Several small heterocyclic molecules are very important in organic and medicinal chemistry. Their synthetic strategies are significant in drug discovery. And most of them are major constituent of several natural compounds such as alkaloids, histamine, histidine, biotin, nucleic acid etc. Many heterocyclic derivatives are being developed for different therapeutic actions. Interestingly they exhibited biological activities such as antimicrobial, anticancer, analgesic, anti-inflammatory, antiviral, anthelmintic, anticoagulant, anti-ulcer, anti-allergic activity etc. Therefore, this book firstly in three chapters aims to review some important small heterocyclic molecules (Flouroquinoline, Cumarines, Oxzasolidenones, Imidazole) its chemistry, synthesis and pharmacological activities. The subject of this book becomes a significant publication for anyone interested in synthesis and biomedical applications of heterocyclic small molecules. It provides a permanent written record deals withthe synthetic approach along with their applications in medicinal chemistry.