QSAR Studies of Nitric Oxide Synthase Inhibitors

Background:: Nitric oxide is a free radical bioregulator controlling homeostasis, vasodilation, and inhibition of platelet aggregation, significantly implicated in the nervous and immune system functionality. In vivo it is produced by nitric oxide synthases (NOSs). Objective:: Overproduction of nitric oxide is linked to several inflammatory, immunological, and neurodegenerative diseases and for that, various compounds have been synthesized as inhibitors of NOSs. In this review, the QSAR analyses were summarized in a variety of compounds as potent inhibitors of NOSs, and the models derived through 1D, 2D and 3D QSAR analyses. Conclusion:: Ten groups of various NOS inhibitors and 17 1D, 2D, and 3D QSAR models and analyses were presented and discussed. A lack of hydrophobic terms was noticed in most of the cases. Chemical substituents were selected considering the increase either of the hydrophilicity and/or of hydrophobicity, bulkiness supported steric interactions, and point to potent inhibitors. CMR (Calculated Molar Refractivity) a steric variable, with a negative sign, underlines the critical effects participating on (in) an active site on the enzymes. Indicator variables imply the influence of specific structural moieties. Electronic parameters were found to be significant.