Chemical Research in Chinese Universities ›› 2026, Vol. 42 ›› Issue (3): 983-991.doi: 10.1007/s40242-026-6048-6

• Research Articles • Previous Articles     Next Articles

Novel Approach to Synthesis of Diaryl Tacrine Derivatives and Evaluation of Their Inhibitory Effects on Cholinesterase Enzymes

TOPAL Fevzi1, ÖKTEN Salih2, ALBAYRAK MISIR Büşra3,5, KOÇYİĞİT Ümit Muhammet4, DERİN Yavuz5, ENİSOĞLU ATALAY Vildan6, TUTAR Ahmet5, TOPAL Meryem7   

  1. 1. Department of Nutrition and Dietetic, Faculty of Health Sciences, Gümüşhane University, Gümüşhane, 29100, Türkiye;
    2. Department of Maths and Science Education, Faculty of Education, Kırıkkale University, Yahşihan, Kırıkkale, 71000, Türkiye;
    3. Department of Chemistry, Faculty of Science, Kahramanmaraş Sütçü İmam University, Onikişubat, Kahramanmaraş, 46000, Türkiye;
    4. Department of Biochemistry, Faculty of Pharmacy, Sivas Cumhuriyet University, Sivas, 58010, Türkiye;
    5. Department of Chemistry, Faculty of Science, Sakarya University, Serdivan, Sakarya, 54000, Türkiye;
    6. Institute of Informatics, Istanbul Technical University, İstanbul, 34467, Türkiye;
    7. Department of Medical Services and Techniques, Vocational School of Health Services, Gümüşhane University, Gümüşhane, 29100, Türkiye
  • Received:2026-02-19 Accepted:2026-04-03 Published:2026-06-02
  • Contact: TOPAL Fevzi,E-mail:ftopal@gumushane.edu.tr;ÖKTEN Salih,E-mail:sokten@gmail.com E-mail:ftopal@gumushane.edu.tr;sokten@gmail.com
  • Supported by:
    This work was supported by the Project of the Turkish Health Institutes (TUSEB A-Project No. 24138).

Abstract: The development of effective acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors remains a crucial objective in the treatment of neurodegenerative diseases, including Alzheimer’s disease (AD). In this study, a novel synthetic approach was established to prepare a series of diaryl-substituted tacrine derivatives. Initially, brominated aminobenzonitrile was subjected to Suzuki-Miyaura cross-coupling reactions with various aryl boronic acids to yielding diaryl-substituted aminobenzonitriles at yields of 60%–72%. These intermediates were then cyclized with cyclohexanone and cycloheptanone under Friedländer conditions using BF3·OEt2 as a catalyst, affording six- and seven-membered diaryl tacrine analogues in yields of 52%–68%. All synthesized compounds were characterized by NMR, IR, and elemental analysis. The inhibitory activities of these compounds (7–16) against AChE and BChE were evaluated, and several analogs demonstrated potent dual-enzyme inhibition at nanomolar concentrations. Notably, compounds 8 and 13 exhibited half maximal inhibitory concentration (IC50) values of 6.848 and 8.545 nmol/L for BChE, respectively, indicating strong potential as selective cholinesterase inhibitors. The structure-activity relationship (SAR) analysis revealed the influence of aryl substituents on the potency and selectivity of enzyme inhibition. Compared to previously reported tacrine derivatives, the newly synthesized analogs exhibited superior inhibitory profiles, indicating their potential as lead compounds for further development in AD therapeutics.

Key words: Acetylcholinesterase (AChE), Aminobenzonitrile, Aryl, Butylcholinesterase (BChE), Structure-activity relationship (SAR), Tacrine