Chemistry of 5-oxodihydroisoxazoles. Part 17.1 Acylation of 5-oxodihydroisoxazoles
作者:Rolf H. Prager、Jason A. Smith、Ben Weber、Craig M. Williams
DOI:10.1039/a700133i
日期:——
2-Unsubstituted isoxazol-5(4H)-ones and
-5(2H)-ones may be acylated by acid chlorides,
anhydrides or carboxylic acids in the presence of carbodiimides, to give
O- and N-acylated products. The solvent, the presence
of base and the temperature are found to alter the product ratios
dramatically, but the substituents present at C-3 have the greatest
effect. Aliphatic acid anhydrides and chlorides generally react at
nitrogen, but aroyl halides give significant proportions of
O-acylated products. Limited success in converting
O-aroyl to N-aroyl isoxazolones is reported.
作者:Francesco De Sarlo、Giuliano Dini、Pasquale Lacrimini
DOI:10.1039/j39710000086
日期:——
The reaction paths leading from ethyl propiolate to isoxazolin-5-one (II) and isoxazolin-3-one (III) are discussed and shown to be pH-dependent. The chemical and tautomericproperties of compound (II) are consistent with the known behaviour of its derivatives. The apparent dissociation constants of (II) and of its derivatives are analysed in terms of contributions from the tautomers present in aqueous
A novel isoxazole derivative, O-(5-isoxazolyl)-L-serine (OIS, 1), was synthesized by a Mitsunobu reaction of isoxazolin-5-one (4) with N-Boc-L-serine tert-butyl ester (5) and subsequent deprotection of the coupling product. Its structure was elucidated by spectroscopic analyses. The pharmacological activity of 1 was also examined with cloned glutamate receptors and transporters using a Xenopus oocyte-expressing