Synthesis of Isoxazolines and Isoxazoles Using Poly(ethylene glycol)
as Support

Abstract

A general method for the liquid-phase syntheses of isoxazoles and isoxazolines through a 1,3-dipolar cycloaddition is described. The poly(ethylene glycol) (PEG)-supported alkyne 2 or alkene 6 reacted with nitrile oxides generated in situ from aldoximes 3, followed by cleavage from the PEG, to give isoxazoles or isoxazolines in good yield and purity.

Key words

poly(ethylene glycol) - isoxazolines - isoxazoles - cycloaddition - liquid-phase

References

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9

A search in MDDR (MDL data base) revealed the presence of more than 250 structures based on the isoxazole scaffold and endowed with several pharmacological activities used for analgesia, inflammation, immunology and CNS diseases (such as anxiety, memory impairment, depression, Parkinson’s and stroke).