DESIGN, SYNTHESIS AND BIOLOGICAL EVALUATION OF NEW MULTI-TARGET 4-METHYLTHIAZOLE DERIVATIVES FOR TREATMENT OF ALZHEIMER’S DISEASE

Öz

Objective: In this study, eight new 4-methylthiazole derivatives were designed and synthesized with the aim of exhibiting multi-target effects in the treatment of Alzheimer's disease. Their cholinesterase inhibitor activities, antioxidant properties, and metal chelator effects were tested in vitro.

Material and Method: The title compounds were obtained using 4-methylthiazole-2-amine as the starting material. According to method A, intermediate 1 was synthesized by reacting the starting material with 3-chloropropionyl chloride. Subsequently, the title compounds (2a-f) were obtained via substitution reactions with suitable amine derivatives. The title compounds that could not be obtained by method A were prepared from the reaction of starting material with appropriate propanoic acid derivatives using method B. Structural analysis of the synthesized and purified final compounds were elucidated using ¹H-NMR, ¹³C-NMR, and HRMS methods. The cholinesterase inhibitor effects of all synthesized compounds were determined using the modified Ellman method. Additionally, the antioxidant properties of all the compounds were measured using the DPPH and ORAC methods, and their metal-chelator effects were analysed using UV spectroscopy.

Result and Discussion: The cholinesterase inhibitory effects of all title compounds were evaluated, and compounds 2c, 2f, and 3b were determined to be selective butyrylcholinesterase (BChE) inhibitors. Specifically, the 4-fluorobenzylpiperazine derivative compound 2c (IC₅₀=8.96 μM) is the most potent selective BChE inhibitor in the series. In addition, all final compounds exhibit antioxidant properties according to the ORAC test. Also, all compounds chelate with different amounts of Cu(II), Fe(II), and Zn(II) ions.

Anahtar Kelimeler

• Alzheimer’s disease
• antioxidant
• cholinesterase inhibition
• metal chelator
• 4-methylthiazole

Destekleyen Kurum

Biruni University Scientific Project

Proje Numarası

BIRUNI-BAP-01-2023-01-31

Etik Beyan

The author declares that the ethics committee approval is not required for this study.

Teşekkür

This study was supported by the Biruni University Scientific Project [grant number BIRUNI-BAP-01-2023-01-31]. Prof. Dr. Deniz S. Doğruer is gratefully acknowledged for her support, encouragement, and expert advice throughout this research.

ALZHEİMER HASTALIĞININ TEDAVİSİ İÇİN YENİ ÇOK HEDEFLİ 4-METİLTİYAZOL TÜREVLERİNİN TASARIMI, SENTEZİ VE BİYOLOJİK AKTİVİTELERİNİN DEĞERLENDİRMESİ

Öz

Amaç: Bu çalışmada, sekiz yeni 4-metiltiyazol türevi bileşik Alzheimer hastalığının tedavisinde çoklu hedefe yönelik etki göstermesi hedeflenerek tasarlandı ve sentezlendi. Kolinesteraz inhibitör aktiviteleri, antioksidan özellikleri ve metal şelatör etkileri in vitro olarak test edildi.

Gereç ve Yöntem: Sonuç bileşikleri sentez edebilmek için 4-metiltiyazol-2-amin başlangıç maddesi olarak kullanıldı. Metot A’ya göre öncelikle başlangıç maddesi ve 3-kloropropiyonil klorürün tepkimesinden ara ürün 1 elde edilmiştir. Daha sonra ara ürün 1’in uygun amin türevleri ile yer değiştirme reaksiyonundan sonuç ürünlere (2a-f) ulaşılmıştır. Bu yöntem ile elde edilemeyen sonuç ürünler (3a-b) metot B’ye göre başlangıç maddesi ve uygun propanoik asit türevlerinin reaksiyonuyla hazırlanmıştır. Sentezlenen ve saflaştırılan sonuç bileşiklerin yapıları ¹H-NMR, ¹³C-NMR ve HRMS yöntemleriyle aydınlatılmıştır. Yapıları aydınlatılan bileşiklerin kolinesteraz inhibitor etkileri modifiye Ellman yöntemiyle belirlenmiştir. Ayrıca tüm bileşiklerin antioksidan özellikleri DPPH ve ORAC yöntemiyle, metal şelatör etkiler ise UV-spektroskopisi ile ölçülmüştür.

