI: 10.1038/s41598-024-81633-2.
37. M. El-Naggar, H. R. M. Rashdan, A. H. Abdelmonsef, Cyclization of chalcone derivatives: design, synthesis, in silico docking study, and biological evaluation of new quinazolin-2,4-diones incorporating five-, six-, and seven-membered ring moieties as potent antibacterial inhibitors, ACS Omega, 2023, 8(30), 27216–27230. DOI: 10.1021/acsomega.3c02478.
2. N. Amri, A. A. Abu-Hashem, Design, synthesis, antimicrobial activity and molecular docking of new 1,2,4-triazepine, 1,3,4,6-oxatriazepine and pyridazino[1,2-a]pyrimidine derivatives, Pharmaceuticals, 2026, 19(1), 83. DOI: 10.3390/ph19010083.
3. D. S. Zinad, A. Mahal, R. K. Mohapatra, A. K. Sarangi, M. R. F. Pratama, Medicinal chemistry of oxazines as promising agents in drug discovery, Chemical Biology & Drug Design, 2020, 95(1), 16–47. DOI: 10.1111/cbdd.13633.
4. M. Luczynski, A. Kudelko, Synthesis and biological activity of 1,3,4-oxadiazoles used in medicine and agriculture, Applied Sciences, 2022, 12(8), 3756. DOI: 10.3390/app12083756.
5. A. A. Dawood, S. R. Mohammed, M. Mahmoud, Synthesis, identification and biological activity of new heterocyclic compounds from reaction of new Schiff bases with phthalic anhydride, Science Journal of University of Zakho, 2020, 8(1), 12–18. DOI: 10.25271/sjuoz.2020.8.1.641.
6. O. A. Nief, H. N. Salman, L. S. Ahamed, Synthesis, characterization, biological activity studies of Schiff bases and 1,3-oxazepine derived from 1,1-bis(4-aminophenyl)-4-phenylcyclohexane, Iraqi Journal of Science, 2017, 58(4B), 1998–2011. DOI: 10.24996/ijs.2017.58.4b.2.
7. K. M. Mohammad, M. R. Ahmed, M. H. Mahmoud, Synthesis and characterization of some new (1,3-oxazepine) derivative from 6-methyl-2-thiouracil and study their biological activity, Tikrit Journal of Pure Science, 2017, 22(2), 67–81. DOI: 10.25130/tjps.v22i2.630.
8. R. B. Nadr, B. S. Abdulrahman, Synthesis and characterization of a new series of [1,3]-oxazepine compounds from heterocyclic Schiff bases, Zanco Journal of Pure and Applied Sciences, 2023, 35(2), art. 21. DOI: 10.21271/zjpas.35.2.21.
9. A. J. Mahrath, S. A. Aowda, S. N. Kamil, Synthesis and spectroscopic studies of some new oxazepine derivatives throughout [2+5] cycloaddition reactions (III), Research on Chemical Intermediates, 2013, 39(8), 3739–3752. DOI: 10.1007/s11164-012-0877-2.
10. B. M. Salih, S. R. Mohammed, M. K. Ali, Synthesis development, spectroscopy characterizations, and molecular docking study of some new bis-1,3-oxazepine and bis-1,3-benzoxazepine derivatives, Oriental Journal of Chemistry, 2025, 41(2), 563–572. DOI: 10.13005/ojc/410227.
11. A. H. Kshash, Synthesis and characterization of tetrachloro-1,3-oxazepine derivatives and evaluation of their biological activities, Acta Chimica Slovenica, 2020, 67(1), 113–118. DOI: 10.17344/acsi.2019.5264.
12. A. K. N. Allamy, S. A. Mejbel, Preparation, characterization and biological activity of some new seven-membered heterocyclic compounds, World Journal of Advanced Research and Reviews, 2022, 15(1), 662–678. DOI: 10.30574/wjarr.2022.15.1.0744.
13. S. J. Khan, S. S. Marufa, M. I. Sultan, A. T. Aurora, J. R. Debnath, S. Easmin, H. Nishino, M. A. Haque, M. M. Rahman, Novel thiophene–thiazole-Schiff base hybrids: design, synthesis, antimicrobial and antioxidant activity with ADMET prediction, molecular docking and dynamics study, RSC Advances, 2025, 15(53), 45690–45706. DOI: 10.1039/D5RA07357J.
