QSPR/QSAR in N-[(dimethylamine)methyl] benzamides substituents groups influence upon electronic distribution and local anesthetics activity

It was determined, with a systematic mode, the carbonyl group frequency in the region of the infrared of N-(dimethylamine)methyl] benzamides 4-substituted (set A) and their hydrochlorides (set B), that had its local anesthetical activity evaluated. The application of the Hammett equation considering the values of the absorption frequency of carbonyl group, nu(C=O,) using the electronic constants sigma, sigma(I), sigma(R), I and R leads to meaningful correlation. The nature and the contribution of substituent group electronic effects on the polarity of the carbonyl group was also analyzed. The use of the nu(C=O) as an experimental electronic parameter for QSPR studies was validated.