Hydrogen bonds and antiviral activity of benzaldehyde derivatives

We have obtained the Fourier transform IR spectra of solutions of benzaldehyde derivatives having different antiviral activities against a herpes virus. We observe a correlation between the presence of hydrogen bonds in the benzaldehyde molecules and the appearance of antiviral properties in the compounds. For compounds having antiviral activity, we have obtained spectral data suggesting the existence of hydrogen bonds of the type C=O⋅⋅⋅H–O and O–H⋅⋅⋅O in the molecules. When the hydrogen atom in the hydroxyl groups are replaced by a methyl group, no intramolecular hydrogen bonds are formed and the compounds lose their antiviral activity.