S. N. Shurov

Synthesis and structure of N-substituted 2-amino-3-phenacylidene-3,4-dihydroquinoxalines

N-Substituted 2-imino-5-aryl-2,3-dihydro-3-furanones react with o-phenylenediamine to form N-substituted 2-amino-3-phenacylidene-3,4-dihydroquinoxalines.

Character of Enolization of the β-Dicarbonyl Fragment in α , γ-Dioxocarboxylic Acids. Crystal and Molecular Structure of Benzoyl- and Cinnamoylpyruvic Acids

Benzoyl- and cinnamoylpyruvic acids have been investigated by X-ray diffraction. In crystals these acids exist as 2-hydroxy-4-oxo-4-phenyl-3(Z)-butenic and 4-hydroxy-2-oxo-6-phenyl-3(Z),5(E)-hexadienic acids, respectively, stabilized by intramolecular hydrogen bonding.

Reaction of 5-aryl-2,3-dihydrofuran-2,3-diones with ketene acetals

It is known that ketene acetals react with N-substituted isatins to give [2 + 2]-cycloadducts involving the ketone carbonyl group [1]. Other five-membered 2,3-dioxo heterocycles have not been previously investigated in this sort of reaction. We have established that 5-aryl-2,3-dihydrofuran-2,3-diones Ia, b react with ketene diethylacetal (IIa) and ketene di-n-butylacetal (IIb) to give alkyl 5-aryl-2-hydroxy-3-oxo-2,3-dihydrofuran-2-ylethanoates IIIa, b.