Mass spectra of 1-Acyl-5-Aryl-Biurets

The EI mass spectra of the new 14 1-acyl-5-aryl-biurets were reported. Their mass spectral fragmentations were proposed on the basis of high resolution mass spectrometry and B/E linked scan spectra. The results show that the molecular ion is relatively strong, and the characteristic peak ArNCO~+ is a base peak.