14. D. Kumar, N. Aggarwal, H. Kumar, G. Kapoor, A. Deep, S. Bibi, A. Sharma, H. Chopra, R. K. Marwaha, A. Alshammari, M. Alharbi, A. Hayee, 2-Substituted-3-(5-substituted-1,3,4-oxadiazol/thiadiazol-2-yl)thiazolidin-4-one derivatives: synthesis, anticancer, antimicrobial, and antioxidant potential, Pharmaceuticals, 2023, 16(6), 805. DOI: 10.3390/ph16060805.
15. S. K. Singh, N. Mishra, G. Nayak, P. Mehta, Synthesis of Schiff base derivatives of 1,3-oxazepine and evaluation of antioxidant action in vitro, Oriental Journal of Chemistry, 2023, 39(5), 1367–1372. DOI: 10.13005/ojc/390534.
16. A. G. Sager, J. K. Abaies, Z. R. Katoof, Molecular docking, synthesis and evaluation for antioxidant and antibacterial activity of new oxazepane and benzoxazepine derivatives, Baghdad Science Journal, 2024, 21(7), 2289. DOI: 10.21123/bsj.2023.8553.
17. S. A. Hassan, D. M. Aziz, M. N. Abdullah, A. R. Bhat, R. S. Dongre, S. Ahmed, A. K. Rahiman, T. B. Hadda, M. Berredjem, J. Jamalis, Design and synthesis of oxazepine derivatives from sulfonamide Schiff bases as antimicrobial and antioxidant agents with low cytotoxicity and hemolytic prospective, Journal of Molecular Structure, 2023, 1292, 136121. DOI: 10.1016/j.molstruc.2023.136121.
18. R. S. Kumar, S. Naveena, S. Praveen, N. Yogadharshini, Therapeutic aspects of biologically potent vanillin derivatives: a critical review, Journal of Drug Delivery and Therapeutics, 2023, 13(7), 177–189. DOI: 10.22270/jddt.v13i7.6159.
19. B. Demirbağ, M. Yildirim, M. Cimentepe, A. Necip, H. Unver, E. N. Tiftik, Novel vanillin-derived Schiff bases: synthesis, characterization, antibacterial activity, enzyme inhibition, antioxidant activity, anti-inflammatory activity on LPS-induced RAW264.7 macrophage cell line, and in silico studies, Journal of Molecular Structure, 2025, 1338, 142320. DOI: 10.1016/j.molstruc.2025.142320.
20. R. Khan, S. Rashid, S. Khan, Y. A. Almutawif, B. Pari, Synthesis and evaluation of vanillin Schiff bases as potential antimicrobial agents against ESBL-producing bacteria: towards novel interventions in antimicrobial stewardship, Scientific Reports, 2024, 14, 28007. DOI: 10.1038/s41598-024-78302-9.
21. N. Yuldasheva, N. Acikyildiz, M. Akyuz, L. Yabo-Dambagi, T. Aydin, A. Cakir, C. Kazaz, The synthesis of Schiff bases and new secondary amine derivatives of p-vanillin and evaluation of their neuroprotective, antidiabetic, antidepressant and antioxidant potentials, Journal of Molecular Structure, 2022, 1270, 133883. DOI: 10.1016/j.molstruc.2022.133883.
22. R. Karthika, S. Nandhini, S. Suriya, T. Pooventhiran, A. Y. A. Alzahrani, R. Thomas, Synthesis of vanillin derivative Schiff's bases from threonine and valine: structural study and multiscale computational modeling, Biochemical and Biophysical Research Communications, 2025, 781, 152501. DOI: 10.1016/j.bbrc.2025.152501.
23. F. Lemilemu, M. Bitew, T. B. Demissie, R. Eswaramoorthy, M. Endale, Synthesis, antibacterial and antioxidant activities of thiazole-based Schiff base derivatives: a combined experimental and computational study, BMC Chemistry, 2021, 15, 67. DOI: 10.1186/s13065-021-00791-w.
24. N. Elangovan, R. Thomas, S. Sowrirajan, Synthesis of Schiff base (E)-4-((2-hydroxy-3,5-diiodobenzylidene)amino)-N-(thiazol-2-yl)benzenesulfonamide with antimicrobial potential, structural features, experimental biological screening and quantum mechanical studies, Journal of Molecular Structure, 2022, 1250, 131762. DOI: 10.1016/j.molstruc.2021.131762.
