Reactions of 5(4H)-oxazolones with Wittig-Horner reagents: Novel synthesis of dioxopyrrolidinephosphonates and phosphonoalkanoates with anticipated schistosomicidal activity

Abstract

4-Benzylidene-2-phenyl-5(4H)-oxazolones react with Wittig-Horner reagents in the presence of alcoholic sodium alkoxide to give novel dioxopyrrolidinephosphonates, diethyl [3-(benzoylamino)-1-cyano-2-oxo-4- phenylbut-3-en-1-yl]phosphonate and phosphonoalkenoate derivatives. Both the phosphonate adducts and the ester products were also isolated from the reaction of oxazolones with triethyl phosphonoacetate using alcoholic sodium ethoxide and/or sodium hydride as a base. Possible reaction mechanisms are considered, and the structural assignments are based on analytical and spectroscopic results. The biological evaluation of the new compounds is reported. © 2008 Verlag der Zeitschrift für Naturforschung, Tübingen.