Ketonic oxidation products of cyclobarbital.

Chemical or biochemical oxidation of cyclobarbital yielded 5-(3-oxo-1-cyclohexen-l-yl)-5-ethyl -2,4,6- (lH,3H,5H)-pyrimidine-trione, and photochemical oxidation gave 5-(6-oxo-l-cyclohexen-l-yl)-5- ethyl-2,4,6-(lH,3H,5H)-pyrimidinetrione. These compounds were isolated and purified by TLC, and their structures were determined by UV, IR, NMR, and mass spectral data; the crystalline structure was determined by X-ray diffraction.