25. O. E. Oyeneyin, N. D. Ojo, N. Ipinloju, E. B. Agbaffa, A. V. Emmanuel, Investigation of the corrosion inhibition potentials of some 2-(4-(substituted)arylidene)-1H-indene-1,3-dione derivatives: density functional theory and molecular dynamics simulation, Beni-Suef University Journal of Basic and Applied Sciences, 2022, 11, 132. DOI: 10.1186/s43088-022-00313-0.
26. G. Ramesh, B. Venkatram Reddy, Investigation of barrier potential, structure (monomer and dimer), chemical reactivity, NLO, MEP, and NPA analysis of pyrrole-2-carboxaldehyde using quantum chemical calculations, Polycyclic Aromatic Compounds, 2023, 43(5), 4216–4230. DOI: 10.1080/10406638.2022.2086889.
27. M. Molski, Theoretical study on the radical scavenging activity of gallic acid, Heliyon, 2023, 9(3), e12806. DOI: 10.1016/j.heliyon.2023.e12806.
28. A. A. Hassan, S. Bräse, A. A. Aly, H. N. Tawfeek, Chemistry of substituted thiazinanes and their derivatives, Molecules, 2020, 25(23), 5610. DOI: 10.3390/molecules25235610.
29. Q. Sun, X. Zhang, S. Banerjee, P. Bao, M. Barbry, N. S. Blunt et al., Recent developments in the PySCF program package, Journal of Chemical Physics, 2020, 153(2), 024109. DOI: 10.1063/5.0006074.
30. C. Bannwarth, S. Ehlert, S. Grimme, GFN2-xTB — an accurate and broadly parametrized self-consistent tight-binding quantum chemical method with multipole electrostatics and density-dependent dispersion contributions, Journal of Chemical Theory and Computation, 2019, 15(3), 1652–1671. DOI: 10.1021/acs.jctc.8b01176.
31. L. R. Domingo, M. Ríos-Gutiérrez, P. Pérez, Applications of the conceptual density functional theory indices to organic chemistry reactivity, Molecules, 2016, 21(6), 748. DOI: 10.3390/molecules21060748.
32. M. Ríos-Gutiérrez, A. Saz Sousa, L. R. Domingo, Electrophilicity and nucleophilicity scales at different DFT computational levels, Journal of Physical Organic Chemistry, 2023, 36(7), e4503. DOI: 10.1002/poc.4503.
33. D. Cremer, J. A. Pople, General definition of ring puckering coordinates, Journal of the American Chemical Society, 1975, 97(6), 1354–1358. DOI: 10.1021/ja00839a011.
34. [34] D. Majumdar, A. Chatterjee, M. Feizi-Dehnayebi, N. S. Kiran, B. Tuzun, D. Mishra, 8-Aminoquinoline derived two Schiff base platforms: synthesis, characterization, DFT insights, corrosion inhibitor, molecular docking, and pH-dependent antibacterial study, Heliyon, 2024, 10(15), e35591. DOI: 10.1016/j.heliyon.2024.e35591.
35. M. Khalid, A. Ali, M. F. Ur Rehman, M. Mustaqeem, S. Ali, M. U. Khan, S. Asim, N. Ahmad, M. Saleem, Exploration of noncovalent interactions, chemical reactivity, and nonlinear optical properties of piperidone derivatives: a concise theoretical approach, ACS Omega, 2020, 5(22), 13236–13249. DOI: 10.1021/acsomega.0c01273.
36. M. Khadka, M. Sah, R. Chaudhary, S. K. Sahani, K. Sahani, B. K. Pandey, D. Pandey, Spectroscopic, quantum chemical, and topological calculations of the phenylephrine molecule using density functional theory, Scientific Reports, 2025, 15, 208. DOI: 10.1038/s41598-024-81633-2.
37. M. El-Naggar, H. R. M. Rashdan, A. H. Abdelmonsef, Cyclization of chalcone derivatives: design, synthesis, in silico docking study, and biological evaluation of new quinazolin-2,4-diones incorporating five-, six-, and seven-membered ring moieties as potent antibacterial inhibitors, ACS Omega, 2023, 8(30), 27216–27230. DOI: 10.1021/acsomega.3c02478.
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Abdullah, R. N. (2026). Synthesis, spectroscopic characterization, and combined DFT/GFN2-xTB study of ethyl 4-[2-(3-hydroxy-4-methoxyphenyl)-4,9-dioxo-2,3,4,9-tetrahydro-1,3-benzoxazepin-3-yl] benzoate. Journal of Integral Sciences, 9(2), 30-45. https://doi.org/10.37022/jis.v9i2.149
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