Sonuç ve Tartışma: Sentezlenen bileşiklerin kolinesteraz inhibitör etkileri değerlendirildiğinde bileşik 2c, 2f ve 3b’nin selektif butirilkolinesteraz (BChE) inhibitörü olduğu belirlenmiştir. Özellikle 4-florobenzilpiperazin türevi bileşik 2c (IC₅₀ = 8.96 μM) serinin en güçlü bir BChE inhibitörü olarak göze çarpmaktadır. Tüm sonuç bileşikler ORAC testine göre antioksidan özellik göstermektedir. Buna ek olarak tüm bileşikler test edilen metal iyonlarıyla değişen oranlarda şelasyon yapmaktadır.

Anahtar Kelimeler

• Alzheimer hastalığı
• antioksidan
• kolinesteraz inhibisyonu
• metal şelasyonu
• 4-metiltiyazol

Destekleyen Kurum

Biruni Üniversitesi Bilimsel Araştırma Projeleri

Proje Numarası

BIRUNI-BAP-01-2023-01-31

Etik Beyan

Yazarlar bu çalışma için etik kurul onayının zorunlu olmadığını beyan etmektedir.

Teşekkür

Bu çalışma Biruni Üniversitesi Bilimsel Araştırma Projeleri tarafından (Proje no: BIRUNI-BAP-01-2023-01-31) desteklenmiştir. Yazar Prof. Dr. Deniz S. Doğruer'e çalışma boyunca yaptığı tüm katkılar için içtenlikle teşekkür etmektedir.

Kaynakça

1. 1. Alzheimer’s Association. (2025) 2025 Alzheimer’s disease facts and figures. Alzheimers Dement, 21(5). [CrossRef]
2. 2. Hampel, H., Mesulam, M.M., Cuello, A.C., et al. (2018). The cholinergic system in the pathophysiology and treatment of Alzheimer’s disease. Brain, 141(7), 1917-1933. [CrossRef]
3. 3. Cho, H.-J., Sharma, A.K., Zhang, Y., et al. (2020). A multifunctional chemical agent as an attenuator of amyloid burden and neuroinflammation in Alzheimer’s disease. ACS Chemical Neuroscience, 11(10), 1471-1481. [CrossRef]
4. 4. Scheltens, P., De Strooper, B., Kivipelto, M., et al. (2021). Alzheimer’s disease. The Lancet, 397(10284), 1577-1590.
5. 5. Dorababu, A. (2022). Promising heterocycle-based scaffolds in recent (2019-2021) anti-Alzheimer’s drug design and discovery. European Journal of Pharmacology, 920 (174847). [CrossRef]
6. 6. Luo, K., Chen, J., Li, H., et al. (2023). Design, synthesis and biological evaluation of new multi-target scutellarein hybrids for treatment of Alzheimer’s disease. Bioorganic Chemistry, 138(106596). [CrossRef]
7. 7. Li, Q., Xiong, B., Wang, Y., et al. (2022). A highly effective and stable butyrylcholinesterase inhibitor with multi-faceted neuroprotection and cognition improvement. European Journal of Medicinal Chemistry, 239(114510). [CrossRef]
8. 8. Li, Q., Yang, H., Chen, Y., et al. (2017). Recent progress in the identification of selective butyrylcholinesterase inhibitors for Alzheimer’s disease. European Journal of Medicinal Chemistry, 132(294-309). [CrossRef]

