The book entitled "Synthetic Studies Towards Bioactive Organic Molecules" and it is divided into three chapters. Chapter one deals with the introduction and synthesis of Tamiflu by using Ramberg-Backlund reaction as key chemical transformation. The second chapter deals with introduction of aziridine chemistry and its application for the synthesis of Tamiflu by using ring closing metathesis (RCM) as key organic reaction. Chapter three deals with introduction and synthesis studies towards biotin.