QSAR studies on <i>cis</i>-hexa and tetra-hydrophthalazinones: A new class of selective PDE-4 inhibitors

Abstract

Quantitative structure activity relationship studies have been carried out on <i>cis</i>-hexa and tetra-hydrophthalazinones, a new class of selective PDE-4 inhibitors. The 78 compounds analyzed were divided into a training set of 62 and test set of 15 molecules (excluding one compound) each describing a similar range of biological activity. Among several 2D and 3D

parameters. the molar refractivity, dielectric energy and structural parameters as indicator variables (I₁, I₂, I₃) best describe the variation in PDE-4 inhibitory activity in the training set with high correlation(<i>r</i>=>0.9) of >99% significance. These equations also show a good test set prediction (<i>r></i>0.8)<i> </i>and thus may be useful in designing new potential PDE4 inhibitors.