1Hand13C NMR assignments of anticonvulsant 4 [3H] -Quinazolinones

A number of 3-[4'-carbamoylphenyl] 2-methyl-4[3H]-quinazolinones were prepared as potential anticonvulsants. Their 1H-and 13CNMR parameters were measured. Assignments of the different proton and carbon signals were made depending on the basis of the chemical shift theory, signal multiplicity, additivity rules and comparison with the data reported for analogous compounds, in addition to CH-COSY and DEPT experiments. By alteration of the substituents on the amide nitrogen, the spin system of the aromatic protons of the 3-[4'-carbamoy1pheny1] moiety could be changed from two doublets of AA' XX' type to a pair doublets of AA'BB' type and finally to a singlet