Abstract The tests have shown that the synthesized salts [1] 3-(N-1-naphthylcarboxamido)-N-benzylpyridinium chloride, 3-(N-2-naphthylcarboxamido)-N-benzylpyridinium chloride, 3-(N-2-naphthylcarboxamido)-N-allylpyridinium bromide and 3-(N-(3-quinolyl-N-benzylquinolilium chloride carboxamido)pyridyl-N-benzylpyridinium chloride exhibit significant anti-corrosion activity compared to the industrial inhibitor KI-1. 3-(N-phenylcarboxamido)-N-benzylpyridinium chloride, 3-(N-1-naphthylcarboxamido)-N-benzylpyridinium chloride and 3-(N-2-naphthylcarboxamido)-N-benzylpyridinium chloride were investigated for antibacterial and fungicidal activity. The Firefly software package was used to calculate the most energetically favorable conformations for the compounds 3-(N-phenylcarboxamido)-N-benzylpyridinium chloride, 3-(N-1-naphthylcarboxamido)-N-benzylpyridinium chloride, 3-(N-2-naphthylcarboxamido)-N-benzylpyridinium chloride, and 3-(N-(2-pyridyl)carboxamido)pyridyl-N,N-dibenzylpyridinium chloride, 3-(N-(4-pyridyl)carboxamido)pyridyl-N,N-dibenzylpyridinium chloride, and 3-(N-(3-quinolyl-N-benzylquinolilium chloride)carboxamido)pyridyl-N-benzylpyridinium chloride. It is shown that compounds with the highest anti-corrosion ability have a more planar fragment, as a result of which the protected metal surface increases. For these same compounds, the calculation of the energies of the VZMO and HVMO, as well as their dipole moments, was carried out. A correlation was established between the corrosion inhibition coefficient γ and the energy difference ΔE and their derivative ΔN (the fraction of electrons transferred). An exponential form of these correlations was proposed.