Catalysis of nifuroxazide formation by crosslinked poly(vinylpyridine)-supported acids

The condensation reaction of either 5-nitrofuran-2-aldehyde (NFA) or 5-nitr ofuran-2-aldehyde diacetate (NFAD) with p-hydroxybenzalhydrazide (PHBH) gav e nifuroxazide (NF), a drug used for the treatment of acute bacterial diarr hea, by catalysis with crosslinked poly(vinylpyridine)-supported acids (PVP HX). The product NF was obtained with high yield and purity. The effects of the counteranion, X-, in polymer catalyst (PVPHX) on the rate of the react ion were studied. It was found that the catalytic activity is increasing in order: I- > ClO4-, Cl- = Br- > TsO-. The effects of temperature and amount of catalyst on the reaction rate were discussed. (C) 1999 Published by Els evier Science B.V. All rights reserved.