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,  1,3-dicarbonyl compounds, and γ-amino alcohols . The substituted isoxazole unit is present in several natural products, synthetic drugs, and other biologically active compounds . 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 . Up to the present 13 isoxazole-containing drugs possessing a wide spectrum of biological activities have been successfully marketed . 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,  ligands for asymmetric synthesis,  and liquid crystals .
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 firstname.lastname@example.org.
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