Comparative QSAR studies with molecular negentropy, molecular connectivity, STIMS and TAU indices: Part I - Tadpole Narcosis of di verse functional acyclic compounds
Kunal Roy, Dipak Kumar Pal, A. U. DE, Chandana Sengupta · Indian Journal of Chemistry Section B-organic Chemistry Including Medicinal Chemistry · 1999
Comparative Quantitative Structure Activity Relationship (QSAR) studies on three different data sets of tadpole narcosis activity with molecular negentropy (I), molecular connectivity (IXV), STIMS (NI, NY and Nx) and TAU (T, TR, F, B) indices show that all of these are correlated to the activity nearly to the same extent and explain ',he variance of the datasets better than the atopological parameter,vertex count (N,,), though only TAU and STIMS indices have diagnostic features. Stepwise linear regression analyses reveal the importance of shape (B or NX & NY) and size ( Nv or NI ) parameters . as the mechanistic interpreters of the activity . Further, significant contribution of functionality index (F) in re gre ss ion an alyses with two datasets provides a scope for re-evaluation of the nonspecific nature of tadpole narcosis. Variations in molecular structures in a series lead to changes in physicochemical properties and biological activities in a quantitative wayl and thus information encoded within molecular structures may be correla ted with various properties (including biological activities) of the compounds. Viewed differently, physicochemical properties and biological activities may be interpreted as functions of structural information of the molecules 1-3. One of the tasks of organic chemists is to develop suitable indices that may reveal the features encoded within the structures and impart predictability for new or unknown compounds, the ultimate goal of QSAR and QSPR studies.