Use of distance geometry approach for the in vitro antiviral activity evaluation of N-bridgehead C-nucleosides

We have used a 3-dimensional receptor model of parainfluenza virus type 3 developed by Ghose et al using the distance geometry approach to analyze the in vitro antiviral activity of several novel ribonucleosides from imidazotriazine, imidazo-pyrazine and triazolo-pyrazine and pyridine series. On the basis of atomic physicochemical properties ie hydrophobicity, molar refractivity and charge density the interaction energy of minimum energy conformations of 22 compounds with hypothetic virus active site were evaluated. Seven nucleosides from imidazo-pyrazine and imidazo-triazine series have shown significantly high calculated values of virus rating while the analogues with triazolopyrazine, triazolo-pyridine and pyrazolo-pyridine heterocycles are expected to have only slight or moderate virus activity