Functionalized Isoxazoles to Augment Your Building Block Collection

Isoxazole derivatives are now of great interest in many fields of research and technology [1-2]. From the organic synthesis standpoint, these compounds are versatile synthetic building blocks owing to their dormant functionalities, e.g., as enaminones, [3] 1,3-dicarbonyl compounds, and γ-amino alcohols [4]. The substituted isoxazole unit is present in several natural products, synthetic drugs, and other biologically active compounds [5]. For example, ibotenic acid 1 (Fig. 1) and the product of its decarboxylation have been isolated from several fungal species and are active central nervous system (CNS) agents [6]. Up to the present 13 isoxazole-containing drugs possessing a wide spectrum of biological activities have been successfully marketed [7]. Among them are antirheumatic drug Leflunomide 2 and antipsychotic agent Paliperidone 3 (both shown in Fig. 1), to name but a few. Furthermore, many isoxazole derivatives exhibit properties attractive for their technological applications, e.g., fluorescent sensors, [8] ligands for asymmetric synthesis, [9] and liquid crystals [10].

Figure 1. Natural compounds and synthetic drugs containing the isoxazole fragment.

Representatives of the isoxazole-containing compounds available from Life Chemicals are listed below. The full list of the functionalized isoxazoles can be obtained upon request by emailing marketing@lifechemicals.com.

References

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2. Giomi, D.; Cordero, F.M.; Machetti, F. in Comprehensive Heterocyclic Chemistry, 3rd edition, eds. A.R. Katritzky, C.A. Ramsden, E.F.V. Scriven, and R. J.K. Taylor Pergamon, Oxford, 2008. Vol. 4, p. 365.
3. Calle, M.; Calvo, L.A.; Gonzáles-Ortega, A.; Gonzáles-Nogal, A.M. Tetrahedron 2006, 62, 611.
4. Aschwanden, P.; Kværno, L.; Geisser, R.W.; Kleinbeck, F.; Carreira, E.M. Org. Lett. 2005, 7, 5741.
5. (а) Chikkula, K. V.; Raja, S. Int. J. Pharm. Pharmaceut. Sci. 2017, 9, 13-24. (b) Zhu, J.; Mo, J.; Lin, H.; Chen, Y.; Sun, H. Bioorg. Med. Chem. 2018, 26, 3065-3075.
6. Liu, J.-K. Chem. Rev. 2005, 105, 2723.
7. www.drugbank.ca; accessed in July 2019.
8. Yang, R.-H.; Chan, W.-H.; Lee, A.W.M.; Xia, P.-F.; Zhang, H.-K.; Li, K. J. Am. Chem. Soc. 2003, 125, 2884.
9. Arai, M.A.; Kuraishi, M.; Arai, T.; H. Sasai, H. J. Am. Chem. Soc. 2001, 123, 2907.
10. Haino, T.; Tanaka, M.; Ideta, K.; Kubo, K.; Mori, A.; Fukazawa, Y. Tetrahedron Lett. 2004, 45, 2277.