Small bioactive molecules are pre-requisite for any discovery discipline. Being aware of the fact that bioactivity is not randomly dispersed in the vast chemical space, chemists have been developing hypothesis that can provide access to these islands of bioactivities. Natural products have always been a source of inspiration and their structural motifs provide biologically relevant starting points for library synthesis. In addition to that, Diversity Oriented Synthesis (DOS) and Biology Oriented Synthesis (BIOS) have emerged other tools to guide synthesis design and help enrich compound collections in biological activities. Coherent developments in chem- and bioinformatic tools and in organic synthesis methods targeting efficient synthesis of compound collections are required to identify interesting molecules that can be employed as probes in chemical biology research and as drug candidates in medicinal chemistry investigations.
Keywords: Natural products, diversity oriented synthesis, biology oriented synthesis, compound libraries, small molecules, drug discovery, bioactivity, protein inhibitor, cyclopeptides, chemical space