9. 9. Lu, X., Qin, N., Liu, Y., et al. (2022). Design, synthesis, and biological evaluation of aromatic tertiary amine derivatives as selective butyrylcholinesterase inhibitors for the treatment of Alzheimer's disease. European Journal of Medicinal Chemistry, 243(114729). [CrossRef]
10. 10. Wang, Y., Xiong, B., Lin, H., et al. (2022). Design, synthesis and evaluation of fused hybrids with acetylcholinesterase inhibiting and Nrf2 activating functions for Alzheimer's disease. European Journal of Medicinal Chemistry, 244(114806). [CrossRef]
11. 11. Rossi, M., Freschi, M., de Camargo Nascente, L., et al. (2021). Sustainable drug discovery of multi-target-directed ligands for Alzheimer’s disease. Journal of Medicinal Chemistry, 64(8), 4972-4990. [CrossRef]
12. 12. Zhang, P., Xu, S., Zhu, Z., et al. (2019). Multi-target design strategies for the improved treatment of Alzheimer's disease. European Journal of Medicinal Chemistry, 176, 228-247. [CrossRef]
13. 13. Bardakkaya, M., Kilic, B., Sagkan, R.I., et al. (2023). Synthesis and evaluation of multitarget new 2-aminothiazole derivatives as potential anti-Alzheimer's agents. Archiv der Pharmazie, 356(8), 2300054. [CrossRef]
14. 14. Kilic, B., Bardakkaya, M., Ilıkcı Sagkan, R., et al. (2023). New thiourea and benzamide derivatives of 2-aminothiazole as multi-target agents against Alzheimer's disease: Design, synthesis, and biological evaluation. Bioorganic Chemistry, 131(106322). [CrossRef]
15. 15. Dawood, D.H., Anwar, M.M. (2025). Recent advances in the therapeutic insights of thiazole scaffolds as acetylcholinesterase inhibitors. European Journal of Medicinal Chemistry, 287(117331). [CrossRef]
16. 16. Shakila, S., Kilic, B., Bardakkaya, M., et al. (2024). Multifunctional anti-Alzheimer's agents: Synthesis, biological evaluation, and molecular docking study of new 2-phenoxyacetamide/3-phenoxypropanamide/4-oxobutanamide derivatives. Journal of Molecular Structure, 1317(139106). [CrossRef]
17. 17. Mishra, C.B., Kumari, S., Tiwari, M. (2015). Thiazole: A promising heterocycle for the development of potent CNS active agents. European Journal of Medicinal Chemistry, 92, 1-34. [CrossRef]
18. 18. Erdogan, M., Kilic, B., Sagkan, R.I., et al. (2021). Design, synthesis and biological evaluation of new benzoxazolone/benzothiazolone derivatives as multi-target agents against Alzheimer’s disease. European Journal of Medicinal Chemistry, 212(113124). [CrossRef]
19. 19. Kılıç, B., Gülcan, H.O., Aksakal, F., et al. (2018). Design and synthesis of some new carboxamide and propanamide derivatives bearing phenylpyridazine as a core ring and the investigation of their inhibitory potential on in-vitro acetylcholinesterase and butyrylcholinesterase. Bioorganic Chemistry, 79, 235-249. [CrossRef]
20. 20. Kılıç, B., Erdoğan, M., Gülcan, H.O., et al. (2019). Design, synthesis and investigation of new diphenyl substituted pyridazinone derivatives as both cholinesterase and Aβ-aggregation inhibitors. Medicinal Chemistry, 15(1), 59-76. [CrossRef]
21. 21. Jehangir, U., Khan, S., Hussain, R., et al. (2024). In vitro and in silico correlation of bis-thiazole based Schiff base hybrids analogues: A computational approach develop to promising acetylcholinesterase and butyrylcholinesterase inhibitors. Journal of Molecular Structure, 1303(137585). [CrossRef]
22. 22. Bardakkaya, M., Kılıç, B., Doğruer, D. (2024). Bazı benzoksazol-2(3H)-on/benzotiyazol-2(3H)-on türevlerinin sentezi ve alzheimer hastalığına karşı etkilerinin incelenmesi. Journal of Faculty of Pharmacy of Ankara University, 48(1), 226-241. [CrossRef]
23. 23. Mahmood, M., Hussain, Z., Ullah, M.Z., et al. (2024). Evaluation of 3,4-diethoxy substituted thioureas and their thiazole derivatives as potent anti-Alzheimer's agents: Synthesis, DFT, biological activity and molecular modeling investigations. Journal of Molecular Structure, 1314, (138760). [CrossRef]
24. 24. Shidore, M., Machhi, J., Shingala, K., et al. (2016). Benzylpiperidine-linked diarylthiazoles as potential anti-alzheimer’s agents: Synthesis and biological evaluation. Journal of Medicinal Chemistry, 59(12), 5823-5846. [CrossRef]
25. 25. Kılıç, B. (2017). PhD Thesis. Bazı piridazin türevlerinin sentezi, asetilkolinesteraz ve butirilkolinesteraz inhibitör etkilerinin in vitro olarak incelenmesi. Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Gazi University, Ankara, Türkiye.