Synthesis of some New Spiro 1,3,4-Oxadiazolines Derived from Azlactone

In this work a mixture of hippuric acid (N-benzoyl glycine) (1) and substituted benzaldehyde undergone Erlenmeyer and Perkin reactions respectively to afford the 4-aryl methylidene-2-phenyl oxazole-5-one (2a-d). This reaction proceeded under acidic media using acetic anhydride and sodium acetate. The azlactones (2a-d) used as starting material to prepare the imidazolone derivatives. New 4-aryl methylidene-5-oxo-2-phenyl-N'-(substituted cyclohexylidene)-4,5-dihydro imidazole-1-carbohydrazide(3a-j) were prepared from reactions the azlactones (2a-d) with Schiffs bases which prepared through condensation reaction of semicarbazide with substituted cyclo hexanone. Finally, the preparation of new 1-(4-acetyl-5-spiro substituted cyclohexyl-1,3,4-oxadiazol-2-yl)-4-aryl methylidene-2-phenyl-1H-imidazol-5-one (4a-j) via intracyclization reaction of imidazolones (3a-j) in the presence of acetic anhydride as suitable cyclizing agent. The structure of the synthesized compounds were illustrated by the available physical and spectral analysis (M.P, T.L.C, U.V, FT-IR and some of them by 1H-NMR) .