Comprehensive resources for ligand-based drug discovery

Natural products or plant extracts are the major sources of medicine; according to WHO, over 80% of the population directly depends on natural product-based medicine. Natural product-based medicine lacks a mechanism of action and information about the target involved in causing disease. Without a three-dimensional target protein structure, the drug discovery process becomes complex with limited tools and databases for natural products compared to structure-based drug discovery. In this instance, structural features and available knowledge of small molecules are used for ligand-based drug design and lead optimization. 3D Quantitative Structure-Activity relationship and Pharmacophore modeling are popular methods for ligand-based drug design also, reverse docking and target fishing are the widespread approaches for ligand-based target identification. This chapter comprehends available natural product and plant extract compound databases, web-based and system-based tools for 3D QSAR, pharmacophore modeling, target fishing, and reverse docking. Also, it covers the advantages and limitations of each tool.