A quantum-chemical study of the relationships between electronic structure and the inhibition of cytophatic effects produced by the influenza A/Guangdong Luohu/219/2006 (H1N1) strain in MDCK cells by substituted acylamidobenzamides was carried out. The electronic structure of all the molecules was calculated within the Density Functional Theory at the B3LYP/6-31g(d,p) level with full geometry optimization. The cytotoxic activity of these molecules on this cell line was also analyzed. Despite the almost total lack of information regarding the mechanisms of antiviral action and cytotoxicity, we obtained statistically significant relationships between electronic structure and antiviral and cytotoxic activities. The variation of the antiviral activity is mainly orbitalcontrolled. The variation of cytotoxicity is charge- and orbital-controlled. The common skeleton used for his study seems to be correct. A short analysis of the MO-MO interaction is done. We suggest that the local atomic density of states, occupied and vacant, can be used as an approximate measure of the MO-MO penetration for the analysis of π-π stacking interactions.
