SYNTHESIS AND MODIFICATION OF ETHYL 2-(2-(-7H-IMIDAZO(2,1-b)(1,3)THIAZIN-5-YL)PHENOXY)ACETATE FOR AMYLOID AGGREGATION INHIBITION

Fausta Kairytė1, Indrė Misiūnaitė-Vaškevičienė1, Ieva Žutautė1

1 Institute of Chemistry, Faculty of Chemistry and Geosciences, Vilnius University, Vilnius, Lithuania

[email protected]

Amyloid fibril formation is a hallmark of numerous neurodegenerative and systemic diseases, including Alzheimer’s disease, Parkinson’s disease, and type II diabetes. The aggregation of misfolded proteins into amyloid plaques has been identified as a key pathological process contributing to cellular dysfunction and toxicity[1]. The urgency of identifying effective inhibitors of amyloid aggregation has led to extensive research into small-molecule modulators capable of disrupting fibril formation or stabilizing non-toxic conformations of amyloidogenic proteins[2]. Among these small molecules, imidazole-based compounds have emerged as promising candidates due to their unique electronic properties and ability to interact with protein aggregation pathways[3]. The imidazo[2,1-b][1,3]thiazine scaffold, in particular, has garnered interest for its bioactive potential, as derivatives of this core structure have demonstrated anti-amyloidogenic properties[4].

Following previous research, ethyl 2-(2-(7H-imidazo[2,1-b][1,3]thiazin-5-yl)phenoxy)acetate was chosen for functional group position evaluation in the core structure of 5-arylimidazo[2,1-b][1,3]thiazine. The desired compound was synthesized with a cyclization reaction of appropriate 2-alkynylthioimidazole. Further modification of the ester group led to a purposive group of compounds required for further structural-activity relationship investigation on inhibition of alpha-synuclein aggregation.

Figure 1
Fig. 1. Ethyl 2-(2-(7H-imidazo[2,1-b][1,3]thiazin-5-yl)phenoxy)acetate synthesis and its further modification.


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[2] Fabrizio Chiti, Christopher M. Dobson, “Protein Misfolding, Amyloid Formation and Human Disease: a Summary of Progress Over the Last Decade,” Ann. Rev. Biochem., 2017, 86, 28-38.

[3] X. Zhang, J. Liu, L. Huang, X. Yang, R. B. Petersen, Y. Sun, H. Gong, L. Zheng., K. Huan, “How the imidazole ring modulates amyloid formation of islet amyloid polypeptide: A chemical modification study,” Prog. Biophys. Mol. Biol., 2016, 124, 1-9.

[4] I. Misiūnaitė, K. Mikalauskaitė, M. Paulauskaitė, R. Sniečkutė, V. Smirnovas, A. Brukštus, M. Žiaunys, I. Žutautė, “Imidazo[2,1-b][1,3]thiazine Derivatives as Potential Modulators of Alpha-Synuclein Amyloid Aggregation,” ACS Chem., Neurosci., 2024, 24, 4418-4430.